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docs(AGENTS): rewrite the root standing orders to the 1,500-word budget

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Applies the documentation standard to its biggest offender. Every rule
survives as one to three lines plus a link to its durable home; the
stories, duplicate statements, and re-narrations go:

- Situational clusters evict to new homes: docs/testing.md (tiers,
  with-key policy, real-over-mock, world-verification, real-entry-path
  guards), docs/defensive-patterns.md (the bug-class rules), and
  docs/cookbook/responding-to-pr-review-on-a-stack.md (the stacked-PR
  review procedure).
- Doc-authoring rules consolidate into docs/AGENTS.md § Writing rules
  (current-state-never-history, md-wrap, ts-block compilation, @mode,
  catalog same-change, pair same-change).
- packages/README.md drops to the group table + the extension-vs-bundle
  dependency rule; the hand ASCII graph yields to the generated
  module-graph.md; group READMEs are the canonical per-package map.
- packages/AGENTS.md keeps only its packages-specific rules (export
  shape, ctx.get, real-Loader coverage); examples/AGENTS.md repoints
  its with-key-policy link; rfc/README.md loses a narrated-history
  aside; dsh-code-review / dsh-find-simplifications / verify-md-wrap
  references follow the moved content.
- Budget manifest ratchets: AGENTS.md 8200 -> 1500 (now 1,495 words),
  packages/README.md 1900 -> 600, packages/AGENTS.md 600 -> 450; the
  two new eviction docs join the budget set (testing 800, defensive
  550); docs/AGENTS.md raises 1000 -> 1250 for the absorbed writing
  rules (the one justified increase). The doc-tiers RFC's deferred list
  prunes the two items this change ships.
This commit is contained in:
Tianyi Cui
2026-07-04 14:22:47 +08:00
parent aa36b3b36b
commit 7702a33531
16 changed files with 200 additions and 400 deletions
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12
.agents/skills/dsh-code-review/SKILL.md
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@@ -22,8 +22,8 @@ Independent judgment governs *what to look at* and *how to apply a rule to this
These define the conventions and gates this repo is checked against, and they are authoritative. Read them at the source so this skill never drifts out of sync — and apply judgment in *interpreting* them for the case at hand, not in deciding whether they apply.
- **[AGENTS.md](../../../AGENTS.md) § Conventions** — effect-based registrations, declaration-merging for events/ctx keys, waterfall `next()` discipline, discriminated-union match-don't-chain, explicit-over-implicit at seams, the empty-`catch` rule, symmetry.
- **AGENTS.md § Defensive patterns (hard-won)** — each bullet is a bug class that bit us. Reviewing anything touching process lifecycle, async/await, disposal, or adapter error paths? Re-read this first — then look for the *adjacent* mistake it doesn't name.
- **AGENTS.md § Type Safety and Documentation** — the doc-sync rule (code change ⇒ update README + JSDoc in the SAME commit) and the no-hard-wrap markdown convention.
- **[docs/defensive-patterns.md](../../../docs/defensive-patterns.md)** — each section is a bug class that bit us. Reviewing anything touching process lifecycle, async/await, disposal, or adapter error paths? Re-read this first — then look for the *adjacent* mistake it doesn't name.
- **AGENTS.md § Type safety and documentation + [docs/AGENTS.md](../../../docs/AGENTS.md)** — the doc-sync rule (code change ⇒ update README + JSDoc in the SAME commit) and the writing rules (current-state-never-history, one line per paragraph, one home per fact, the word-budget gate).
- **[packages/AGENTS.md](../../../packages/AGENTS.md)** — per-package conventions (file layout, the HMR-safety test requirement).
- **[docs/i18n/translation-rules.md](../../../docs/i18n/translation-rules.md) and [docs/i18n/terminology.md](../../../docs/i18n/terminology.md)** — the authoritative standard for bilingual-doc review: faithfulness, structure, typography, and the binding terminology table. For PRs touching translated docs or pending terms, read these before judging the translation; [dsh-translate-docs](../dsh-translate-docs/SKILL.md) is the translator workflow.
- **[RFC index](../../../docs/rfc/README.md)** — the *why* behind the architecture. Especially [quality gates](../../../docs/rfc/implemented/process/2026-06-11-quality-gates.md) (what a PR must pass) and [capability seams](../../../docs/rfc/implemented/architecture/2026-06-13-capability-seams.md) (the three-package split). If a change seems to fight an RFC, that's a discussion, not a silent override — and not an automatic veto either: an RFC can be wrong for this case, so reason about it.
@@ -35,19 +35,19 @@ These come straight from the source docs above. They are not discretionary; abse
1. **Docs in sync.** If the PR changes a config key, default, error code, wire field, or event name, it must update the package README + module/JSDoc in the same diff. The `doc-sync` gate (check #4) does not catch prose drift in config keys, defaults, error codes, or wire fields — that is on the reviewer, but it is still required, not optional.
2. **Core-data-structures catalog in sync.** If the PR adds, removes, or reshapes a type the [core-data-structures catalog](../../../docs/core-data-structures/core.md) documents — a new `…Map` variant, a new content-block/session-event type, a field on `GenerateOptions`/`Agent`/`ToolDefinition`/a bash type, or a whole new core/seam type — it must update that catalog in the same diff (prose + any verbatim ` ```ts type-equiv ` block + the 1:1 `scripts/type-equiv.manifest.json`). The `verify-type-equiv` gate (part of `doc-sync`) catches a *drifted paste* of an already-documented type, but it cannot tell you a brand-new core type went undocumented — that judgment is yours. Confirm a genuinely spine-level type landed in core.md and a new capability's vocabulary on a sub-page, per the spine-vs-seam line in [core.md § What counts as "core"](../../../docs/core-data-structures/core.md#what-counts-as-core). A pure internal type with no cross-package reach needs no catalog entry — say so if it's a judgment call.
3. **HMR-safety test.** Any new registry/registration needs a test that disposes the contributing fiber and asserts cleanup (packages/AGENTS.md). Its absence blocks merge.
4. **Quality gates pass.** typecheck, lint, test, test:coverage (100% per-file on `packages/*/src`), knip, build, publint, constraints, `doc-sync` (doc-typecheck + verify-cordis-catalog + verify-tool-catalog + verify-md-wrap + verify-md-links + verify-doc-refs + verify-package-paths + verify-rfc-classification + verify-type-equiv + verify-translation-pairing), module-graph freshness (the quality-gates RFC). Don't re-review what a gate already enforces — trust the gate and spend attention on what it can't check. Note that the `doc-sync` gate only covers compilable `ts` blocks, the generated cordis events/services catalog, markdown wrapping/links, verbatim type-equiv blocks, and the bilingual pairing contract ([docs/i18n/README.md](../../../docs/i18n/README.md)); prose drift (checks #1 and #2) and translation *quality* (the [dsh-translate-docs](../dsh-translate-docs/SKILL.md) rules) are *additional* manual review on top of it, not covered by it.
4. **Quality gates pass.** typecheck, lint, test, test:coverage (100% per-file on `packages/*/src`), knip, build, publint, constraints, `doc-sync` (the full gate list is the `doc-sync` script in the root `package.json`), module-graph freshness (the quality-gates RFC). Don't re-review what a gate already enforces — trust the gate and spend attention on what it can't check. Note that `doc-sync` only covers compilable `ts` blocks, generated-catalog freshness, markdown wrapping/links/refs, verbatim type-equiv blocks, word budgets, and the bilingual pairing contract ([docs/i18n/README.md](../../../docs/i18n/README.md)); prose drift (checks #1 and #2) and translation *quality* (the [dsh-translate-docs](../dsh-translate-docs/SKILL.md) rules) are *additional* manual review on top of it, not covered by it.
## Reviewer-only checks (gates can't catch these — judgment required)
Where your independent reasoning earns its keep. Start here, then keep going across the broader aspects above.
- **e2e verifies the world, not the agent's self-report.** For real-API tests, confirm the assertion re-runs the command/checks the file externally — a keyword probe lets a cheating agent pass (see AGENTS.md e2e bullet). For a behavior change to the agent's real flows, a no-key/mock test alone is usually insufficient: a with-key e2e (especially a smoke test that boots the real example and checks the world) is cheap here and catches "green units, broken product" — encourage it rather than treating real-API tests as expensive (see AGENTS.md § Secrets / .env).
- **e2e verifies the world, not the agent's self-report.** For real-API tests, confirm the assertion re-runs the command/checks the file externally — a keyword probe lets a cheating agent pass. For a behavior change to the agent's real flows, a no-key/mock test alone is usually insufficient: a with-key e2e (especially a smoke test that boots the real example and checks the world) is cheap here and catches "green units, broken product" — encourage it rather than treating real-API tests as expensive (see [docs/testing.md](../../../docs/testing.md)).
- **Plugin export shape + real-loader coverage.** A new/changed `cordis.yml`-loaded plugin: is it a function/namespace plugin (`name`/`inject`/`Config`/`apply` named exports) with NO `export default`? A stray default export makes the Loader's `unwrapExports` drop `inject` and the plugin crashes at load with `cannot get property … without inject` — invisible to hand-built `ctx.plugin({...})` tests and to line coverage. Confirm there's a test driving it through the REAL loader path (the no-key subprocess e2e for ACP is the model). And any opportunistic read of a service NOT in `static inject` should use `ctx.get(name)`, not `ctx.<name>` (the property proxy throws through a foreign shadow). See [packages/AGENTS.md](../../../packages/AGENTS.md) and [docs/postmortem/0001](../../../docs/postmortem/0001-acp-default-export-drops-inject.md).
- **Seam discipline.** New swappable capability? Check it's split per the capability-seams RFC (interface / impl / consumer), and that the consumer injects the interface key, never an implementation type.
- **Test quality — sufficiency, not just coverage.** 100% per-file coverage and a green suite are necessary, not sufficient: they prove the lines *ran*, not that the feature *works the way it ships*. Judge whether the tests are sufficient on two axes. (1) **Would they fail if the behavior regressed?** A test that passes but asserts the wrong thing — or restates the implementation instead of the contract (events fired, disposal reached, the world changed) — is worse than none. (2) **Do they exercise the REAL thing, the way it's actually used?** Prefer the genuine collaborator over a fake, drive the change through its real entry path (the cordis Loader, the ACP bridge, a booted subprocess — not a hand-built `ctx.plugin({...})` that bypasses `unwrapExports`), and verify the WORLD (re-read the file/log/registry externally), not the agent's self-report. A test that fakes the inputs just enough to cover every line will agree with whatever the author assumed; the real thing won't. When a test sets up a *clean/happy* path to reach a line, ask whether the line's PURPOSE is exercised — e.g. a durability/teardown path "tested" by a fully-completed turn never proves the mid-flight teardown it exists for; a torn-tail recovery branch covered by a well-formed log never proves recovery. Flag tests that hit the line but not the scenario. See AGENTS.md § Defensive patterns "Line coverage is not behavior coverage" and "Prefer the REAL implementation over a mock/stand-in in tests".
- **Test quality — sufficiency, not just coverage.** 100% per-file coverage and a green suite are necessary, not sufficient: they prove the lines *ran*, not that the feature *works the way it ships*. Judge whether the tests are sufficient on two axes. (1) **Would they fail if the behavior regressed?** A test that passes but asserts the wrong thing — or restates the implementation instead of the contract (events fired, disposal reached, the world changed) — is worse than none. (2) **Do they exercise the REAL thing, the way it's actually used?** Prefer the genuine collaborator over a fake, drive the change through its real entry path (the cordis Loader, the ACP bridge, a booted subprocess — not a hand-built `ctx.plugin({...})` that bypasses `unwrapExports`), and verify the WORLD (re-read the file/log/registry externally), not the agent's self-report. A test that fakes the inputs just enough to cover every line will agree with whatever the author assumed; the real thing won't. When a test sets up a *clean/happy* path to reach a line, ask whether the line's PURPOSE is exercised — e.g. a durability/teardown path "tested" by a fully-completed turn never proves the mid-flight teardown it exists for; a torn-tail recovery branch covered by a well-formed log never proves recovery. Flag tests that hit the line but not the scenario. See [docs/testing.md](../../../docs/testing.md) § "Test the real entry path" and § "Prefer the real implementation over a mock".
- **Snapshot coverage for transcript/UX changes.** If the PR changes the editor-facing transcript or end-to-end agent UX — the ACP bridge's event→update translation, the agent loop's observable output, tool presentation, or anything an editor renders — it must add or update a snapshot scenario (`examples/*/tests/**/*.snapshot.ts`, goldens under `examples/acp-agent/tests/snapshots/`) or note explicitly why none applies (AGENTS.md § Conventions). Review the golden diff itself: a changed `stdout.golden.txt` / `session.golden.txt` is a behavior change in disguise — confirm it's intended, not an accidental regression someone re-recorded away. A pure internal refactor with no observable-output change is exempt, but the PR should say so. See [docs/rfc/implemented/testing/2026-06-19-acp-snapshot-tests.md](../../../docs/rfc/implemented/testing/2026-06-19-acp-snapshot-tests.md).
- **Bilingual docs: review translation quality, not just pairing.** If the PR adds or edits a doc pair, read the changed English and Chinese sides and compare the meaning, not only the mechanical diff. Verify terms against [terminology.md](../../../docs/i18n/terminology.md), including first-occurrence annotations and "do not translate as" prohibitions; if a new term has no established precedent, the PR should keep it in English, list it under `待定术语`, and update the terminology table once the rendering is decided. A green `verify-translation-pairing` only proves hashes, switchers, and structure were recorded — it does not prove the translation is faithful, natural, or correctly termed. Treat [translation-rules.md](../../../docs/i18n/translation-rules.md) MUST/MUST NOT violations as blocking.
- **Intent and contracts.** Does the change do what the PR says, and honor the documented contract on *both* sides of every seam it touches (see AGENTS.md "Honor cross-seam contracts on BOTH sides")?
- **Intent and contracts.** Does the change do what the PR says, and honor the documented contract on *both* sides of every seam it touches (see [docs/defensive-patterns.md](../../../docs/defensive-patterns.md) "Honor cross-seam contracts on BOTH sides")?
## How to respond

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@@ -9,7 +9,7 @@ This skill helps turn a broad "find things to simplify" request into evidence-ba
## Start With Repo Context
- Read `AGENTS.md`, especially the pre-release stance, tests-document-behavior section, conventions, defensive patterns, and Type Safety and Documentation section.
- Read `AGENTS.md`, especially the pre-release stance and the conventions (including the tests-are-not-golden-truth and RFCs-are-not-golden-truth doctrines), plus [docs/defensive-patterns.md](../../../docs/defensive-patterns.md) and [docs/testing.md](../../../docs/testing.md).
- Skim [docs/architecture.md](../../../docs/architecture.md) before judging anything under `packages/`; simplifications that fight the service map or event taxonomy need extra evidence.
- Use the RFC index ([docs/rfc/README.md](../../../docs/rfc/README.md)) to understand intentional architecture. The most relevant implemented examples are [drop mutable session summary](../../../docs/rfc/implemented/simplification/2026-06-19-drop-mutable-session-summary.md), [shared persistence write coordinator](../../../docs/rfc/implemented/architecture/2026-06-18-shared-persistence-write-coordinator.md), [capability seams](../../../docs/rfc/implemented/architecture/2026-06-13-capability-seams.md), and the twin adapter / dual persistence backend RFCs.
- Treat dual LLM adapters and dual persistence backends as intentional by default. Do not propose deleting either twin/backend as "low effort" unless the user explicitly overrides that constraint. Removing an unused method or hook inside a protected seam can still be valid if it does not collapse the protected design.

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@@ -1,217 +1,58 @@
# AGENTS.md
This is the monorepo for the DeepSeek Harness group. It currently hosts the code for **DeepSeek Code**, DeepSeek's coding agent product.
This is the monorepo of the DeepSeek Harness group; it hosts **DeepSeek Code**, DeepSeek's coding agent product. The codebase is built on the vendored Cordis framework, microkernel-style: **everything is a plugin**. Read [docs/architecture.md](docs/architecture.md) before changing anything under `packages/` — the service map, event taxonomy, loop lifecycle, and extension seams. The documentation standard is [docs/AGENTS.md](docs/AGENTS.md). Design context: [Coding Harness MVP 需求分析](https://trtgsjkv6r.feishu.cn/wiki/ZwK6wfBE9i91V6kzMGYcgRGanxg), [微内核Harness实现思路](https://trtgsjkv6r.feishu.cn/wiki/VS9Lw1kQki6mDJk2UHocyuphnsc).
## Pre-release stance: foundation over blast radius
**This applies only while the harness is unreleased — remove this section at the first tagged/published release.** There are no external consumers yet, so optimize for the *correct foundation*, not for a small diff. When the right structure means moving a file across package boundaries, renaming a public symbol, or repackaging a plugin, do it — and update every reference in the same change. Do **not** add backward-compat shims, deprecation aliases, re-export stubs, or "keep it where it is to avoid churn" hedges; those are debts you take on to protect callers you do not have. Churn now is cheap; a wrong foundation set in stone is not. (Once released, this inverts — backward compatibility becomes a real constraint and this section comes out.)
**This applies only while the harness is unreleased — remove this section at the first tagged release.** There are no external consumers, so optimize for the correct foundation, not a small diff: move files, rename public symbols, repackage plugins, and update every reference in the same change. No backward-compat shims, deprecation aliases, or re-export stubs. On-disk formats need no migrations — a backend REJECTS anything not at the current version. Two sanctioned version stances: monotonic bump-and-reject (the SQLite backend's `SCHEMA_VERSION`), and a pinned `0` that absorbs all shape churn (`SESSION_FORMAT_VERSION` in `dsh-session`, documented "no compatibility implied") so the instability stays explicit. Real version policy begins at the first release.
This extends to **on-disk formats, schemas, and stored data**: while unreleased there is no persisted user data to preserve, so a format/schema/contract change needs **no migration path** — a backend REJECTS anything not at the current version rather than upgrading it. How the *version number itself* behaves pre-release is a per-format choice between two equally-valid stances, and the repo uses both deliberately. **Monotonic bump-and-reject**: each breaking change increments the version — e.g. the SQLite backend's `SCHEMA_VERSION` bump that drops columns rejects any non-current `user_version` on open, with no migration; use it when a stored artifact has a small enumerable set of revisions worth telling apart. **A pinned `0` "unstable / pre-release" version**: the format stays at `0` and absorbs ALL pre-release shape churn without bumping, while a backend still rejects any non-`0` log — the session event log uses this (`SESSION_FORMAT_VERSION = 0` in `dsh-session`), because its shape changes often while unreleased and bumping on every tweak would dress up an unstable format as a sequence of stable boundaries that mean nothing yet; pinning `0` and documenting it "no compatibility implied" makes the instability *explicit* instead of pretending each revision is a real version. Either way there is no migration code, and either way a real monotonic policy begins at the first tagged release. A migration written now is a shim for data that does not exist.
## Tests document behavior, not golden truth
A passing test pins the behavior the code **currently** has — not necessarily the behavior it **should** have. Existing tests faithfully document existing behavior, but existing behavior is not automatically golden: it can be the residue of a past compromise, a half-built feature, or a limitation that no longer applies. So when a refactor or review makes you ask "can I change this?", a green test is **not** the answer — the question is whether the behavior the test pins is actually correct.
Before you preserve a behavior solely to keep a test green, ask: is this behavior load-bearing (a real consumer depends on it, a contract promises it, a user observes it), or is it an artifact? If it's an artifact, **change the behavior AND its test together, in the same change, and say why in the PR** — do not contort new code to keep an obsolete assertion passing, and do not treat "but the test expects X" as a reason X must stay. Conversely, do not delete a test just because it is inconvenient: the discipline cuts both ways — you must show the *behavior* is dead, not merely that the test is in your way.
The worked example is [Drop the mutable session summary](docs/rfc/implemented/simplification/2026-06-19-drop-mutable-session-summary.md): an entire `SessionSummary` type, a `SessionPersistence.update()` method, a JSONL sidecar, and SQLite columns existed and were exercised by their own contract test — yet **nothing in production CONSUMED any of it, and `update()` had no production caller**. (The backends did *write* summary state — JSONL touched the sidecar after a durable append, SQLite bumped `updated_at` in the append transaction — but those writes fed only reads that nothing performed.) The tests documented the behavior perfectly; the behavior was dead. Deleting the behavior and its tests together removed ~400 lines and erased a durability divergence the next refactor would have had to model. (This is the test-tier echo of "verify the world, not a synthetic stand-in" in § Defensive patterns: a test agrees with whatever it was written to assert; only a real consumer proves the behavior matters.)
## RFCs are proposals, not golden truth
The same discipline applies one level up, to the RFCs in `docs/rfc/`. A **proposed** RFC records an *intended* change argued at a point in time; it is not a contract to implement verbatim. The author reasoned from the code as they understood it then — and they can be wrong, or the code can have moved. So before implementing an RFC, **validate its premise against the current code first**: confirm the thing it wants removed or changed is actually dead/safe, and that the migration it proposes is genuinely cleaner than what exists.
When carrying out the change fights back — a removal forces an awkward migration, deletes machinery that turns out to be load-bearing, or pushes consumers onto a more brittle hand-rolled equivalent — treat that friction as **evidence the RFC over-reached**, not as work to push through. Keep, split, or amend the change to match what the code actually wants, and say so in the PR. An RFC that ships in amended form gets its text amended on the way to `implemented/`, so the landed RFC describes what actually shipped rather than the original guess. The discipline cuts both ways: an RFC is also not a reason to *avoid* a change a maintainer would otherwise make — it is one input, weighed against the code in front of you.
The worked example is [Keep one public stop primitive](docs/rfc/implemented/simplification/2026-06-20-public-agent-stop-surface.md): it proposed removing BOTH `Agent.abort()` and `Agent.whenIdle()` as redundant stop/quiescence surface. Validating against the code, `abort()` was genuinely dead — no production caller, the loop aborts its own `AbortController` directly — so it was removed as proposed. But `whenIdle()` was load-bearing: a deliberate quiescence primitive with live ACP consumers, and the RFC's suggested migration (observe the `running`→`idle` transition by hand) is exactly the brittle path § Defensive patterns warns against ("Async state is not synchronous state"). So only `abort()` shipped, `whenIdle()` stayed, and the RFC's text was amended on the way to `implemented/` to record the narrowed scope — the landed RFC is not a lie about what was built.
## Orchestrating review feedback across a stacked PR chain
A wave of review comments lands across several PRs in a dependent stack (`A ← B ← C …`) at once. Resolving it well is a discipline of its own, learned the hard way:
- **One worktree per PR branch; never rewrite a pushed branch.** Each PR's fixes happen in that PR's own worktree. To bring a child up to date with a parent's new commits, **merge the parent down** — never rebase/amend/force-push a branch that is already pushed (see [§ Conventions](#conventions) "Never rewrite a pushed branch"). The stacked-merge graph and the per-round review-fix history depend on it.
- **A fix belongs on the PR that INTRODUCED the issue, then flows DOWN.** When a comment on PR `B` points at code `B` introduced, fix it on `B` and merge `B` into `C` — even if `C` already carries the same file through the chain. Originating the fix on the downstream `C` leaves `B` shipping the unfixed code and the fix invisible to a reviewer of `B`. (This bit us: a snapshot-test guard flagged on the lower PR got fixed only on the top PR, so the lower PR still read as unaddressed until the fix was relocated to its true origin and merged down.)
- **Each review fix is a SEPARATE commit, never an amend.** The "fix review findings" commit is part of the record — it shows what the review caught and how. Amending erases that. (Amend is fine only for your own not-yet-pushed work.)
- **Delegated work is trust-but-verify.** When sub-agents implement fixes in parallel, their report describes what they INTENDED, not necessarily what landed. Re-run the gates yourself on the actual tree, and for a regression guard, **prove it FAILS on the unfixed code** (introduce the regression, watch the test go red, revert) — a guard that passes both ways guards nothing. A sub-agent that "reframes the problem as already-handled" instead of fixing it is a signal to dig in personally, not to accept the reframing.
- **Triage on the merits, then reply in-thread.** Verify each comment against the code before acting (a reviewer flagging the right symptom can still mis-diagnose the cause — confirm both). Reply in the GitHub review thread (`gh api …/pulls/{pr}/comments/{id}/replies`), not as a top-level comment, stating the fix and the commit that carries it.
## Landing changes cleanly: gates and judgment
The recurring failure mode: a mechanical gate proves lines ran and types check; it never proves semantics, doc accuracy, or that a test guards anything. Layer the cheap human/AI judgment on top, in the right order, and keep each unit of work honestly scoped — and lean on an independent agent to review for the class of defect gates structurally cannot catch (prose/RFC/comment drift, a bug introduced while fixing, a test that asserts nothing load-bearing).
## Architecture
This codebase is based on the **Cordis** framework, built microkernel-style: **everything is a plugin**. All necessary Cordis dependencies are copied into this monorepo as vendored source (under `vendor/`) instead of being depended on via npm.
Read [docs/architecture.md](docs/architecture.md) before changing anything under `packages/` — it defines the service map, the event taxonomy, the session/turn/step lifecycle, and the plugin cookbook.
## Design Documents
- [Coding Harness MVP 需求分析](https://trtgsjkv6r.feishu.cn/wiki/ZwK6wfBE9i91V6kzMGYcgRGanxg) — requirement analysis for the initial MVP.
- [微内核Harness实现思路](https://trtgsjkv6r.feishu.cn/wiki/VS9Lw1kQki6mDJk2UHocyuphnsc) — discussion of the microkernel plugin-style architecture ("everything is a plugin").
## Repository Layout
## Repository layout
```
vendor/ Vendored Cordis framework source (original npm names, private).
See vendor/README.md for the manifest, local-modification log,
and the upstream sync procedure. Do NOT edit casually — every
divergence must be logged there.
packages/ Harness packages, grouped by role at packages/<group>/<pkg>/.
Every package is named @deepseek-ai/dsh-<pkg>; the group dir is a
pure container (no package.json). See packages/README.md and each
group's README.md for the product-vs-support split.
core/ product API spine
session/ event-sourced session log + in-memory store
system-prompt/ prompt-section + tool-schema assembly registry
tools/ tool registry + tools/pre-execute/post-execute pipeline
agent/ Agent interface, registry, agent/* event vocabulary
agent-loop/ THE concrete plugin: ReactLoopAgent + the loop driver
agent-core/ bundle plugin: the providerless/executor-less/UI-less spine
(timer+llm+sessions+system-prompt+tools+agents+invariants+
tool-bash+agent-loop) as code; forwards agent-loop's `agents`
llm/ LLM capability family
llm/ abstract LLM service + content-block vocabulary
llm-deepseek/ DeepSeek API adapter (hand-rolled fetch/SSE)
llm-pi-ai/ DeepSeek adapter via @earendil-works/pi-ai (design twin)
bash/ bash capability family
bash/ abstract bash executor seam (ctx.bash) — interface only
bash-local/ local-subprocess BashExecutor implementation
tool-bash/ model-facing bash/bash_output/bash_kill tool schemas
compact/ compaction capability family
compact/ abstract compaction seam (ctx.compact); backend + tool deferred
subagent/ subagent capability family
subagent/ provider-registry seam (ctx.subagents)
subagent-inprocess/ shared in-process run driver (library, registers nothing)
subagent-spawn/ in-process fresh-child backend
subagent-fork/ in-process backend seeded from the parent's completed-turn prefix
subagent-acp/ out-of-process child over ACP
tool-subagent/ model-facing delegation tool over ctx.subagents
todo/ todo/planning capability family
tool-todo/ model-facing todo_write tool: writes the whole task list to
the session log (todo/write), rendered as a stdio checklist /
ACP plan
hooks/ hook bridges + shared wire protocol
hook-protocol/ shared Claude Code / Codex hook wire-protocol core (library,
not a plugin): matcher primitive, exit-code/stdout codec,
runHook (via ctx.bash), most-restrictive merge, hook/* events
hooks-claude/ bridge plugin: runs a Claude Code hooks.json / settings on the
interception seams (CC dialect — env + ${CLAUDE_PLUGIN_ROOT}
substitution, per-event stdin payloads, outcome→Decision map)
hooks-codex/ bridge plugin: runs a Codex hooks.json on the seams (Codex
dialect — a 5-event, regex-only, block-only, no-substitution
subset of the CC protocol)
session-persistence/ persistence capability family
session-persistence/ durable persistence seam + write coordinator
session-persistence-jsonl/ JSONL-sidecar backend
session-persistence-sqlite/ SQLite backend
ui/ product integration surfaces
acp/ Agent Client Protocol bridge: drive the agent from an ACP
editor (Zed) over JSON-RPC stdio
stdio-agent/ stdio chat APP: agent-core spine + console logger + readline
UI + a pre-created main agent + a bin (the demo:echo/repl
front door)
acp-agent/ ACP server APP: agent-core spine + JSONL persistence + the
acp bridge, NO stdout logger + a bin (the demo:acp front door)
support/ dev/test/example infrastructure (lower compat expectations)
invariants/ dev-mode event-contract invariants + session-log freeze
ui-stdio/ minimal stdio (readline) UI plugin: renders agent/* events,
feeds stdin lines to the agent (shared by the demos)
llm-replay/ record/replay adapter: short-circuits llm/stream from a
recorded session JSONL (keyless snapshot tests)
subagent-mock/ scripted SubagentProvider for deterministic seam/tool tests
util/ low-level zero-dependency utilities shared across groups
brand/ type-only Branded<B> nominal-typing primitive (no runtime
code, no harness deps; owns the brand for cross-boundary ids)
examples/ Runnable demos (not workspaces; see examples/AGENTS.md). Each is a
THIN leaf cordis.yml: it picks the swappable backends (an LLM adapter,
a bash executor), loads ONE app package (dsh-stdio-agent or
dsh-acp-agent), and may add optional product tools or demo-local
teaching plugins. The app package bundles the agent-core spine +
front-door cluster + boot glue (a bin). No start.ts. echo-agent =
mock model + echo tool on dsh-stdio-agent (pnpm run demo:echo, no
key). coding-agent = the REPL agent demo: DeepSeek V4 + fs tools
(read/write/edit) + bash tools + subagent + todo_write on the same
app (pnpm run demo:repl, needs DEEPSEEK_API_KEY). acp-agent = the
ACP server agent demo on dsh-acp-agent (pnpm run demo:acp,
needs DEEPSEEK_API_KEY).
cordis.snapshot.yml = the acp leaf with llm-replay for keyless
snapshot replay.
docs/ architecture.md — the design doc. module-graph.md — generated
inter-package dependency graph (Mermaid; `pnpm run gen-module-graph`).
rfc/ — design decisions and proposals, one kind of doc grouped by
lifecycle (proposed/ implemented/ rejected/) then by class
(feature/ bug-fix/ simplification/ architecture/ process/ testing/);
the why behind vendoring, event-sourcing, the schema DSL, …. See
rfc/README.md.
postmortem/ — incident write-ups: a bug that escaped to a
user/merge/release, why the safety nets missed it, the guardrails added.
cookbook/ — step-by-step guides: adding a package, a tool,
an LLM adapter.
scripts/ repo maintenance scripts (vendor-manifest guard, publint runner).
JS bundling is tsdown (root tsdown.config.ts + two per-package
overrides in vendor/).
vendor/ Vendored Cordis source — manifest + sync procedure in vendor/README.md
packages/ Harness packages at packages/<group>/<pkg>/, all named @deepseek-ai/dsh-<pkg>
core/ product API spine: session, system-prompt, tools, agent, agent-loop, agent-core (the bundle)
llm/ LLM seam + the DeepSeek adapters (hand-rolled + pi-ai design twin)
bash/ bash executor seam + local impl + model-facing bash tools
fs/ filesystem seam + local impl + policy gate + read/write/edit tools
web/ web seam + search/fetch providers + model-facing web tools
compact/ compaction seam + basic backend
subagent/ subagent seam + spawn/fork/ACP backends + delegation tool
todo/ the todo_write tool
hooks/ Claude Code / Codex hook bridges + shared wire-protocol library
session-persistence/ persistence seam + JSONL/SQLite backends
ui/ ACP bridge + the stdio/ACP app packages (each with a bin)
support/ dev/test infrastructure: invariants, ui-stdio, llm-replay, subagent-mock
util/ zero-dependency utilities (Branded<B>)
examples/ Runnable demos: thin cordis.yml leaves over the app packages (see examples/AGENTS.md)
docs/ architecture, generated catalogs, RFCs, postmortems, cookbook (see docs/AGENTS.md)
scripts/ repo gates and generators
```
Per-package map: the group READMEs, indexed from [packages/README.md](packages/README.md).
## Commands
```sh
pnpm install # pnpm workspaces, node >= 24
pnpm run test # vitest run (packages|examples/*/tests/**/*.spec.ts)
pnpm run test:coverage # vitest run --coverage (per-file 100% gate on packages/*/*/src)
pnpm run test:e2e # real-API tests (packages|examples/*/tests/**/*.e2e.ts);
# self-skips without DEEPSEEK_API_KEY — see Secrets below
pnpm run test:snapshot # ACP snapshot tests (examples/*/tests/**/*.snapshot.ts):
# boot the real acp-agent subprocess, replay a recorded
# session JSONL, diff the normalized stdout + re-persisted
# log against committed goldens. KEYLESS — runs in the
# default gate. Filter one by scenario name (no `--`, which
# vitest treats as a positional file filter): `pnpm run
# test:snapshot -t <name>`.
pnpm run test:snapshot:record # re-record fixtures + goldens against the real
# API (needs DEEPSEEK_API_KEY); accept-the-diff = re-record
# (or `pnpm run test:snapshot -u` to refresh goldens only)
pnpm run typecheck # tsc -b tsconfig.json
pnpm run lint # eslint .
pnpm run lint:fix # eslint . --fix
pnpm run build # tsc emits lib/types, then tsdown bundles runtime lib/index.*
pnpm run knip # dead-code / unused-dependency check
pnpm run publint # package.json publish-correctness check (every packages/*/* package)
pnpm run hygiene # knip + publint + workspace constraints + NodeNext type-consumer check
pnpm run doc-typecheck # typecheck every ```ts block in README.md, docs/**/*.md,
# packages/*/*.md + packages/*/*/*.md (doc/code drift gate)
pnpm run gen-cordis-catalog # regenerate docs/cordis-catalog/events-and-services.md
# (events + services) from the interface Events / Context source
pnpm run verify-cordis-catalog # assert that generated catalog is not stale
pnpm run verify-md-wrap # assert no hard-wrapped prose paragraphs in README.md,
# docs/**/*.md, packages/*/*.md, AGENTS.md (one line per paragraph)
pnpm run verify-doc-refs # assert every docs/*.md path cited in a packages|examples
# TypeScript comment resolves (catches a moved/renamed doc)
pnpm run verify-package-paths # assert every packages/<path> cited in Markdown or a
# TypeScript comment resolves when it names a real (moved) package
pnpm run verify-rfc-classification # assert every RFC lives in a valid
# {lifecycle}/{class}/ folder and docs/rfc/README.md lists it
# under the matching heading (closed class set + index completeness)
pnpm run verify-translation-pairing # assert the bilingual pairing contract
# (docs/i18n/README.md): required docs have a complete pair
# (foo.md + foo.zh.md + foo.i18n.yaml); every pair matches its
# recorded consistency hashes, is switcher-linked, and
# structure-matched. `--list` prints the work list; `--write`
# re-records a pair after you bring both sides in line
pnpm run verify-node-next-types # assert built declarations typecheck for a
# standard external NodeNext ESM TypeScript consumer
pnpm run doc-sync # doc-typecheck + verify-cordis-catalog + verify-tool-catalog + verify-md-wrap + verify-md-links + verify-doc-refs + verify-package-paths + verify-rfc-classification + verify-type-equiv + verify-translation-pairing (CI runs this)
pnpm run demo:echo # run examples/echo-agent (no API key; type "echo hi" to
# see a tool call) — the mock skeleton
pnpm run demo:repl # run examples/coding-agent — the REPL agent demo
# (needs DEEPSEEK_API_KEY; give it a coding task)
pnpm run demo:acp # run examples/acp-agent — the ACP server agent demo
# over JSON-RPC stdio (needs DEEPSEEK_API_KEY;
# drive it from Zed or another ACP client)
pnpm install # pnpm workspaces, node >= 24
pnpm run test # vitest unit tests
pnpm run test:coverage # THE gating test run: per-file 100% coverage on packages/*/*/src
pnpm run test:e2e # real-API tests; self-skip without DEEPSEEK_API_KEY
pnpm run test:snapshot # keyless ACP replay vs committed goldens; filter one: pnpm run test:snapshot -t <name>
pnpm run test:snapshot:record # re-record goldens against the real API (needs key)
pnpm run typecheck
pnpm run lint
pnpm run build # tsc emits lib/types, tsdown bundles runtime
pnpm run hygiene # knip + publint + workspace constraints + NodeNext consumer check
pnpm run doc-sync # all documentation gates; see the doc-sync script in package.json
pnpm run demo:echo # mock-model REPL, no key needed
pnpm run demo:repl # real REPL coding agent (needs DEEPSEEK_API_KEY)
pnpm run demo:acp # ACP server agent over JSON-RPC stdio (needs DEEPSEEK_API_KEY)
```
### Run the CI gates locally BEFORE marking a PR ready
### Run the CI gates locally before marking a PR ready
CI is the backstop, not the first place a gate runs. Before you open a non-draft PR or move one from draft to ready, run the same gates CI runs, on your own tree, and confirm they pass — do not lean on CI (or a Codex pass) to discover a red gate you could have caught locally. The CI-equivalent local run is:
CI is the backstop, not the first place a gate runs. From a fresh clone or worktree, run `pnpm run build` once first — publint and the NodeNext check validate built `lib/`. The CI-equivalent run:
```sh
set -euo pipefail
@@ -231,83 +72,49 @@ rm -rf .sessions
pnpm exec vitest run --config vitest.e2e.config.ts packages/ui/stdio-agent/tests/built-bin.e2e.ts packages/ui/acp-agent/tests/built-bin.e2e.ts
```
**`pnpm run test:coverage`, NOT `pnpm run test`, is the gating test command.** `pnpm run test` runs `vitest run` with no coverage; CI's node job runs `test:coverage`, which enforces a **per-file 100%** threshold on `packages/*/*/src`. A suite that is green under `test` can still fail CI on an uncovered line — and that uncovered line is often *dead code* the 100% gate is correctly flagging for deletion (see [§ Defensive patterns](#defensive-patterns-hard-won) "Line coverage is not behavior coverage"), not a missing test to bolt on. `hygiene` (knip + publint + workspace constraints + NodeNext types) and `test:snapshot` (keyless ACP replay) are likewise CI gates that `test` alone does not cover. When you rely on a Codex convergence pass for sign-off, check WHICH commands it ran: a pass that ran `test` but not `test:coverage`/`hygiene`/`doc-sync` has not exercised those gates.
`test:coverage`, not `test`, is the gating run ([why](docs/testing.md)); a review sign-off counts only for the commands it actually ran.
## Secrets / .env
Real-API e2e tests (`pnpm run test:e2e`) read `DEEPSEEK_API_KEY` (and optionally `DEEPSEEK_BASE_URL`) from the environment, or from a gitignored `.env` at the repo root loaded via Node's native `process.loadEnvFile()`:
```
DEEPSEEK_API_KEY=sk-…
DEEPSEEK_BASE_URL=https://… # optional; defaults to the public API
```
cordis.yml configs reference env vars with the `!!js` tag: `apiKey: !!js process.env.DEEPSEEK_API_KEY`. Never commit real credentials; CI has no secrets and e2e suites must self-skip without them.
**Lean on with-key e2e tests — we are DeepSeek and model inference is cheap.** A no-key test (mock adapter, or an operation that never reaches the model) is great for determinism and CI, but it can only prove the plumbing, not that the agent actually *works* against a real model. Do not ration real-API tests to save tokens: write many of them, cover the real flows (a real prompt that writes a file, a multi-turn conversation, tool use, cancellation mid-stream), and run them frequently while developing — locally and whenever you have a key in the environment. **Especially smoke tests**: a cheap with-key smoke test that boots the real example, sends one real prompt, and checks the world (a file on disk, a non-empty assistant turn) catches whole classes of "green unit tests, broken product" failures that mocks structurally cannot — the very gap that let the ACP inject bug ship (see [docs/postmortem/0001](docs/postmortem/0001-acp-default-export-drops-inject.md)). The self-skip rule is ONLY so CI (which has no secrets) stays green and so a contributor without a key isn't blocked — it is not a signal that real-API tests are expensive or second-class. When in doubt, add the with-key test AND run it.
Dev/test/demo run **unbuilt** via tsx + the source `paths` map in the root `tsconfig.json` (`vitest` resolves through that same root config). Building is only needed for publishing/consumption outside the repo. Non-published code (`examples`, tests, and scripts) is checked by root `tsconfig.json`, which sets `noEmit` and references the package/vendor graph so those sources stay checked under their own tsconfig boundaries.
Real-API tests and demos read `DEEPSEEK_API_KEY` (and optional `DEEPSEEK_BASE_URL`) from the environment or a gitignored root `.env` loaded via `process.loadEnvFile()`. cordis.yml references env vars with the `!!js` tag (never `!js`). Never commit credentials. CI has no secrets, so e2e suites self-skip without a key — a CI accommodation, not a cost signal; the with-key policy is in [docs/testing.md](docs/testing.md).
## Conventions
- **Package naming**: every npm package in this repo is `@deepseek-ai/dsh-<name>` (vendored packages keep their upstream names and are `private: true`).
- **ESM everywhere** (`"type": "module"`); imports between workspace packages use package names, never relative paths across package boundaries. In-package relative imports use explicit `.ts` extensions; `rewriteRelativeImportExtensions` turns those into `.js` in emitted JS, while declarations keep explicit `.ts` specifiers that NodeNext/Node16 TypeScript consumers can resolve to sibling `.d.ts` files. `lib/types/**/*.js` is a bundler-only intermediate, not a Node ESM entrypoint.
- **`cordis` is a peerDependency** (+ devDependency) of every harness package, mirroring upstream convention.
- **Registrations are effects**: anything a plugin contributes (adapter, tool, section, agent, event listener) goes through `ctx.effect()` / `ctx.on()` so disposal and HMR work. If you write a registry, `register()` must return the disposer.
- **Typed events via declaration merging**: services declare their events in `declare module 'cordis' { interface Events { … } }`, and their ctx key in `interface Context`. Extensible unions use the merge-extensible-map pattern (see `ContentBlockMap`, `MessageSourceMap`).
- **Waterfall semantics**: `ctx.waterfall` listeners receive `(...args, next)` and MUST call `next()` to delegate; returning without it short-circuits. This is the veto mechanism — use deliberately.
- **Discriminated unions: match, don't chain**: branch on a tagged union (`StreamChunk`, `FinishReason`, `SessionEvent`, …) with a `switch` on the tag, not a chain of `if (x.kind === '…')`. The switch narrows each arm so member-only fields (`finish.message`, `finish.code`) are reachable in the right case and a typo'd tag fails to compile. Prefer extracting a small typed helper (`finishError(finish: FinishReason)`) over inlining the branches at the call site.
- **Switch exhaustiveness**: switches over CLOSED unions (e.g. `StreamChunk`) end with `default: assertNever(value, 'context')` (from dsh-llm) so adding a variant breaks compilation at every switch that must handle it. Switches over MERGE-EXTENSIBLE unions (`SessionEventMap`, `ContentBlockMap`, `FinishReason`, …) must NOT use assertNever — plugin-added variants are valid unknown values; handle known cases and fall through `default` with a comment (the lint rule `switch-exhaustiveness-check` makes the choice explicit either way; a redundant disable directive is itself a lint error).
- **Plugins, not loop changes**: new behavior goes into a plugin on the documented extension seams (see the plugin sanity checklist in docs/architecture.md). Changing `agent-loop` requires updating that doc.
- **Capability seams are three packages**: when adding a swappable capability (an execution backend, a provider integration, …), split it into *interface* (abstract service + vocabulary types, e.g. `bash/`), *implementation* (a concrete subclass, e.g. `bash-local/`), and *consumer* (what the model/plugins see, e.g. `tool-bash/`). Implementations and consumers then evolve independently — a sandboxed executor replaces `bash-local` without touching tool schemas. The LLM seam follows the same shape (`llm/` is interface + consumer surface; adapters are implementations). See docs/architecture.md § "Capability seams" for when NOT to split.
- **Explicit > implicit at package seams**: interface/vocabulary types spell out every field a consumer must supply — no optional field that the implementation silently fills with a hidden `?? default`. Put defaulting in the owning implementation as an explicit step (a `resolve(request): Spec` method that turns the optional-field request into the required-field spec), not smuggled inside `run()`/`start()`. Example: `dsh-bash` splits `BashExecRequest` (optional `workdir`/`timeoutMs`, model-facing) from `BashExecSpec` (required, what `run`/`start` act on); the tool layer calls `ctx.bash.resolve()` between them. The reader of a `BashExecSpec` never has to wonder where the working directory came from.
- **Opaque cross-boundary ids are branded, never bare `string`**: an identity that crosses a package seam and that a consumer must store-and-return but never parse (a backend-defined version token, a target key, a task/session/call id) is a `Branded<B>` from `@deepseek-ai/dsh-brand` with a same-named cast factory in the owning package — a zero-cost compile-time guard so semantically-distinct strings stop being interchangeable. Not every string needs it: author-readable names (`ToolName`) and closed code unions (`ErrorCode`) don't. See [Branded IDs everywhere they belong](docs/rfc/implemented/architecture/2026-06-20-branded-ids.md).
- **An empty `catch` must name what it swallows and why nothing else can hit it**: a bare `catch {}` hides bugs. When you deliberately ignore a throw, the comment must (a) name the single expected failure, (b) say why ignoring it is correct — usually because the useful state was already captured *before* the `try` — and (c) make clear nothing else of consequence can reach the catch (ideally the `try` wraps a single statement). Example: the error-body `response.json()` parse in `dsh-llm-deepseek`'s adapter sets `code` + HTTP `status` from the status line before the `try`, so a malformed provider body can only cost a richer message, never the real error.
- **Symmetry is usually more correct**: when two related values play parallel roles (a test fixture and its expected output, a request shape and its response shape, a buggy input and the test that checks the fix), give them parallel form — both named consts, or both inline, not one each way. Asymmetry is a smell that usually points at a missed extraction.
- **Merging PRs**: always merge with a **merge commit** (`gh pr merge --merge`), never squash or rebase. The per-PR commit history is intentional — review-fix commits, regression-test commits, and the reasoning in each message are part of the record — and squashing flattens it away.
- **Never rewrite a pushed branch in a stacked chain.** Once a branch is pushed (and especially once it has a PR), do NOT `rebase`, `amend`, or force-push it. Update a child branch by **merging its parent down** (`git merge <parent-branch>` into the child, as a new merge commit), never by rebasing the child onto the parent's new tip. Rewriting a shared branch diverges it from what the parent and GitHub recorded, which breaks the stacked-merge graph and erases the review-fix history that documents what each round caught. Amending is fine ONLY for your own not-yet-pushed, not-yet-reviewed work. A corollary on WHERE a fix lands: a review fix belongs on the PR that **introduced** the issue, even when a downstream PR in the stack also carries the affected file — fix it on the originating branch, then merge that branch DOWN the chain, rather than originating the fix on the downstream PR (where it would be invisible to a reviewer of the PR that actually owns the code).
- **TODO markers**: use `FIXME`/`TODO`/`XXX` to flag known issues by urgency — see [docs/development.md](docs/development.md) for the semantics of each.
- **Tests**: vitest, colocated under `packages/<group>/<pkg>/tests/*.spec.ts`. Every registry needs an HMR-safety test (dispose the contributing fiber, assert cleanup). **Excessive tests are welcome** — when in doubt, write the test; err on the side of covering edge cases, error paths, event ordering, and concurrency races even if they seem unlikely. Review findings get regression tests (see `packages/core/agent-loop/tests/review-fixes.spec.ts`). The same generosity applies to **real-API (with-key) e2e tests — inference is cheap here (we are DeepSeek), so do not ration them**: cover the agent's real flows (a real prompt that writes a file, multi-turn, tool use, cancellation) and run them frequently while developing, especially cheap **smoke tests** that boot the real example and check the world. A green mock/no-key suite proves the plumbing, not the product — the with-key smoke test is what catches "green units, broken product". See § Secrets / .env for the with-key policy and why self-skip is a CI accommodation, not a verdict that real-API tests are expensive.
- **Prefer the REAL implementation over a mock/stand-in in tests.** When the genuine collaborator is available in the repo, wire it up instead of hand-rolling a fake — a test that registers an inline `defineTool({ name: 'bash', … })` to stand in for `dsh-tool-bash` proves the *bridge* moves bytes but not that the *shipping tool* renders the way the test asserts; the two drift and the test passes while the product is wrong. Mock only the genuinely expensive/non-deterministic boundary (the LLM adapter, the network, the clock) and keep everything downstream real: a bridge tool-call test runs the scripted mock MODEL but the REAL tool + REAL executor (e.g. `makeBridgeHarness({ withBash: true })` plugs `dsh-bash-local` + `dsh-tool-bash` and runs an actual `echo`), so it verifies the actual `presentCall`/`presentResult` an editor sees. This is the unit-test echo of "verify the world, not a synthetic stand-in" (see § Defensive patterns) — a fake you wrote will agree with whatever you assumed; the real thing won't.
- **A change that affects the editor-facing transcript or end-to-end agent UX needs a snapshot test (or an explicit note in the PR why none applies).** The snapshot tier (`examples/*/tests/**/*.snapshot.ts`, `pnpm run test:snapshot`) boots the real example subprocess, replays a recorded session JSONL deterministically (keyless), and diffs the normalized stdout transcript + re-persisted session log against committed goldens — the full-transcript regression net that mock-level unit tests structurally cannot be (it is what catches a bridge-translation or loop-structure regression that leaves every unit green). When you change the ACP bridge, the agent loop's observable output, tool presentation, or anything an editor renders, add or update a scenario under `examples/acp-agent/tests/snapshots/` and re-record with `pnpm run test:snapshot:record`. Reviewing the golden diff is part of the review. The rule is scoped to transcript/UX-affecting changes — a pure internal refactor with no observable-output change does not need one, but say so. See [docs/rfc/implemented/testing/2026-06-19-acp-snapshot-tests.md](docs/rfc/implemented/testing/2026-06-19-acp-snapshot-tests.md).
- **A tool's editor/ACP representation is part of its design — decide it up front, not after.** When you add or change a model-facing tool, its ACP tool-call card is as much a deliverable as its `execute`: decide which render intent it declares via `presentCall`/`presentResult` (`generic` — a titled card with `kind`/`rawInput`/`content`/`locations`; `terminal` — a shell command; `diff` — a file create/modify rendered as an inline diff), and cover it with a snapshot test (the transcript tier is the only place card rendering is actually verified end-to-end — a unit test on the pure presenter proves the shape, not that an editor renders it). A tool that reads/writes files should almost always emit `locations` (for editor follow-along) and, for a mutation, a `diff` card; a tool that runs a command is a `terminal`. The presentation methods are pure functions of `args` (they run on live streaming AND session-log replay), so they must not do I/O or read session state — the bridge, not the tool, relativizes display paths and fills the session cwd. The reference implementations are `dsh-tool-fs` (generic/diff) and `dsh-tool-bash` (terminal); the vocabulary and the why are pinned in [docs/rfc/implemented/architecture/2026-07-02-tool-render-intent-union.md](docs/rfc/implemented/architecture/2026-07-02-tool-render-intent-union.md), and the step-by-step is in [docs/cookbook/adding-a-tool.md](docs/cookbook/adding-a-tool.md). When you introduce a new capability seam, a new agent-lifecycle shape, or anything that produces an observable transcript (a new tool family, a subagent transport, a new UI surface), the plan must name how it will be covered at EVERY tier it touches — unit, real-API e2e, AND the full-transcript snapshot tier — and, critically, must check that the existing test infrastructure can actually express that coverage. Do not assume a snapshot/e2e harness built for one shape (e.g. a single top-level ACP session) transparently supports a new shape (e.g. a parent agent driving nested child agents): verify it, and if it cannot, the harness extension is in-scope work to plan and schedule, not a detail to discover mid-implementation. This rule exists because a real plan under-scoped exactly this: the subagent backends were planned with unit + e2e coverage but the snapshot tier turned out to assume one session per process (`dsh-llm-replay`'s single positional cursor, single-file harvest), so nested-agent snapshot coverage became unplanned net-new infrastructure (`TODO(subagent-snapshots)`). The cost of finding that during design is a paragraph; the cost of finding it mid-build is a re-plan. When the harness gap is large enough to be its own reviewable unit, schedule it as a dedicated stacked follow-up with its own RFC — but SAY SO in the originating plan, with the gap named, rather than letting it surface as a surprise.
- Every npm package is `@deepseek-ai/dsh-<name>`; vendored packages keep upstream names and are `private: true`. `cordis` is a peerDependency (+ devDependency) of every harness package.
- ESM everywhere (`"type": "module"`). Cross-package imports use package names, never relative paths; in-package relative imports use explicit `.ts` extensions. Dev/test/demo run unbuilt via tsx + the root tsconfig `paths` map; building is only for consumers outside the repo.
- **Registrations are effects**: every contribution goes through `ctx.effect()` / `ctx.on()`; a registry's `register()` returns the disposer. Every registry gets an HMR-safety test.
- **Typed events via declaration merging**; extensible unions use the merge-extensible-map pattern (`ContentBlockMap`, `SessionEventMap`, …). Every new event's JSDoc carries an `@mode` tag — the catalog generator hard-errors without it; mode semantics are in the [generated catalog](docs/cordis-catalog/events-and-services.md) header and [the catalog RFC](docs/rfc/implemented/process/2026-06-20-generated-cordis-catalog.md).
- **Discriminated unions: `switch` on the tag**, not if-chains. Closed unions end with `default: assertNever(...)`; merge-extensible unions must NOT — handle known cases and fall through `default` with a comment.
- **Waterfall listeners MUST call `next()`** to delegate; returning without it is the veto ([semantics](docs/architecture.md#cordis-waterfall-semantics-important)).
- **Plugins, not loop changes**: new behavior goes on the documented extension seams; changing `agent-loop` requires updating docs/architecture.md.
- **Capability seams are three packages** — interface / implementation / consumer ([capability seams](docs/rfc/implemented/architecture/2026-06-13-capability-seams.md)); don't split preemptively.
- **Explicit > implicit at package seams**: no optional field silently filled by a hidden `?? default` inside `run()`; defaulting is an explicit `resolve(request): Spec` step in the owning implementation (the `dsh-bash` request/spec split is the template).
- **Opaque cross-boundary ids are branded** (`Branded<B>` from `dsh-brand`), never bare `string` ([branded IDs](docs/rfc/implemented/architecture/2026-06-20-branded-ids.md)).
- **An empty `catch` names what it swallows** and why nothing else can reach it; keep the `try` to one statement.
- **Symmetry is usually more correct**: parallel values get parallel form; asymmetry is a smell for a missed extraction.
- **Tests document behavior, not golden truth**: a green test pins what the code DOES, not what it SHOULD do. Before preserving a behavior solely for its test, ask whether it is load-bearing; an artifact changes together with its test, with the why in the PR ([worked example](docs/rfc/implemented/simplification/2026-06-19-drop-mutable-session-summary.md)).
- **RFCs are proposals, not golden truth**: validate its premise against current code before implementing; friction is evidence of over-reach — amend on the way to `implemented/` ([worked example](docs/rfc/implemented/simplification/2026-06-20-public-agent-stop-surface.md)).
- **Testing policy** — tiers, with-key generosity, real-over-mock, world-verification, real-load-path and published-bin guards: [docs/testing.md](docs/testing.md). A transcript/UX-affecting change needs a snapshot test, or a PR note why none applies.
- **A tool's ACP render intent is part of its design**, decided up front (`generic`/`terminal`/`diff`, `locations`); presentation methods are pure functions of `args` ([render-intent RFC](docs/rfc/implemented/architecture/2026-07-02-tool-render-intent-union.md), [cookbook](docs/cookbook/adding-a-tool.md)).
- **A new capability seam, lifecycle shape, or transcript surface names its coverage at every tier (unit, e2e, snapshot) at plan time** and verifies the harness can express it — a gap is scheduled work, not a mid-build surprise.
- **Merge PRs with merge commits** (`gh pr merge --merge`), never squash/rebase. **Never rewrite a pushed branch**; update a child by merging its parent down. **A review fix lands on the PR that introduced the issue, as a separate commit**, then merges down ([stacked-review guide](docs/cookbook/responding-to-pr-review-on-a-stack.md)).
- TODO markers by urgency: `FIXME` / `TODO` / `XXX` ([semantics](docs/development.md)).
- Files end with exactly one trailing newline; `git diff --check` (pre-push) gates it.
## Defensive patterns (hard-won)
## Defensive patterns
Each bullet is a bug class that bit us; the rule prevents the reoccurrence.
[docs/defensive-patterns.md](docs/defensive-patterns.md) carries the hard-won bug-class rules: report orthogonal outcomes independently; honor cross-seam contracts on both sides; async state is not synchronous state; dispose must reach quiescence; contain callback exceptions; never hand untrusted output the ambient environment or predictable paths. Read it before writing lifecycle, concurrency, subprocess, or teardown code.
- **Report orthogonal outcomes independently.** A result can be several things at once (a process can both time out AND exit 0 because it trapped the signal). Don't nest the report of one flag inside the branch of another. Surface each independent fact (`timedOut`, `signal`, `exitCode`) on its own so a caller never reads a cut-short run as a clean success.
- **Honor cross-seam contracts on BOTH sides.** When an interface documents two valid ways to signal something (e.g. an adapter may report a model failure by THROWING from `stream()` *or* by ending the stream with a `finish {kind:'error'|'aborted'}` chunk), the consumer must handle both — not just the one the first implementation happened to use. A library-backed adapter that can't throw mid-stream relies on the finish-chunk path; if the loop only catches throws, a provider 401 becomes a normal completed turn. Document the contract where the type is defined and exercise every branch through the real consumer in tests.
- **Async state is not synchronous state.** `agent.send()` does not flip status to `running` before it returns; a background task's completion races turn boundaries; `reader.close()` fires for both EOF and disposal. Never gate control flow on a status you only *just* requested. Drive lifecycle off the events/promises that actually fire (`agent/status`, `task.done`), and when "done" needs a settle signal, observe the transition (saw `running` THEN `idle`) rather than counting actions you assume map 1:1 to turns — the loop batches queued messages into one turn. But a settle-signal guard cuts both ways: if the awaited transition can *never* occur (EOF with no work submitted → no turn ever starts → never `running`), it hangs forever. Always handle the "nothing to wait for" branch explicitly alongside the "wait for the work" branch.
- **Dispose must reach quiescence, not just request it.** A teardown that issues kills/aborts but returns before the work stops leaves orphans. Make cleanup `async` and `await` the children's exit (kill → await `done`), and close listener/notification registries *before* killing so late completions stay silent. Tests must prove disposal *waited* (pid already gone right after `await fiber.dispose()`), not merely that the process eventually dies.
- **Contain callback exceptions at the boundary.** A user-supplied listener (`onTaskDone`, event handlers) that throws must not reject the promise it runs inside or starve the listeners after it. Wrap the dispatch loop in try/catch and log; never let one bad subscriber break core lifecycle.
- **Never hand untrusted/model output the ambient environment or predictable paths.** Spawned commands get a scrubbed env (drop `*KEY*`/`*SECRET*`/ `*TOKEN*`) so the harness's own credentials can't leak into output, `env`, or spill files. Temp/spill files use a private (0700) dir, random names, and exclusive owner-only (`'wx'`, `0o600`) opens — predictable world-readable paths invite symlink races and disclosure.
- **e2e tests own their resources.** Real-API/integration tests must create the harness in the test and dispose it in `afterEach` (even on failure/retry/timeout), so a flaky run doesn't leak processes or contexts. Shared fixtures live in a plain `tests/harness.ts` module, NOT another `*.e2e.ts` file — importing a spec file re-registers its `describe` and duplicates real API calls. Verify the WORLD, not the agent's self-report: re-run the command/check externally and assert files are byte-identical where they should be unchanged (a keyword probe lets a cheating agent pass).
- **Line coverage is not behavior coverage; test the REAL entry path, not a synthetic stand-in.** 100% per-file coverage and a green suite are necessary, not sufficient — they prove lines ran, not that the feature works the way it ships. A plugin shipped via `cordis.yml` is loaded by the cordis Loader, which calls `Loader.unwrapExports` (`exports.default ?? exports`) and then constructs a fiber from the module's `inject`/`name`/`Config` namespace exports. A test that mounts the plugin by hand-building `ctx.plugin({ name, inject, apply })` (or even `ctx.plugin(NamespaceImport)`) BYPASSES `unwrapExports` entirely, so it cannot catch a broken export shape. This bit us hard: a stray `export default apply` made `unwrapExports` collapse the module to the bare function, dropping `inject` — so every service read threw `cannot get property … without inject` the instant a real editor connected, while 178 hand-mounted tests stayed green. The guard is at least one test that drives the plugin through its REAL load path (a subprocess booting the example via the Loader, or the Loader API directly), exercising the headline operations end-to-end. It runs WITHOUT a key when the operation doesn't call the model (`session/new`/`session/load` reach the factory but never the LLM), so there is no excuse to skip it. Corollary: when an `*.e2e.ts` spawns the example from a temp cwd, set `TSX_TSCONFIG_PATH` to the repo-root tsconfig — the unbuilt `paths` map is found by searching UP from cwd, so a temp cwd outside the repo silently falls back to built `lib/`, which both hides source changes and only "works" when a stale build happens to exist. Two sharper corollaries this bit us with again:
- **A real-load-path test only GUARDS the export shape if a broken shape actually FAILS it.** The original crash (`cannot get property … without inject`) fired because that plugin HAS `inject`. A plugin with NO `inject` (a composition/bundle plugin that mounts children carrying their own inject, e.g. `dsh-agent-core` and the app packages) does NOT crash on a stray `export default` — `unwrapExports` silently drops `Config`/`name` and the plugin boots anyway — so a Loader smoke stays green while the export shape is broken. For such plugins add an EXPLICIT assertion that the regression fails: `expect('default' in mod).toBe(false)` plus running the module through the real `Loader.prototype.unwrapExports` and asserting `name`/`Config`/`apply` survive. Prove it: add `export default apply`, watch the test go red, revert.
- **"Real entry path" means the PUBLISHED ARTIFACT, not the dev runtime.** A test (or a `demo:*` smoke) that boots `src/bin.ts` under `tsx` is NOT the same code a consumer runs — the package `bin` field points at the built `lib/bin.js` under plain `node`. tsx masks failure modes the published artifact has: a boot settle-race that exits 0 before the app's handles attach, module-resolution differences (the unbuilt `paths` map vs node_modules), and a load failure that `loader.await()`'s `Promise.allSettled` SWALLOWS so a typo'd config silently exits 0. The guard is a smoke that runs the built `lib/bin.js` under plain `node` in a node_modules-shaped temp dir (symlinked workspace + vendor packages), asserts the real output, AND asserts a genuinely-missing config exits NON-ZERO. The tsx demo is necessary but not sufficient; the published-bin smoke is what catches "green under tsx, broken on install".
- **Tag spelling and EOF hygiene.** cordis.yml interpolates env via the `!!js` tag (js-yaml resolves custom tags under `tag:yaml.org,2002:js`), not `!js` — keep code, comments, and docs consistent. Files end with exactly one trailing newline; `git diff --check` (a pre-push gate) rejects new blank lines at EOF.
## Type safety and documentation
## Type Safety and Documentation
Everything compiles under `strict: true` with `noImplicitAny`; every remaining `any` carries a comment saying why a narrower type is infeasible. Lean toward the stricter lint rule and the extra mechanical gate: encode invariants in checks (`verify-*` scripts), preferring a narrow justified escape hatch over a rule left off globally. Type gymnastics are acceptable inside core packages when they buy plugin-author DX (the `defineTool` schema DSL is the canonical example).
This codebase aims to be **very type-safe and well documented** for maintainability. Code that fails to compile under `strict: true` (with `noImplicitAny` enabled for all `packages/*/*` source) is not acceptable. Every `any` that remains must have a specific justification (a comment explaining why a narrower type is infeasible).
Docs are part of every change: code changes update their README and JSDoc in the SAME change; a bilingual-pair edit updates the counterpart and re-records ([i18n contract](docs/i18n/README.md)). The writing rules — document the current state never the history, one physical line per paragraph, one home per fact — and the word-budget gate live in [docs/AGENTS.md](docs/AGENTS.md).
**Almost always lean toward the stricter lint rule.** In the agentic-coding era the cost/benefit of strictness has inverted: a machine writes and reads most of the code, so the one-time cost of satisfying a stricter rule is cheap and paid by a tool, while the benefit — a whole class of error caught mechanically, a consistent foundation every agent can rely on, less reviewer attention spent on what a linter could have caught — compounds across every future change. When choosing whether to enable a rule, tighten an existing one, or add a new gate (a `verify-*` script, a constraint check), default to YES unless it has a concrete, recurring false-positive problem. Prefer a narrowly-scoped escape hatch (a justified inline disable with a reason, a per-path override) over leaving the rule off globally. The same reasoning motivates this repo's many bespoke gates (`doc-sync`, `verify-package-paths`, the workspace-shape constraint): encode the invariant in a check so no human or agent has to remember it.
## Editing these instructions
In the **core** packages (`packages/llm/llm`, `packages/core/tools`, `packages/core/agent`, `packages/core/agent-loop`, `packages/core/session`, `packages/core/system-prompt`), **type gymnastics are acceptable when they improve the DX of plugin authors** for common plugin types. The `defineTool` typed schema DSL in `dsh-tools` is the canonical example: the `SchemaSpec` to `InferArgs<S>` type-level mapping gives tool authors zero-cast typed `execute` args, and the cost of the conditional types stays inside the core package.
`AGENTS.md` is the real file; `CLAUDE.md` is a symlink to it (root, `packages/`, `examples/`). Edit `AGENTS.md`, never the symlink. This file is budget-gated (`verify-doc-budgets`): additions displace something or justify a ceiling raise in the PR.
Verbose documentation is fine **as long as docs and code stay strictly in sync**. Out-of-sync docs are worse than no docs. **When you change code, update its docs in the SAME change** — grep the package README and the module/JSDoc comments for the old behavior (config keys, defaults, error codes, wire field names, event names) and fix every hit. CI runs `pnpm run doc-sync` (`doc-typecheck` + `verify-cordis-catalog` + `verify-tool-catalog` + `verify-md-wrap` + `verify-md-links` + `verify-doc-refs` + `verify-package-paths` + `verify-rfc-classification` + `verify-type-equiv` + `verify-translation-pairing`), which typechecks every fenced `ts` block in `README.md`, `docs/**/*.md`, and `packages/*/*.md`, regenerates the cordis events/services catalog from source and fails if the committed copy is stale, asserts no hard-wrapped prose paragraphs, checks that every relative Markdown cross-link resolves, checks that every `docs/*.md` path cited in a source comment resolves, checks that every `packages/<path>` reference naming a real package resolves, checks that every RFC is filed under a valid class folder and listed in its index, checks that every ` ```ts type-equiv ` doc block still matches its source type, and checks the bilingual pairing contract (required docs have a complete, consistency-recorded EN/ZH pair — see [docs/i18n/README.md](docs/i18n/README.md)) — across those files plus `AGENTS.md` / `packages/AGENTS.md` — but that scope does NOT catch prose drift in `AGENTS.md` / `packages/AGENTS.md` / `packages/README.md` (config keys, defaults, error codes), so keeping those in sync remains on the author. The same-change rule extends to translations: **editing either side of a paired doc means updating the counterpart and re-recording the pair in the SAME change** (run the [dsh-translate-docs](.agents/skills/dsh-translate-docs/SKILL.md) skill, then `pnpm run verify-translation-pairing --write`); the pairing gate goes red otherwise. Every module has a module-level doc comment explaining its role. Every exported class, interface, type, function, and non-obvious method has a JSDoc that explains semantics (not just the name) — contracts (what events fire when), disposal behavior, error behavior, and extension intent. Internal helpers get docs only where non-obvious. Prefer one-liners when one line suffices.
## Vendoring policy
**Tag every new event with `@mode`.** The cordis events/services catalog ([docs/cordis-catalog/events-and-services.md](docs/cordis-catalog/events-and-services.md)) is GENERATED from source by `scripts/gen-cordis-catalog.ts` — never hand-edit it; run `pnpm run gen-cordis-catalog` and commit the result. When you add an event to an `interface Events` block, its JSDoc MUST carry a `@mode emit|waterfall|parallel|serial` tag (the generator hard-errors without it): use `waterfall` when the signature ends with a `next: () => …` parameter (the listener transforms or vetoes via `next()`), `parallel` when the loop awaits a fan-out and must run every listener (e.g. an awaited `Promise<void> | void` checkpoint like `session/flush`), `serial` when the loop awaits listeners in registration order and should isolate side effects (e.g. an ordered surface-mutation checkpoint like `agent/pre-step`; Cordis stops early if a listener returns a bail value, so `void` serial listeners must not return a semantic veto), and `emit` for plain fire-and-forget notifications. The generator also cross-checks the tag against the signature where the shape is conclusive (a trailing `next` ⇒ waterfall) and hard-errors on a contradiction. Write the rest of the event's JSDoc to stand alone — it is the catalog entry's prose.
**The core-data-structures catalog is a maintained surface, not a write-once artifact.** [docs/core-data-structures/](docs/core-data-structures/core.md) catalogs the spine vocabulary (core.md) and the per-seam types (sub-pages). When a change adds, removes, or reshapes a type the catalog documents — a new `…Map` variant, a new content-block or session-event type, a field on `GenerateOptions`/`Agent`/`ToolDefinition`/a bash type, or a whole new core/seam type — update the catalog in the SAME change: edit the prose, and for a pasted ` ```ts type-equiv ` block, re-copy it verbatim and keep `scripts/type-equiv.manifest.json` 1:1 with the blocks. The `verify-type-equiv` gate catches a *drifted paste* of an already-documented type, but it canNOT tell you a brand-new core type was never documented — that judgment is on the author and the reviewer. The definition of "core" (the spine-vs-seam line) is in [core.md § What counts as "core"](docs/core-data-structures/core.md#what-counts-as-core); a genuinely spine-level new type belongs in core.md, a new capability's vocabulary on a sub-page. See [development.md](docs/development.md#documenting-types-verbatim-ts-type-equiv) for the `ts type-equiv` mechanics.
**Document the CURRENT state — the "what" and "why" — never the PROCESS or HISTORY of how it got there.** A comment, JSDoc, or doc paragraph describes what the code *is* and why it is that way, as if it had always been so. Do NOT narrate the change that produced it: no "previously X, now Y", "changed from", "used to", "this replaces", "the old map", "renamed", "moved here", "as of this PR", or "(was …)". **In particular, NEVER name the change unit a reader cannot see — the PR, commit, or stack position that introduced the code — in a comment, JSDoc, OR a test name/description.** A `// (PR D's per-agent teardown)` aside, a `* Tests for the cancel primitive (PR C).` module doc, or an `it('… identity no longer matters')` title that only makes sense relative to a prior design are all the same violation: the reader of the current tree has no "PR D" or "old design" to anchor against, and the reference rots the moment the stack merges. Name the *mechanism* (`the session's AgentHandle teardown`), not the PR. Such phrasing rots the instant the next change lands, and a reader of the current code does not need the diff narrated in prose — that belongs in the commit message, the PR description, or an RFC (the durable home for "why we moved away from X"). Write "the owner token lives on the task in the executor" — not "ownership *now* lives on the executor instead of a plugin-local map". When a contrast genuinely aids understanding (a non-obvious choice between live alternatives), frame it against the alternative as a standing fact ("stored on the executor, NOT the tool plugin, so it survives an HMR reload"), not against the codebase's past. The same rule governs review-fix commits: the *commit message* records what the review caught; the *code comment* it touches states only the resulting truth. RFCs (`docs/rfc/`, grouped into `proposed/` / `implemented/` / `rejected/`) record the *why* behind choices a future reader would otherwise re-litigate (the vendoring policy, event-sourcing, the schema DSL are the existing examples). A PR that introduces such a decision — a new third-party runtime dependency over the vendoring default, a cross-package contract, a security/isolation model, a deviation from a documented architecture rule — writes the RFC in `implemented/` **in the same PR**, and links it from the relevant code. A proposal for future work not yet built goes in `proposed/`. A PR whose changes are mechanical, self-evident, or already covered by an existing RFC needs none — do not manufacture an RFC for a routine change. When unsure, the test is: would a competent maintainer six months from now ask "why was it done this way?" and be unable to answer from the code alone? If yes, write it. See [docs/rfc/README.md](docs/rfc/README.md) for the naming scheme and [docs/AGENTS.md](docs/AGENTS.md) for the cross-link convention.
**Markdown is not hard-wrapped**: write one line per paragraph and let the editor soft-wrap. Hard line breaks mid-paragraph make docs harder to edit and diff — a one-word change reflows and re-diffs the whole paragraph. This applies to prose only: leave fenced code blocks, tables, and list structure intact (a wrapped list item folds to one line per bullet). Code comments / JSDoc are exempt — they stay under the linter's column limit. `pnpm run verify-md-wrap` (part of `doc-sync`) enforces this across `README.md`, `docs/**/*.md`, `packages/*/*.md`, and `AGENTS.md` / `packages/AGENTS.md`; `pnpm run verify-md-links` (also part of `doc-sync`) checks that every relative cross-link in those files plus `examples/**/*.md` and `.agents/skills/**/*.md` resolves.
**Editing these instructions**: `AGENTS.md` is the real file; `CLAUDE.md` is a symlink to it (at the repo root and in `packages/` / `examples/`). Always edit `AGENTS.md` — never write through the `CLAUDE.md` symlink or replace it with a regular file.
## Vendoring Policy
`vendor/` packages are pinned source copies (manifest with upstream commit SHAs in [vendor/README.md](vendor/README.md)). To update one, follow the sync procedure there; re-apply (or retire) the logged local modifications and rerun `pnpm run test && pnpm run build`.
`vendor/` packages are pinned source copies (manifest with upstream SHAs in [vendor/README.md](vendor/README.md)). Update via the sync procedure there; re-apply or retire the logged local modifications; rerun `pnpm run test && pnpm run build`.

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# AGENTS.md — The documentation standard
This file is the contract for every Markdown surface in the repo: what each documentation tier is for, what belongs elsewhere, and the word budgets the `verify-doc-budgets` gate enforces. The repo-wide writing rules live in the root [AGENTS.md](../AGENTS.md) § "Type Safety and Documentation" and apply to everything here. The audit/apply workflow is the [dsh-doc-standards](../.agents/skills/dsh-doc-standards/SKILL.md) skill; the decision record is [the doc-tiers-and-budgets RFC](rfc/implemented/process/2026-07-04-doc-tiers-and-budgets.md).
This file is the contract for every Markdown surface in the repo: each tier's job, the writing rules, and the word budgets the `verify-doc-budgets` gate enforces. The audit/apply workflow is the [dsh-doc-standards](../.agents/skills/dsh-doc-standards/SKILL.md) skill; the decision record is [the doc-tiers-and-budgets RFC](rfc/implemented/process/2026-07-04-doc-tiers-and-budgets.md).
## The tier taxonomy: one home per fact
@@ -22,12 +22,22 @@ Every fact has exactly one home — the tier whose job it is — and every other
Placement test: a story about a bug → postmortem. Why we chose X → RFC. How to do task Y → cookbook. What type Z looks like → core-data-structures. What package P promises → its README. A rule every agent must always obey → root AGENTS.md, one line, linking the home that holds the why.
## Writing rules
- **Document the current state — never the process or history that produced it.** Prose describes what the code IS and why, as if it had always been so: no "previously/now/no longer/used to/renamed/moved here", and never name a change unit the reader cannot see — a PR, commit, or stack position — in comments, JSDoc, or test names; name the mechanism instead. A genuinely clarifying contrast is framed against the live alternative as a standing fact, not against the past. The change story belongs in the commit message, the PR description, or an RFC.
- **A decision worth re-litigating gets an RFC in the same PR.** The test: would a maintainer six months out ask "why was it done this way?" and find no answer in the code? If yes, write one ([when to write one](rfc/README.md)); mechanical or self-evident changes need none.
- **One physical line per paragraph** (`verify-md-wrap`): the editor soft-wraps; hard breaks make a one-word edit re-diff the whole paragraph. Prose only — code blocks, tables, and list structure stay; code comments stay under the linter's column limit.
- **Fenced `ts` blocks must compile** (`doc-typecheck`); a pasted type definition is fenced ` ```ts type-equiv ` and registered in the manifest so it cannot drift ([mechanics](development.md#documenting-types-verbatim-ts-type-equiv)).
- **Every new event's JSDoc carries an `@mode` tag** (emit | waterfall | parallel | serial); the catalog generator hard-errors without it. Write the JSDoc to stand alone — it becomes the catalog entry ([catalog RFC](rfc/implemented/process/2026-06-20-generated-cordis-catalog.md)).
- **The [core-data-structures catalog](core-data-structures/core.md) updates in the same change** that reshapes a documented type. `verify-type-equiv` catches drifted pastes, not never-documented new types ([what counts as core](core-data-structures/core.md#what-counts-as-core)).
- **Bilingual pairs update together**: editing either side obligates the counterpart and a re-record in the same change ([i18n contract](i18n/README.md)).
## Budgets and the ceiling gate
Standing docs accrete: every PR has a lesson it wants to append, and without displacement pressure nothing ever leaves. The gate is that pressure. [scripts/doc-budgets.manifest.json](../scripts/doc-budgets.manifest.json) lists the accretion-prone standing docs with a word ceiling each; `pnpm run verify-doc-budgets` (part of `doc-sync`, so CI and pre-push run it) fails when a doc exceeds its ceiling, and fails when a budgeted file is missing so a rename cannot orphan its budget.
- Ceilings are an enforcement frontier: a ceiling starts at the doc's current size (freezing further growth) and ratchets down as the doc is brought to its target. Target budgets: root `AGENTS.md` ≤ 1,500 words; `architecture.md` ≤ 1,800; each subtree `AGENTS.md` ≤ 600, except this file (which carries the standard) ≤ 1,000; `packages/README.md` ≤ 600.
- When the gate goes red, the fix is to relocate or condense per the taxonomy above. Raising a ceiling is the last resort: the PR description must justify it, and the manifest diff is the reviewable act.
- Ceilings are an enforcement frontier: a ceiling starts at the doc's current size (freezing further growth) and ratchets down as the doc is brought to its target. Target budgets: root `AGENTS.md` ≤ 1,500 words; `architecture.md` ≤ 1,800; each subtree `AGENTS.md` ≤ 600, except this file (which carries the standard) ≤ 1,250; `packages/README.md` ≤ 600.
- When the gate goes red, the fix is to relocate or condense per the taxonomy above. Raising a ceiling is the last resort: the PR must justify it; the manifest diff is the reviewable act.
- Unbudgeted tiers (package READMEs, RFCs, reference matrices) have no ceiling — length is legitimate there when every row is a fact. Review and the slop checklist govern them instead.
## The slop checklist

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# Responding to review across a stacked PR chain
A wave of review comments lands across several PRs in a dependent stack (`A ← B ← C …`). This is the discipline for resolving it without corrupting the stack. The two invariants it rests on are standing orders in the root [AGENTS.md](../../AGENTS.md) § Conventions: merge commits only, and never rewrite a pushed branch.
## Ground rules
1. **One worktree per PR branch.** Each PR's fixes happen in that PR's own worktree; parallel fixes never share a checkout.
2. **Bring a child up to date by merging the parent down** (`git merge <parent-branch>` into the child, a new merge commit). Never rebase/amend/force-push a pushed branch: rewriting diverges it from what the parent PR and GitHub recorded, breaks the stacked-merge graph, and erases the review-fix history.
3. **A fix lands on the PR that INTRODUCED the issue, then flows down.** When a comment on PR `B` points at code `B` introduced, fix it on `B` and merge `B` into `C` — even if `C` also carries the file. Originating the fix downstream leaves `B` shipping the unfixed code and hides the fix from `B`'s reviewer.
4. **Each review fix is a separate commit, never an amend.** The "fix review findings" commit documents what the review caught. Amending is fine only for your own not-yet-pushed, not-yet-reviewed work.
## Working the wave
1. Triage every comment on the merits before acting: verify the claim against the code — a reviewer flagging the right symptom can still mis-diagnose the cause.
2. Map each accepted finding to its originating PR, fix it there, then merge down the chain in order.
3. Delegated fixes are trust-but-verify: a sub-agent's report describes intent, not necessarily what landed. Re-run the gates yourself on the actual tree, and for a regression guard, prove it FAILS on the unfixed code (introduce the regression, watch red, revert) — a guard that passes both ways guards nothing. A sub-agent that reframes a problem as already-handled is a signal to dig in personally.
4. Reply in the review thread (`gh api repos/{owner}/{repo}/pulls/{pr}/comments/{id}/replies`), not as a top-level comment, stating the fix and the commit that carries it.
5. Before merging the stack, check dependents: deleting a PR's base branch auto-closes the dependent PR — `gh pr list --json number,baseRefName` first, and merge without `--delete-branch` where a child still bases on the branch.
## Verify
- Every fixed PR shows a new commit (no force-push icon in the PR timeline).
- Each child PR's diff against its parent still shows only its own changes.
- The gates pass on every PR in the stack, not just the top.

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# Defensive patterns
Hard-won bug-class rules: each pattern below is a class of defect that actually shipped or nearly shipped here, stated as the rule that prevents its recurrence. Read this before writing lifecycle, concurrency, subprocess, or teardown code. Test-tier counterparts (real entry path, world-verification, resource ownership) are in [testing.md](testing.md).
## Report orthogonal outcomes independently
A result can be several things at once — a process can time out AND exit 0 because it trapped the signal. Surface each independent fact (`timedOut`, `signal`, `exitCode`) on its own; never nest one flag's report inside another's branch, or a caller reads a cut-short run as a clean success.
## Honor cross-seam contracts on BOTH sides
When an interface documents two valid ways to signal something — an adapter may report failure by THROWING from `stream()` or by ending the stream with a `finish {kind:'error'|'aborted'}` chunk — the consumer handles both, not just the one the first implementation used. A library-backed adapter that can't throw mid-stream relies on the in-band path; a loop that only catches throws turns a provider 401 into a normal completed turn. Document the contract where the type is defined; exercise every branch through the real consumer.
## Async state is not synchronous state
`agent.send()` does not flip status before returning; a background task's completion races turn boundaries; `reader.close()` fires for both EOF and disposal. Never gate control flow on a status you only just requested — drive lifecycle off the events/promises that actually fire (`agent/status`, `task.done`), and observe the transition (saw `running` THEN `idle`) rather than counting actions you assume map 1:1 to turns (the loop batches queued messages). The guard cuts both ways: if the awaited transition can never occur (EOF with no work submitted → never `running`), the wait hangs — handle the "nothing to wait for" branch explicitly.
## Dispose must reach quiescence, not just request it
A teardown that issues kills/aborts but returns before the work stops leaves orphans. Make cleanup async and await the children's exit (kill → await `done`), and close listener/notification registries BEFORE killing so late completions stay silent. Tests prove disposal waited (pid gone right after `await fiber.dispose()`), not merely that the process eventually dies.
## Contain callback exceptions at the boundary
A user-supplied listener that throws must not reject the promise it runs inside or starve the listeners after it. Wrap the dispatch loop in try/catch and log; one bad subscriber never breaks core lifecycle.
## Never hand untrusted output the ambient environment or predictable paths
Spawned commands get a scrubbed env (drop `*KEY*`/`*SECRET*`/`*TOKEN*`) so harness credentials cannot leak into output, `env`, or spill files. Temp/spill files use a private (0700) dir, random names, and exclusive owner-only opens (`'wx'`, `0o600`) — predictable world-readable paths invite symlink races and disclosure.

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# RFCs
One kind of design doc lives here. An **RFC** records a decision or proposal that shapes this codebase — the *why* and *what we gave up*, the parts code and docs can't carry. (Earlier this split into separate "ADR" and "RFC" trees; they were unified, since most ADRs were simply implemented RFCs.)
One kind of design doc lives here. An **RFC** records a decision or proposal that shapes this codebase — the *why* and *what we gave up*, the parts code and docs can't carry.
## Layout and naming

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The hooks subsystem runs external hook commands the way Claude Code and Codex do: a hook is a shell command that receives its event payload as **JSON on stdin** and reads context from a handful of **environment variables** (`CLAUDE_PROJECT_DIR`, `CLAUDE_PLUGIN_ROOT`, `PLUGIN_ROOT`, …). The harness already has a perfectly good command runner behind the `ctx.bash` capability seam ([dsh-bash](../../../../packages/bash/bash) → [dsh-bash-local](../../../../packages/bash/bash-local)), with process-group kills, output truncation/spill, and a credential scrub. Reusing it for hook execution means a hook bridge does not re-implement subprocess plumbing — but the seam had no way to write stdin or set extra env. This RFC adds those two inputs.
**These fields are NOT a new security boundary.** It is tempting to frame arbitrary-stdin / arbitrary-env as "dangerous, so gate who may use them" — but that framing is wrong, because a model driving the `bash` tool **already** has equivalent power through ordinary shell syntax: `FOO=bar cmd` sets an env var, a heredoc or `printf … | cmd` feeds arbitrary stdin. Adding `env`/`stdin` as seam fields grants the model no capability it lacks. In particular they cannot exfiltrate the harness's ambient credentials: the real control for that is the **credential scrub** in [dsh-bash-local](../../../../packages/bash/bash-local)'s `childEnv()`, which strips `*KEY*`/`*SECRET*`/`*TOKEN*` from `process.env` before the child sees it (see [AGENTS.md](../../../../AGENTS.md) § Defensive patterns, "Never hand untrusted/model output the ambient environment or predictable paths"). The scrub works regardless of these fields — a model cannot read a value that is not in the environment, and tool-call arguments are static JSON, never shell-evaluated, so a model cannot write `env: {LEAK: $DEEPSEEK_API_KEY}` and have it expand. So the security question is already answered by the scrub; this RFC is only about giving trusted in-process callers a clean way to pass a JSON payload + `CLAUDE_*` vars without routing them through model-visible shell text.
**These fields are NOT a new security boundary.** It is tempting to frame arbitrary-stdin / arbitrary-env as "dangerous, so gate who may use them" — but that framing is wrong, because a model driving the `bash` tool **already** has equivalent power through ordinary shell syntax: `FOO=bar cmd` sets an env var, a heredoc or `printf … | cmd` feeds arbitrary stdin. Adding `env`/`stdin` as seam fields grants the model no capability it lacks. In particular they cannot exfiltrate the harness's ambient credentials: the real control for that is the **credential scrub** in [dsh-bash-local](../../../../packages/bash/bash-local)'s `childEnv()`, which strips `*KEY*`/`*SECRET*`/`*TOKEN*` from `process.env` before the child sees it (see [docs/defensive-patterns.md](../../../defensive-patterns.md) § "Never hand untrusted output the ambient environment or predictable paths"). The scrub works regardless of these fields — a model cannot read a value that is not in the environment, and tool-call arguments are static JSON, never shell-evaluated, so a model cannot write `env: {LEAK: $DEEPSEEK_API_KEY}` and have it expand. So the security question is already answered by the scrub; this RFC is only about giving trusted in-process callers a clean way to pass a JSON payload + `CLAUDE_*` vars without routing them through model-visible shell text.
## Decision

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## Decision
- **A tier taxonomy with one home per fact.** [docs/AGENTS.md](../../../AGENTS.md) is the documentation standard: it assigns every Markdown tier a single job (standing orders, system map, type catalog, decision records, incident stories, how-tos, per-package contracts, generated catalogs, workflows), forbids restating a fact outside its home tier (link instead), and carries the slop checklist used when writing or reviewing any doc.
- **A narrow, hard budget gate.** [scripts/verify-doc-budgets.ts](../../../../scripts/verify-doc-budgets.ts) joins `doc-sync`: every doc listed in [scripts/doc-budgets.manifest.json](../../../../scripts/doc-budgets.manifest.json) must stay under its word ceiling (`wc -w` semantics, whole file), and a budgeted file that is missing fails the gate so a rename cannot silently orphan its budget. Scope is deliberately only the accretion-prone standing docs — the root and subtree `AGENTS.md` files, `architecture.md`, `packages/README.md`. Reference docs, RFCs, and package READMEs are unbudgeted: length is legitimate there when every row is a fact, and review plus the slop checklist govern them.
- **A narrow, hard budget gate.** [scripts/verify-doc-budgets.ts](../../../../scripts/verify-doc-budgets.ts) joins `doc-sync`: every doc listed in [scripts/doc-budgets.manifest.json](../../../../scripts/doc-budgets.manifest.json) must stay under its word ceiling (`wc -w` semantics, whole file), and a budgeted file that is missing fails the gate so a rename cannot silently orphan its budget. Scope is deliberately only the accretion-prone standing docs — the root and subtree `AGENTS.md` files, `architecture.md`, `packages/README.md`, and the standing policy docs they evict content into (`docs/testing.md`, `docs/defensive-patterns.md`). Reference docs, RFCs, and package READMEs are unbudgeted: length is legitimate there when every row is a fact, and review plus the slop checklist govern them.
- **Ceilings are an enforcement frontier that ratchets.** A ceiling starts at the doc's current size, freezing growth from day one, and ratchets down as the doc is brought to its target budget (root `AGENTS.md` ≤ 1,500 words; `architecture.md` ≤ 1,800; subtree `AGENTS.md` ≤ 600; `packages/README.md` ≤ 600) — the same rollout mechanism as the [translation-pairing `required` list](2026-07-02-bilingual-docs-and-pairing-gate.md). When the gate goes red the fix is to relocate or condense per the taxonomy; raising a ceiling is permitted only with explicit justification in the PR description, the manifest diff being the reviewable act.
- **A thin workflow skill, contracts in docs.** [.agents/skills/dsh-doc-standards](../../../../.agents/skills/dsh-doc-standards/SKILL.md) carries the placement/audit/red-gate workflow and defers to the standard as its source of truth, the same split as [dsh-translate-docs](../../../../.agents/skills/dsh-translate-docs/SKILL.md) over the i18n contract.
@@ -27,9 +27,7 @@ The repo's standing docs accrete. Root `AGENTS.md` reached 8,130 words through 5
The first audit cycle under the standard, in rough priority order (evidence gathered in the survey that motivated this RFC):
- Root `AGENTS.md` rewrite to the ≤ 1,500-word target: rules stay as one-liners plus links; situational clusters move to `docs/testing.md`, `docs/defensive-patterns.md`, and a cookbook guide for responding to review across a stacked PR chain; doc-authoring rules consolidate into `docs/AGENTS.md`.
- `architecture.md` rewrite to the ≤ 1,800-word target: seam narration compressed to pointers, the MVP feature-to-mechanism checklist moved de-statused into [the extension cookbook](../../../cookbook/extension-cookbook.md), the stale layering-diagram row fixed.
- `packages/README.md` reduced to the group table plus the dependency rule; the hand-maintained ASCII dependency graph yields to the generated [module-graph.md](../../../module-graph.md); group READMEs become the canonical per-package map.
- Package README trims where generated catalogs or JSDoc are restated or history is narrated: `packages/ui/acp`, `packages/core/tools`, `packages/bash/tool-bash`, `packages/core/session`, `packages/compact/compact-basic`, `packages/session-persistence/session-persistence`.
- [The web capability seam RFC](../architecture/2026-06-24-web-capability-seam.md) converted from spec-speak to shipped reality (drop the migration plan and test enumeration, "should" → "is").
- `docs/core-data-structures/core.md`: drop the JSDoc walls from the `Agent`/`GenerateOptions` type-equiv pastes per that page's own stated rule.

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Status: implemented (proposed 2026-06-20; accepted in amended form — `whenIdle()` retained)
> **Implementation note (scope narrowed from the original proposal).** This RFC proposed removing BOTH `abort()` and `whenIdle()` from the public `Agent` handle. Only `abort()` was removed. Validating the premise against the code ([AGENTS.md "RFCs are proposals, not golden truth"](../../../../AGENTS.md)) found `whenIdle()` to be a **load-bearing quiescence primitive**, not dead surface: it is the settle signal in several ACP tests (`packages/ui/acp/tests/{edges,turns,dispose}.spec.ts`) and is backed by a deliberate loop contract (settle waiters without a status transition; handle the replacement-turn race). The RFC's suggested migration — have consumers observe the `running`→`idle` transition by hand — is exactly the brittle hand-rolled path [AGENTS.md § Defensive patterns](../../../../AGENTS.md) warns against ("Async state is not synchronous state"). Deleting a clean primitive to push every consumer onto that is a net loss, so `whenIdle()` stays. `abort()` was genuinely dead public surface (no production caller; the loop aborts its own `AbortController` directly), so it was removed as proposed. The text below is amended to describe what shipped.
> **Implementation note (scope narrowed from the original proposal).** This RFC proposed removing BOTH `abort()` and `whenIdle()` from the public `Agent` handle. Only `abort()` was removed. Validating the premise against the code ([AGENTS.md "RFCs are proposals, not golden truth"](../../../../AGENTS.md)) found `whenIdle()` to be a **load-bearing quiescence primitive**, not dead surface: it is the settle signal in several ACP tests (`packages/ui/acp/tests/{edges,turns,dispose}.spec.ts`) and is backed by a deliberate loop contract (settle waiters without a status transition; handle the replacement-turn race). The RFC's suggested migration — have consumers observe the `running`→`idle` transition by hand — is exactly the brittle hand-rolled path [the defensive patterns](../../../defensive-patterns.md) warns against ("Async state is not synchronous state"). Deleting a clean primitive to push every consumer onto that is a net loss, so `whenIdle()` stays. `abort()` was genuinely dead public surface (no production caller; the loop aborts its own `AbortController` directly), so it was removed as proposed. The text below is amended to describe what shipped.
## Problem

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# Testing policy
How this repo tests, tier by tier, and the rules that keep a green suite meaning something. Commands live in the root [AGENTS.md](../AGENTS.md) § Commands; the RFCs linked per tier carry the design rationale.
## Tiers
- **Unit** (`pnpm run test`): vitest, colocated at `packages/<group>/<pkg>/tests/*.spec.ts`. Every registry gets an HMR-safety test (dispose the contributing fiber, assert cleanup). Excessive tests are welcome — err toward covering edge cases, error paths, event ordering, and concurrency races; review findings get regression tests (see `packages/core/agent-loop/tests/review-fixes.spec.ts`).
- **Coverage gate** (`pnpm run test:coverage`): the gating run, per-file 100% on `packages/*/*/src`. An uncovered line is often dead code the gate is correctly flagging for deletion, not a missing test to bolt on. Line coverage is necessary, never sufficient — it proves lines ran, not that the feature works as shipped.
- **Real-API e2e** (`pnpm run test:e2e`): with-key tests against the live DeepSeek API; self-skip without `DEEPSEEK_API_KEY` so keyless CI stays green ([real-API e2e RFC](rfc/implemented/testing/2026-06-19-real-api-e2e-ci.md)).
- **Snapshot** (`pnpm run test:snapshot`): boots the real example subprocess, replays a recorded session keyless, diffs normalized stdout + the re-persisted log against committed goldens ([snapshot RFC](rfc/implemented/testing/2026-06-19-acp-snapshot-tests.md)). Re-record with `pnpm run test:snapshot:record`; reviewing the golden diff is part of the review.
## The with-key policy: inference is cheap here
We are DeepSeek — do not ration real-API tests. A no-key test proves the plumbing; only a with-key run proves the agent works against a real model. Write many: real prompts that write files, multi-turn conversations, tool use, cancellation mid-stream. Cheapest and highest-value are **smoke tests** that boot the real example, send one real prompt, and check the world — they catch the "green unit tests, broken product" class that mocks structurally cannot ([postmortem 0001](postmortem/0001-acp-default-export-drops-inject.md)). The self-skip exists only so secretless CI and keyless contributors aren't blocked; it is not a cost signal. Every example ships both a keyless and a with-key smoke ([examples/AGENTS.md](../examples/AGENTS.md)).
## Prefer the real implementation over a mock
Mock only the genuinely expensive or non-deterministic boundary (the LLM adapter, the network, the clock); keep everything downstream real. A hand-rolled stand-in proves the bridge moves bytes, not that the shipping tool behaves as asserted — the two drift while the test stays green. Example: bridge tool-call tests run the scripted mock MODEL but the real tool + real executor (`makeBridgeHarness({ withBash: true })` plugs `dsh-bash-local` + `dsh-tool-bash` and runs an actual `echo`).
## Verify the world, not the self-report
An e2e assertion re-runs the command or re-reads the file externally; a keyword probe on the agent's own output lets a cheating agent pass. Assert untouched files are byte-identical. e2e tests own their resources: create the harness in the test, dispose in `afterEach` (even on failure/retry/timeout); shared fixtures live in a plain `tests/harness.ts`, never another `*.e2e.ts` (importing a spec re-registers its `describe` and duplicates real API calls).
## Test the real entry path
- A plugin shipped via `cordis.yml` needs at least one test through the REAL Loader path: hand-built `ctx.plugin({...})` mounts bypass `unwrapExports` and cannot catch a broken export shape ([postmortem 0001](postmortem/0001-acp-default-export-drops-inject.md); export-shape rules in [packages/AGENTS.md](../packages/AGENTS.md)).
- A guard only guards if the regression actually fails it. For a plugin without `inject` (bundle/composition plugins), a Loader smoke stays green under a broken export shape — add an explicit `expect('default' in mod).toBe(false)` plus an `unwrapExports` round-trip assertion, and prove it: introduce the regression, watch red, revert.
- "Real entry path" means the published artifact: the package `bin` points at built `lib/bin.js` under plain `node`, which tsx masks (settle races, module resolution, a swallowed load failure exiting 0). Keep the built-bin smokes green (`packages/ui/*/tests/built-bin.e2e.ts`), and assert a genuinely-missing config exits non-zero.
- An e2e that spawns an example from a temp cwd sets `TSX_TSCONFIG_PATH` to the repo-root tsconfig, or it silently falls back to stale built `lib/` ([examples/AGENTS.md](../examples/AGENTS.md)).
## When a snapshot test is required
Any change affecting the editor-facing transcript or end-to-end agent UX — the ACP bridge, the loop's observable output, tool presentation — adds or updates a scenario under `examples/acp-agent/tests/snapshots/` (or states in the PR why none applies). New capability seams, lifecycle shapes, or transcript surfaces name their coverage at every tier at plan time and verify the harness can express it — a harness gap is scheduled work, not a mid-build surprise.

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Each example must have **both** kinds of end-to-end smoke, because they catch different failures:
- **Keyless smoke** — boot the example through its real `cordis.yml` via the Loader (no API key), drive it, and assert the rendered output and a clean exit. This is the guard a hand-mounted unit test structurally cannot be: it exercises the REAL load path (`unwrapExports`, `inject`, the whole plugin tree), so a broken plugin export shape — e.g. a stray `export default` that collapses a namespace plugin and drops `inject` — fails here even when unit tests stay green (see [docs/postmortem/0001](../docs/postmortem/0001-acp-default-export-drops-inject.md)). It runs in the default e2e gate (CI has no secrets).
- **With-key smoke** — send a real prompt against the live model and verify the WORLD (a file on disk, a non-empty assistant turn), not the agent's self-report. This proves the actual product works, which a mock/keyless run structurally cannot. Key-gated: it self-skips without `DEEPSEEK_API_KEY` (see [the with-key policy](../AGENTS.md#secrets--env) — inference is cheap here, so write many).
- **With-key smoke** — send a real prompt against the live model and verify the WORLD (a file on disk, a non-empty assistant turn), not the agent's self-report. This proves the actual product works, which a mock/keyless run structurally cannot. Key-gated: it self-skips without `DEEPSEEK_API_KEY` (see [the testing policy](../docs/testing.md) — inference is cheap here, so write many).
**Exception — keyless-by-nature examples.** An example whose model is itself a mock/deterministic stand-in (no real provider) has no meaningful with-key smoke; the keyless smoke is the complete requirement. State the exception inline in the test.

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# AGENTS.md — Harness Packages
This directory contains all `@deepseek-ai/dsh-*` harness packages. When editing code here, follow these conventions:
This directory contains all `@deepseek-ai/dsh-*` harness packages. Repo-wide conventions (effects, declaration merging, waterfall semantics, ESM, testing policy) are in the root [AGENTS.md](../AGENTS.md) § Conventions; the points below are packages-specific.
- **Effect-based registrations**: every contribution (tool, section, adapter, agent, event listener) goes through `ctx.effect()` / `ctx.on()`, and `register()` methods return disposers. Never use bare arrays or manual cleanup.
- **Declaration merging**: services declare their ctx key in `declare module 'cordis' { interface Context { } }` and their events in `interface Events`. Merge-extensible maps (`ContentBlockMap`, `MessageSourceMap`, `FinishReasonMap`, `TurnTriggerMap`, `TurnEndReasonMap`, `SessionEventMap`) are how plugins add new variants.
- **Waterfall semantics**: `ctx.waterfall` listeners receive `(...args, next)`; call `next()` to delegate, or return without it to short-circuit (veto). Never call `next()` after returning.
- **Plugin export shape — namespace OR default, never both.** A *service* package exports the service class as `export default` (the Loader instantiates it). A *function/namespace* plugin exports `name` / `inject` / `Config` / `apply` as separate named exports and **must NOT add `export default`** — the cordis Loader's `unwrapExports` does `exports.default ?? exports`, so a stray default export collapses the module to the bare `apply` function and silently discards the `inject`/`name`/`Config` namespace, leaving the plugin with no injected services (it then throws `cannot get property … without inject` at load). See [docs/postmortem/0001](../docs/postmortem/0001-acp-default-export-drops-inject.md).
- **Read an optional (non-injected) service via `ctx.get(name)`, not `ctx.<name>`.** For a service a plugin reads opportunistically but deliberately leaves out of `static inject` (e.g. `AgentLoop` reading `sessionPersistence`), the `ctx.<name>` property proxy resolves by an ancestor-only fiber walk that throws when the call arrives through a foreign traceable shadow (the service lives on a sibling fiber). `ctx.get(name)` is the topology-independent global-store lookup, strict by default (an inactive/absent backend reads as `undefined` — prefer it over the `ctx.get(name, false)` overload, which also skips the active-state check). Services that ARE in `static inject` resolve fine via `ctx.<name>`. See [docs/postmortem/0001](../docs/postmortem/0001-acp-default-export-drops-inject.md).
- **Tests**: vitest in `packages/<group>/<pkg>/tests/*.spec.ts`. Every registry needs an HMR-safety test (register a plugin, dispose its fiber, assert cleanup). Err on the side of more tests — edge cases, error paths, event ordering, races. A plugin shipped via `cordis.yml` also needs at least one test that drives it through the REAL Loader/export path (hand-built `ctx.plugin({...})` mounts bypass `unwrapExports` and cannot catch a broken export shape) — see AGENTS.md § Defensive patterns "Line coverage is not behavior coverage". Real-API (with-key) e2e tests are cheap here (we are DeepSeek) and welcome — write many, especially smoke tests; see AGENTS.md § Secrets / .env.
- **A plugin shipped via `cordis.yml` needs at least one test through the REAL Loader/export path** — hand-built `ctx.plugin({...})` mounts bypass `unwrapExports` and cannot catch a broken export shape. Full testing policy (tiers, with-key generosity, real-entry-path guards): [docs/testing.md](../docs/testing.md).
Naming notes:
- A *service* `src/index.ts` exports the service class as `export default` + all public types; a *function/namespace plugin* `src/index.ts` exports `name`/`inject`/`Config`/`apply` as named exports and NO default (see the plugin-export-shape rule above)
- `src/types.ts` contain only types — no runtime code
- Tests live at package level under `tests/`, not `src/__tests__/`
- A package's README and module/JSDoc comments are part of the change: when you alter behavior (config keys, defaults, error codes, wire fields), update them in the same commit. CI runs `pnpm run doc-sync`, which typechecks fenced `ts` blocks in `packages/*/*.md` and `packages/*/*/*.md`, regenerates the cordis events/services catalog from the `interface Events` / `interface Context` declarations (failing if the committed copy is stale), and checks markdown wrapping across this file too — but it does NOT catch prose drift (config keys, defaults, error codes), so those stay on the author. A new event needs an `@mode` tag on its JSDoc (the catalog generator hard-errors without it — see the root AGENTS.md).
- A *service* `src/index.ts` exports the service class as `export default` + all public types; a *function/namespace plugin* `src/index.ts` exports `name`/`inject`/`Config`/`apply` as named exports and NO default (the export-shape rule above).
- `src/types.ts` contains only types — no runtime code.
- Tests live at package level under `tests/`, not `src/__tests__/`.
- A package's README and JSDoc are part of the change: altered behavior (config keys, defaults, error codes, wire fields) updates them in the same commit. `doc-sync` gates what it can; prose accuracy stays on the author ([the documentation standard](../docs/AGENTS.md)).
Read the per-package README.md for package-specific details: service API, events, extension points, TODOs.

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# Packages
Harness packages, all under the `@deepseek-ai/dsh-*` scope. Each package is a Cordis plugin (microkernel-style): it exports either a default `Service` subclass or a functional plugin that gets registered via `ctx.plugin()`, declares its ctx key/events where applicable through declaration merging, and exposes extension points through `ctx.effect()`, `ctx.on()`, and `ctx.waterfall()`.
Harness packages, all under the `@deepseek-ai/dsh-*` scope. Each package is a Cordis plugin (microkernel-style): it exports either a default `Service` subclass or a functional plugin, declares its ctx key/events through declaration merging, and exposes extension points through `ctx.effect()`, `ctx.on()`, and `ctx.waterfall()`. Authoring conventions: [AGENTS.md](AGENTS.md) (subtree) and the root [AGENTS.md](../AGENTS.md) § Conventions.
## Hierarchy
Packages are grouped by modular role at `packages/<group>/<pkg>/`. The group directory is a pure container (no `package.json` of its own); the package name stays `@deepseek-ai/dsh-<pkg>` regardless of group. Each group has a `README.md` describing its role and whether it is product or support infrastructure.
Packages are grouped by modular role at `packages/<group>/<pkg>/`. The group directory is a pure container (no `package.json` of its own); the package name stays `@deepseek-ai/dsh-<pkg>` regardless of group. **Each group README is the canonical per-package map** — package roles, ctx keys, and the product-vs-support split live there, next to the code.
| Group | Role | Release expectation |
|---|---|---|
@@ -18,115 +18,16 @@ Packages are grouped by modular role at `packages/<group>/<pkg>/`. The group dir
| [`todo/`](todo/README.md) | Todo/planning family: the model-facing `todo_write` tool (whole-list task tracking on the session log) | Product — stable surface |
| [`hooks/`](hooks/README.md) | Hook bridges + the shared Claude Code / Codex wire-protocol library | Product — stable surface |
| [`session-persistence/`](session-persistence/README.md) | Persistence capability family: the seam + JSONL/SQLite backends | Product — stable surface |
| [`ui/`](ui/README.md) | Editor/client integration surfaces (the ACP bridge) | Product — stable surface |
| [`ui/`](ui/README.md) | Editor/client integration surfaces (the ACP bridge) + the app packages | Product — stable surface |
| [`support/`](support/README.md) | Dev/test/example infrastructure (invariants, stdio UI, replay adapter) | Support — lower compatibility expectations |
| [`util/`](util/README.md) | Low-level zero-dependency utilities shared across groups (the `Branded<B>` primitive) | Support — small, stable, harness-dep-free |
The split is the point: a package's group says whether it is part of the product API or support/test/example infrastructure, so release and removal decisions do not have to treat every package as an equal public contract. New packages join an existing group; adding a new top-level group is a deliberate act (extend the group READMEs and the hierarchy docs).
The split is the point: a package's group says whether it is part of the product API or support/test/example infrastructure, so release and removal decisions do not treat every package as an equal public contract. New packages join an existing group; adding a new top-level group is a deliberate act (extend the group READMEs and this table).
## Dependency graph
## Dependencies
```
dsh-brand (no harness deps — type-only Branded<B> primitive)
dsh-llm ← dsh-brand (vocabulary; brands CallId)
dsh-bash ← dsh-brand (abstract executor seam; brands BashTaskId/OwnerToken)
dsh-session ← dsh-llm, dsh-brand
dsh-system-prompt ← dsh-llm
dsh-agent ← dsh-llm, dsh-session, dsh-brand
dsh-compact ← dsh-session, dsh-llm (abstract compaction seam; tool deferred)
dsh-compact-basic ← dsh-compact, dsh-session, dsh-llm, dsh-agent (char/4 + token-budget retention backend)
dsh-tools ← dsh-llm, dsh-system-prompt, dsh-agent
dsh-bash-local ← dsh-bash (BashExecutor impl)
dsh-tool-bash ← dsh-bash, dsh-tools (bash tool schemas)
dsh-fs ← dsh-llm, dsh-brand (filesystem provider seam + fs/* events)
dsh-fs-local ← dsh-fs (FileSystem impl)
dsh-fs-policy ← dsh-fs (observed-state + freshness policy gate, no service)
dsh-tool-fs ← dsh-fs, dsh-tools (file tools + executor)
dsh-web ← dsh-llm (abstract web seam; search/fetch registries, WebError)
dsh-web-search-exa ← dsh-web (Exa WebSearchProvider)
dsh-web-search-perplexity ← dsh-web (Perplexity WebSearchProvider)
dsh-web-search-deepseek ← dsh-web (DeepSeek native-web-search WebSearchProvider)
dsh-web-fetch-local ← dsh-web (anonymous public HTTP(S) WebFetchProvider)
dsh-tool-web ← dsh-web, dsh-tools, dsh-system-prompt (web tool schemas)
dsh-llm-deepseek ← dsh-llm (DeepSeek adapter)
dsh-llm-pi-ai ← dsh-llm (pi-ai-backed adapter)
dsh-agent-loop ← dsh-llm, dsh-session, dsh-session-persistence, dsh-system-prompt, dsh-tools, dsh-agent
dsh-invariants ← dsh-llm, dsh-session, dsh-agent (dev-mode contract checks)
dsh-acp ← dsh-agent, dsh-llm, dsh-session, dsh-session-persistence, dsh-tools (ACP JSON-RPC bridge)
dsh-ui-stdio ← dsh-agent, dsh-llm, dsh-session (stdio readline UI plugin)
dsh-llm-replay ← dsh-llm, dsh-session (record/replay adapter for keyless snapshot tests)
dsh-subagent ← dsh-agent, dsh-llm, dsh-tools (abstract subagent provider-registry seam)
dsh-subagent-inprocess ← dsh-subagent, dsh-agent, dsh-session, dsh-llm (shared in-process run driver)
dsh-subagent-mock ← dsh-subagent, dsh-agent, dsh-llm (scripted provider for tests)
dsh-subagent-spawn ← dsh-subagent, dsh-subagent-inprocess (in-process fresh child backend)
dsh-subagent-fork ← dsh-subagent, dsh-subagent-inprocess, dsh-agent, dsh-session (in-process child seeded from parent log)
dsh-subagent-acp ← dsh-subagent, dsh-agent, dsh-llm, @agentclientprotocol/sdk (out-of-process child over ACP)
dsh-tool-subagent ← dsh-subagent, dsh-tools, dsh-agent, dsh-llm (model-facing delegation tool)
dsh-tool-todo ← dsh-tools, dsh-agent, dsh-session (model-facing todo_write tool; whole list on the session log)
dsh-agent-core ← timer, dsh-llm, dsh-session, dsh-system-prompt, dsh-tools, dsh-agent, dsh-invariants, dsh-tool-bash, dsh-agent-loop (the providerless spine, as one bundle plugin)
dsh-stdio-agent ← dsh-agent-core, dsh-ui-stdio, dsh-session-persistence-jsonl, dsh-agent, dsh-session (stdio chat APP + bin)
dsh-acp-agent ← dsh-agent-core, dsh-acp, dsh-session-persistence-jsonl (ACP server APP + bin)
```
The inter-package dependency graph is generated: [docs/module-graph.md](../docs/module-graph.md) (`pnpm run gen-module-graph`, freshness-gated in CI).
The rule: **extension** plugins depend on interfaces, never on the concrete loop. `dsh-agent-loop` is swappable — UI/hook/tool plugins keep working against the `dsh-agent` vocabulary if the loop is replaced. The sanctioned exception is a **composition/bundle** package like `dsh-agent-core`, whose whole job is to assemble the concrete spine: it depends on `dsh-agent-loop` (and the other concrete spine plugins) on purpose. The rule constrains plugins that EXTEND the system, not the bundle that COMPOSES it — swapping the loop means shipping a different bundle, not rewiring every extension. A swappable capability splits into interface / implementation / consumer packages (the bash trio is the template — see [capability seams](../docs/rfc/implemented/architecture/2026-06-13-capability-seams.md)).
## What goes where
| Package | Group | Role | ctx key |
|---|---|---|---|
| `llm/` | `llm` | Abstract LLM service + content-block vocabulary + chunk assembler | `ctx.llm` |
| `session/` | `core` | Event-sourced session log + in-memory store | `ctx.sessions` |
| `system-prompt/` | `core` | Prompt-section + tool-schema assembly registry | `ctx.systemPrompt` |
| `tools/` | `core` | Tool registry + `tools/pre-execute`/`tools/post-execute` pipeline | `ctx.tools` |
| `agent/` | `core` | Agent interface, registry, `agent/*` event vocabulary | `ctx.agents` |
| `agent-loop/` | `core` | THE concrete loop plugin: `ReactLoopAgent` + the loop driver | `ctx.agentLoop` |
| `agent-core/` | `core` | Bundle plugin: the providerless/executor-less/UI-less spine as code (forwards `agent-loop`'s `agents`) | (loads the spine) |
| `bash/` | `bash` | Abstract bash executor seam (interface + vocabulary) | `ctx.bash` |
| `bash-local/` | `bash` | Local-subprocess `BashExecutor` implementation | (registers `ctx.bash`) |
| `tool-bash/` | `bash` | Model-facing `bash`/`bash_output`/`bash_kill` tool schemas | (registers on `ctx.tools`) |
| `fs/` | `fs` | Filesystem provider seam: text IO + atomic mutation primitives (optional version guard); owns the `fs/*` events | `ctx.fs` |
| `fs-local/` | `fs` | Local-filesystem `FileSystem` implementation | (registers `ctx.fs`) |
| `fs-policy/` | `fs` | Policy gate plugin: observed-state + read-before-edit + version-guarded write/edit via the `fs/*` event gate | (no service — `fs/*` listeners) |
| `tool-fs/` | `fs` | Model-facing `read`/`write`/`edit` tools + executor (reads via `ctx.fs`, owns read windowing, dispatches `fs/*`) | (registers on `ctx.tools`) |
| `compact/` | `compact` | Abstract compaction seam + `compact/*` events + `CompactionResult` | `ctx.compact` |
| `compact-basic/` | `compact` | A backend: char/4 estimation + token-budget retention + `llm.stream()` summarization | (registers `ctx.compact`) |
| `web/` | `web` | Abstract web seam (search/fetch provider registries + selection + vocabulary + `WebError`) | `ctx.web` |
| `web-search-exa/` | `web` | Exa-backed `WebSearchProvider` | (registers on `ctx.web`) |
| `web-search-perplexity/` | `web` | Perplexity-backed `WebSearchProvider` | (registers on `ctx.web`) |
| `web-search-deepseek/` | `web` | DeepSeek-backed `WebSearchProvider` using native `web_search` through the Anthropic-compatible API | (registers on `ctx.web`) |
| `web-fetch-local/` | `web` | Anonymous public HTTP(S) `WebFetchProvider` | (registers on `ctx.web`) |
| `tool-web/` | `web` | Model-facing `web_search`/`web_fetch` tool schemas | (registers on `ctx.tools`) |
| `llm-deepseek/` | `llm` | DeepSeek API adapter (hand-rolled fetch/SSE) | (registers on `ctx.llm`) |
| `llm-pi-ai/` | `llm` | DeepSeek adapter via `@earendil-works/pi-ai` (design twin) | (registers on `ctx.llm`) |
| `session-persistence/` | `session-persistence` | Persistence seam + write coordinator | `ctx.sessionPersistence` |
| `session-persistence-jsonl/` | `session-persistence` | JSONL-sidecar persistence backend | (registers `ctx.sessionPersistence`) |
| `session-persistence-sqlite/` | `session-persistence` | SQLite persistence backend | (registers `ctx.sessionPersistence`) |
| `invariants/` | `support` | Dev-mode event-contract invariants + session-log freeze | (listens on `session/*`, `agent/*`) |
| `acp/` | `ui` | Agent Client Protocol bridge: serves the agent to an ACP editor over JSON-RPC stdio | (drives `ctx.agents`/`ctx.sessions`) |
| `stdio-agent/` | `ui` | Terminal stdio chat APP: agent-core spine + console logger + readline UI + a pre-created `main` agent, with a `bin` | (composition + `bin`) |
| `acp-agent/` | `ui` | ACP server APP: agent-core spine + JSONL persistence + the `acp` bridge (no stdout logger), with a `bin` | (composition + `bin`) |
| `ui-stdio/` | `support` | Minimal stdio (readline) UI plugin: renders `agent/*` events, feeds stdin lines to the agent | (drives `ctx.agents`) |
| `llm-replay/` | `support` | Record/replay adapter: short-circuits `llm/stream` with chunks from a recorded session JSONL (keyless snapshot tests) | (listens on `llm/stream`) |
| `subagent/` | `subagent` | Abstract subagent seam: named-provider registry for delegating to child agents | `ctx.subagents` |
| `subagent-inprocess/` | `subagent` | Shared in-process subagent run driver used by spawn/fork; pure library, registers nothing | (none) |
| `subagent-spawn/` | `subagent` | In-process backend: a fresh child agent | (registers on `ctx.subagents`) |
| `subagent-fork/` | `subagent` | In-process backend: a child agent seeded with the parent's completed-turn prefix | (registers on `ctx.subagents`) |
| `subagent-acp/` | `subagent` | Out-of-process backend: a child agent in a spawned subprocess, driven over the Agent Client Protocol | (registers on `ctx.subagents`) |
| `subagent-mock/` | `support` | Scripted `SubagentProvider` for testing the seam through the real load path | (registers on `ctx.subagents`) |
| `tool-subagent/` | `subagent` | Model-facing `subagent` delegation tool over `ctx.subagents` | (registers on `ctx.tools`) |
| `tool-todo/` | `todo` | Model-facing `todo_write` tool; writes the whole task list to the session log (`todo/write`) | (registers on `ctx.tools`) |
| `hook-protocol/` | `hooks` | Shared Claude Code / Codex hook wire-protocol library: matcher, codec, `runHook`, merge, `hook/*` events | (none — library, no service) |
| `hooks-claude/` | `hooks` | Bridge: runs a Claude Code `hooks.json` / settings on the interception seams | (registers event listeners) |
| `hooks-codex/` | `hooks` | Bridge: runs a Codex `hooks.json` (a subset of the CC protocol) on the seams | (registers event listeners) |
| `brand/` | `util` | Type-only `Branded<B>` nominal-typing primitive (no runtime code, no harness deps) | (none — type-only) |
The rule it must obey: **extension plugins depend on interfaces, never on the concrete loop.** `dsh-agent-loop` is swappable — UI/hook/tool plugins keep working against the `dsh-agent` vocabulary if the loop is replaced. The sanctioned exception is a **composition/bundle** package like `dsh-agent-core`, whose whole job is to assemble the concrete spine: it depends on `dsh-agent-loop` (and the other concrete spine plugins) on purpose. The rule constrains plugins that EXTEND the system, not the bundle that COMPOSES it — swapping the loop means shipping a different bundle, not rewiring every extension. A swappable capability splits into interface / implementation / consumer packages (the bash trio is the template — see [capability seams](../docs/rfc/implemented/architecture/2026-06-13-capability-seams.md)).
Each package has its own `README.md` with purpose, service API, events, extension points, and deliberate non-goals (TODOs).
## Conventions (applied across all harness packages)
- **Registrations are effects**: every contribution (adapter, tool, section, agent, event listener) goes through `ctx.effect()` / `ctx.on()`, so disposal and HMR clean up automatically. Every `register()` returns the disposer.
- **Declaration merging for events and ctx**: services declare their events in `declare module 'cordis' { interface Events { ... } }` and their ctx key in `interface Context`.
- **Waterfall semantics**: `ctx.waterfall` listeners receive `(...args, next)` and MUST call `next()` to delegate; returning without it short-circuits (the veto mechanism).
- **Extensible unions**: `ContentBlockMap`, `MessageSourceMap`, `FinishReasonMap`, `TurnTriggerMap`, `TurnEndReasonMap`, and `SessionEventMap` use the merge-extensible-map pattern so plugins can add variants via declaration merging.
- **ESM everywhere**; imports use package names across package boundaries and explicit `.ts` relative specifiers within a package.
- **Tests**: vitest, colocated under `packages/<group>/<pkg>/tests/*.spec.ts`. Every registry needs an HMR-safety test. Err on the side of more tests.

10
scripts/doc-budgets.manifest.json
View File

@@ -1,8 +1,10 @@
{
"AGENTS.md": 8200,
"docs/AGENTS.md": 1000,
"AGENTS.md": 1500,
"docs/AGENTS.md": 1250,
"docs/architecture.md": 3950,
"docs/defensive-patterns.md": 550,
"docs/testing.md": 800,
"examples/AGENTS.md": 600,
"packages/AGENTS.md": 600,
"packages/README.md": 1900
"packages/AGENTS.md": 450,
"packages/README.md": 600
}

2
scripts/verify-md-wrap.ts
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@@ -1,6 +1,6 @@
/**
* Doc-sync gate: enforce the repo's "Markdown is not hard-wrapped" convention
* (AGENTS.md § Type Safety and Documentation) — prose paragraphs are written as
* (docs/AGENTS.md § Writing rules) — prose paragraphs are written as
* one physical line per paragraph and the editor soft-wraps. A hard-wrapped
* paragraph (a one-word edit reflows and re-diffs the whole block) is a defect
* this script catches before review.