610c8e3709
A scripted fake ACP agent bin (tests/fixtures/fake-acp-agent.ts) speaks real newline JSON-RPC through the REAL runScenario spawn path (tsx loader, temp cwd, env plumbing); every behavior — prompt outcome, session/new rejection, persisted logs, filesystem noise — comes from a behavior.json beside the fixture, so specs script whole subprocess runs from data. harness.spec.ts drives every step op, both expect-error arms, the permission-stub default, env forwarding, workspace seeding, and the harvest ordering/noise/fallback branches. suite.spec.ts runs the factory for real at collection time: a replay suite over committed synthetic fixtures and a record suite over a temp copy (write-back never touches the committed tree; ACP_SNAPSHOT_SPEC_BOOTSTRAP=1 re-bootstraps it), plus direct cases for the exported pure helpers. The suite factory's pure helpers (childFixturePaths, fixtureContext, normalizedHeaders, headerDeltaCount) are exported for those direct specs. Two branches carry justified v8 ignores, both structurally unreachable: the waiter in-bounds guard (noUncheckedIndexedAccess) and waitForExit's already-exited race guard (both call sites sit one synchronous frame after stdin.end()/kill()). The fake bin substitutes the session/new cwd, not process.cwd(), into scripted logs — the realpath difference (/private on darwin) is exactly what the real bin's header carries. packages/support/acp-snapshot/src is at 100% statements, branches, functions, and lines under the per-file gate.
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, declares its ctx key/events through declaration merging, and exposes extension points through ctx.effect(), ctx.on(), and ctx.waterfall(). Authoring conventions: AGENTS.md (subtree) and the root 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 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 |
|---|---|---|
core/ |
Product API spine: session, system-prompt, tools, agent, and the concrete loop | Product — stable surface |
llm/ |
LLM capability family: the abstract service + provider adapters | Product — stable surface |
bash/ |
Bash capability family: the executor seam, a local impl, and the model-facing tool | Product — stable surface |
fs/ |
Filesystem capability family: the abstract seam, a local impl, and the model-facing file tools | Product — stable surface |
compact/ |
Compaction capability family: the abstract seam + a basic backend (tool deferred) | Product — stable surface |
subagent/ |
Subagent capability family: the provider-registry seam and the model-facing delegation tool | Product — stable surface |
web/ |
Web capability family: the abstract seam, search/fetch provider impls, and the model-facing web tools | Product — stable surface |
todo/ |
Todo/planning family: the model-facing todo_write tool (whole-list task tracking on the session log) |
Product — stable surface |
hooks/ |
Hook bridges + the shared Claude Code / Codex wire-protocol library | Product — stable surface |
session-persistence/ |
Persistence capability family: the seam + JSONL/SQLite backends | Product — stable surface |
ui/ |
Editor/client integration surfaces (the ACP bridge) + the app packages | Product — stable surface |
support/ |
Dev/test/example infrastructure (invariants, replay adapter, subagent mock) | Support — lower compatibility expectations |
util/ |
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 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).
Dependencies
The inter-package dependency graph is generated: docs/module-graph.md (pnpm run gen-module-graph, freshness-gated in CI).
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).
Each package has its own README.md with purpose, service API, events, extension points, and deliberate non-goals (TODOs).