Merge remote-tracking branch 'origin/worktree-simplify-branded-ids' into worktree-simplify-agent-stop

# Conflicts:
#	docs/rfc/README.md
This commit is contained in:
Tianyi Cui
2026-06-21 20:17:29 +08:00
6 changed files with 34 additions and 28 deletions

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@@ -73,6 +73,9 @@ packages/ Harness packages, grouped by role at packages/<group>/<pkg>/.
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)
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). echo-agent
= mock model + echo tool + stdio UI + JSONL persistence, wired via
cordis.yml. coding-agent = the real thing: DeepSeek V4 + bash tools

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@@ -93,7 +93,7 @@ Do NOT write one for a mechanical or local choice (a variable name, a one-file r
| [Drop the mutable session summary](implemented/simplification/2026-06-19-drop-mutable-session-summary.md) | 2026-06-19 |
| [Drop unconsumed assembled LLM convenience surfaces](implemented/simplification/2026-06-20-drop-unconsumed-llm-assembled-surfaces.md) | 2026-06-20 |
| [Drop the unconsumed `llm/adapter-change` event](implemented/simplification/2026-06-20-drop-unconsumed-llm-adapter-change-event.md) | 2026-06-20 |
| [Prune dead methods from the persistence and bash seams](implemented/simplification/2026-06-20-prune-dead-seam-methods.md) | 2026-06-20 |
| [Prune dead methods from the persistence seam](implemented/simplification/2026-06-20-prune-dead-seam-methods.md) | 2026-06-20 |
| [Keep one public stop primitive](implemented/simplification/2026-06-20-public-agent-stop-surface.md) | 2026-06-20 |
### Architecture

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@@ -4,7 +4,7 @@ Status: implemented (proposed and accepted 2026-06-20)
## Problem
The harness already brands three identifiers — `CallId` (`packages/llm/llm/src/brand.ts`), `SessionId` (`packages/core/session/src/types.ts`), and `AgentId` (`packages/core/agent/src/types.ts`) — using the `Branded<B> = string & { readonly [BRAND]: B }` machinery and a zero-cost cast factory per type. `brand.ts` also states the governing policy: *"Branding is for IDs that cross package boundaries and could plausibly be confused; not every string needs a brand."* That policy is right; the problem is that it is only half-applied. Two gaps let a structurally-identical-but-semantically-wrong string slip through the type checker today.
The harness already brands three identifiers — `CallId` (`packages/llm/llm/src/brand.ts`), `SessionId` (`packages/core/session/src/types.ts`), and `AgentId` (`packages/core/agent/src/types.ts`) — using the `Branded<B> = string & { readonly [BRAND]: B }` machinery (owned by the type-only `@deepseek-ai/dsh-brand` package at `packages/util/brand/` — see its [README](../../../../packages/util/brand/README.md)) and a zero-cost cast factory per type. `dsh-brand` also states the governing policy: *"Branding is for ids that cross package boundaries and could plausibly be confused; not every string needs a brand."* That policy is right; the problem is that it is only half-applied. Two gaps let a structurally-identical-but-semantically-wrong string slip through the type checker today.
**Gap 1 — unbranded cross-boundary IDs in the bash seam.** The background-task id is a plain `string`: `BashTask.id: string` (`packages/bash/bash/src/types.ts`), carried as `string` through the whole executor seam (`BashExecutor.get`/`ownerOf`/`readOutput`/`kill(id: string)` in `packages/bash/bash/src/index.ts`) and validated/passed as `string` by the model-facing tools (`validateTaskId`, `assertTaskAccess`, the `task_id` schema arg in `packages/bash/tool-bash/src/index.ts`). It is generated by a per-executor counter — `` `bash-${this.nextTaskId++}` `` in `packages/bash/bash-local/src/index.ts` — which gives it **exactly the same `name-N` shape as `SessionId`'s default** (`` `session-${++counter}` `` in `packages/core/session/src/index.ts`). A bash task id and a session id are trivially swappable at a call site and the compiler says nothing. This is the headline case the user asked about, and it is a model-facing id (the model passes `task_id` back to `bash_output`/`bash_kill`), so a confusion here is reachable from untrusted input.
@@ -16,7 +16,7 @@ The bash **owner token** is the related sub-case: `BashExecRequest.owner?: strin
A type-only change. Brands are zero-cost casts; nothing about runtime behavior, serialization, comparison, or the wire format changes. The work is in three parts, all honoring the existing "not every string" policy.
- **Brand the bash task id.** Add `BashTaskId = Branded<'BashTaskId'>` plus its same-named factory in `packages/bash/bash/src/types.ts` (the package that *owns* the id), importing `Branded` from `@deepseek-ai/dsh-llm` exactly as `SessionId`/`AgentId` already do. Thread it through `BashTask.id`, the `BashExecutor` seam methods (`get`/`ownerOf`/`readOutput`/`kill`), the generation site in `dsh-bash-local` (brand the counter output once, at creation), and the `dsh-tool-bash` validate/access surface (`validateTaskId` returns a `BashTaskId`; `task_id` is branded at the tool boundary where the model's string arrives).
- **Brand the bash task id.** Add `BashTaskId = Branded<'BashTaskId'>` plus its same-named factory in `packages/bash/bash/src/types.ts` (the package that *owns* the id), importing `Branded` from `@deepseek-ai/dsh-brand` exactly as `SessionId`/`AgentId` already do. The brand primitive lives in the dependency-free `dsh-brand` utility package precisely so `dsh-bash` can brand its ids by depending on it alone — it never pulls in `dsh-llm` (or `dsh-session`) just to reach `Branded`. Thread it through `BashTask.id`, the `BashExecutor` seam methods (`get`/`ownerOf`/`readOutput`/`kill`), the generation site in `dsh-bash-local` (brand the counter output once, at creation), and the `dsh-tool-bash` validate/access surface (`validateTaskId` returns a `BashTaskId`; `task_id` is branded at the tool boundary where the model's string arrives).
- **Mint a distinct `OwnerToken` brand.** Add `OwnerToken = Branded<'OwnerToken'>` in `packages/bash/bash/src/types.ts`; type `BashExecRequest.owner` / `BashExecSpec.owner` / `BashExecutor.ownerOf` as `OwnerToken | undefined`. The `dsh-tool-bash` consumer casts the agent's `session.header.id` (a `SessionId`) into an `OwnerToken` at the boundary — the one place the two vocabularies meet. The bash seam never imports `dsh-session`. (Rationale in the next section.)
@@ -25,7 +25,7 @@ A type-only change. Brands are zero-cost casts; nothing about runtime behavior,
Illustrative shape (the factory pattern is identical to the three existing brands):
```ts ignore-check
import type { Branded } from '@deepseek-ai/dsh-llm'
import type { Branded } from '@deepseek-ai/dsh-brand'
/** A background bash task handle (generated `bash-N` by the local executor). */
export type BashTaskId = Branded<'BashTaskId'>

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@@ -6,46 +6,37 @@ Status: implemented (proposed and accepted 2026-06-20)
## Problem
Two capability seams ([interface / implementation / consumer](../../implemented/architecture/2026-06-13-capability-seams.md)) carry abstract methods that no consumer calls. The seam exists to let implementations and consumers evolve independently — but a method no consumer programs against is not a seam, it is speculative surface every implementation must still implement and test.
A capability seam ([interface / implementation / consumer](../../implemented/architecture/2026-06-13-capability-seams.md)) carries abstract methods that no consumer calls. The seam exists to let implementations and consumers evolve independently — but a method no consumer programs against is not a seam, it is speculative surface every implementation must still implement and test.
### `SessionPersistence.has()` and `.delete()`
The abstract service declares four operations beyond create/append: `load`, `list`, `has`, `delete` ([packages/session-persistence/session-persistence/src/index.ts:142-151](../../../../packages/session-persistence/session-persistence/src/index.ts)). Production consumers of `ctx.sessionPersistence` use only two of them: the agent-loop resume path calls `load()` ([packages/core/agent-loop/src/index.ts:176-194](../../../../packages/core/agent-loop/src/index.ts)), and the ACP bridge calls `list()` for `session/list` ([packages/ui/acp/src/index.ts](../../../../packages/ui/acp/src/index.ts)). Grepping every `sessionPersistence.*` / `persistence.*` use across `packages/*/src` and `examples/` finds no `has(` and no `delete(` on the service. The `.has(`/`.delete(` calls in `packages/ui/acp/src/index.ts` are on the in-memory `SessionStore` and a local `Set` of loading ids, not persistence. The only callers of `has`/`delete` are the contract suites and per-backend specs.
The abstract service declared its operations beyond create/append: `load`, `list`, `has`, `delete`. Production consumers of `ctx.sessionPersistence` use only two: the agent-loop resume path calls `load()` ([packages/core/agent-loop/src/index.ts:176](../../../../packages/core/agent-loop/src/index.ts)), and the ACP bridge calls `list()` for `session/list` ([packages/ui/acp/src/index.ts:494](../../../../packages/ui/acp/src/index.ts)). Grepping every `sessionPersistence.*` / `persistence.*` use across `packages/*/src` and `examples/` finds no `has(` and no `delete(` on the service. The `.has(`/`.delete(` calls in `packages/ui/acp/src/index.ts` are on the in-memory `SessionStore` and a local `Set` of loading ids, not persistence. The only callers of `has`/`delete` were the contract suites and per-backend specs.
`has()` is not just unused — it is the most intricate branch in the shared coordinator: a tracked-vs-untracked dual-probe (`loadLive(id, cwd)` for a live-tracked session vs `loadStored(id)` for an untracked one) with a multi-line rationale ([packages/session-persistence/session-persistence/src/coordinator.ts:298-310](../../../../packages/session-persistence/session-persistence/src/coordinator.ts)). `delete()` drags the `deleteStored` backend hook ([coordinator.ts:99](../../../../packages/session-persistence/session-persistence/src/coordinator.ts), [coordinator.ts:313-319](../../../../packages/session-persistence/session-persistence/src/coordinator.ts)) that every backend must implement. This is the [drop-mutable-session-summary](../../implemented/simplification/2026-06-19-drop-mutable-session-summary.md) pattern: a contract test exercises both, but no shipping code asks "is this session persisted?" or removes one.
### `BashExecutor.get()` and `.list()`
The bash seam declares `get(id)` ("look up a background task by id") and `list()` ("all tracked background tasks") ([packages/bash/bash/src/index.ts:88-107](../../../../packages/bash/bash/src/index.ts)), both implemented by `LocalBashExecutor` ([packages/bash/bash-local/src/index.ts:179-191](../../../../packages/bash/bash-local/src/index.ts)). The sole production consumer — `dsh-tool-bash` — drives tasks via `ownerOf`, `onTaskDone`, `start`, `readOutput`, `kill`, `resolve`, `run`; it never calls `get`/`list` in shipping code, and there is no `bash_list` tool exposing a task roster to the model. So both are dead production seam surface. They are used by tests, more broadly than a single idiom: the bash seam/executor specs assert them directly ([packages/bash/bash/tests/service.spec.ts](../../../../packages/bash/bash/tests/service.spec.ts), [packages/bash/bash-local/tests/executor.spec.ts](../../../../packages/bash/bash-local/tests/executor.spec.ts) both call `get()`/`list()`), and several `dsh-tool-bash` tests reach through `ctx.bash.get(id)` to await a task's `done`, read its `status`, or inspect task fields ([packages/bash/tool-bash/tests/tools.spec.ts](../../../../packages/bash/tool-bash/tests/tools.spec.ts), [packages/bash/tool-bash/tests/integration.spec.ts](../../../../packages/bash/tool-bash/tests/integration.spec.ts)). These are test-harness conveniences, not shipping consumers — but they are real test code an implementing PR must migrate or delete.
`has()` was not just unused — it was the most intricate branch in the shared coordinator: a tracked-vs-untracked dual-probe (`loadLive(id, cwd)` for a live-tracked session vs `loadStored(id)` for an untracked one) with a multi-line rationale. `delete()` dragged the `deleteStored` backend hook that every backend had to implement. This is the [drop-mutable-session-summary](../../implemented/simplification/2026-06-19-drop-mutable-session-summary.md) pattern: a contract test exercised both, but no shipping code asks "is this session persisted?" or removes one.
## Proposal
Remove the methods nothing consumes, from the abstract seam, the implementation, and the contract/spec suites that exist only to exercise them:
- `SessionPersistence.has()` / `.delete()`: delete the abstract declarations, the coordinator's `has`/`delete`/`deleteCore`, and the `PersistenceBackend.deleteStored` hook. Remove the `has`/`delete` rows from the contract suite and the per-backend specs (jsonl + sqlite each implement `deleteStored` only to satisfy the hook — that implementation goes too). The backends are the [dual-backend](../../implemented/architecture/2026-06-14-session-persistence.md) design and otherwise out of scope, but removing a hook they implement for no consumer is part of removing the hook, not a backend redesign.
- `BashExecutor.get()` / `.list()`: delete the abstract declarations and the `LocalBashExecutor` impls. The seam/executor specs that assert `get()`/`list()` directly (`bash/tests/service.spec.ts`, `bash-local/tests/executor.spec.ts`) lose those assertions (the behavior is being removed). The `dsh-tool-bash` tests that reach through `ctx.bash.get(id)` to await `done`, read `status`, or inspect task fields switch to the public completion/status seam they should use — `onTaskDone` (or the `done` promise and status the `start()` return already exposes) — keeping their coverage without the removed lookup method.
- Update every doc and source-comment reference to the removed methods — not only literal `has(`/`delete(`/`get(`/`list(`/`deleteStored` call spellings, but also `{@link has}`/`{@link delete}` JSDoc links and prose that counts the methods (removing 2 of the persistence service's 6 public methods makes any "six public methods" phrasing wrong). The implementing PR greps `has`/`delete`/`get`/`list`/`deleteStored`/`{@link `/`six ` across `docs/`, `packages/*/README.md`, and source comments, and fixes each. The known doc sites: the seam READMEs ([packages/session-persistence/session-persistence/README.md](../../../../packages/session-persistence/session-persistence/README.md)'s `has(id)`/`delete(id)` API row and its "delegates its six public service methods" prose → four, [packages/bash/bash/README.md](../../../../packages/bash/bash/README.md)'s `get(id)`/`list()` row), the backend READMEs that describe `has`/`list` semantics ([packages/session-persistence/session-persistence-sqlite/README.md](../../../../packages/session-persistence/session-persistence-sqlite/README.md), [packages/session-persistence/session-persistence-jsonl/README.md](../../../../packages/session-persistence/session-persistence-jsonl/README.md) — reword "absent from `has()`/`list()`" to just `list()`), the service-map / seam docs in [docs/architecture.md](../../../architecture.md), and the persistence prose in the [session-persistence RFC](../../implemented/architecture/2026-06-14-session-persistence.md) and [shared write-coordinator RFC](../../implemented/architecture/2026-06-18-shared-persistence-write-coordinator.md). The known source-comment sites: the abstract `create()` JSDoc's `{@link has}/{@link list}` link ([packages/session-persistence/session-persistence/src/index.ts](../../../../packages/session-persistence/session-persistence/src/index.ts) — drop the `has` link), the coordinator's "six public methods"/"six public service methods" module + class JSDoc and its lazy-materialization JSDoc justifying the `materialized` flag by "the signal `has`/`list` rely on" ([packages/session-persistence/session-persistence/src/coordinator.ts](../../../../packages/session-persistence/session-persistence/src/coordinator.ts)), the JSONL backend's `loadStored`/`deleteStored` comment, and the SQLite backend's `schema.ts` and `index.ts` comments that mention "absent from `has`/`list`" — all reworded to the surviving four-method, `list()`-only contract.
- `SessionPersistence.has()` / `.delete()`: delete the abstract declarations, the coordinator's `has`/`delete`/`deleteCore`, and the `PersistenceBackend.deleteStored` hook. Remove the `has`/`delete` rows from the contract suite and the per-backend specs (jsonl + sqlite each implemented `deleteStored` only to satisfy the hook — that implementation goes too). The backends are the [dual-backend](../../implemented/architecture/2026-06-14-session-persistence.md) design and otherwise out of scope, but removing a hook they implement for no consumer is part of removing the hook, not a backend redesign.
- Update every doc and source-comment reference to the removed methods — not only literal `has(`/`delete(`/`deleteStored` call spellings, but also `{@link has}`/`{@link delete}` JSDoc links and prose that counts the methods (removing 2 of the persistence service's 6 public methods makes any "six public methods" phrasing wrong). The implementing PR greps `has`/`delete`/`deleteStored`/`{@link `/`six ` across `docs/`, `packages/*/README.md`, and source comments, and fixes each. The known doc sites: the seam README ([packages/session-persistence/session-persistence/README.md](../../../../packages/session-persistence/session-persistence/README.md)'s `has(id)`/`delete(id)` API row and its "delegates its six public service methods" prose → four), the backend READMEs that describe `has`/`list` semantics ([packages/session-persistence/session-persistence-sqlite/README.md](../../../../packages/session-persistence/session-persistence-sqlite/README.md), [packages/session-persistence/session-persistence-jsonl/README.md](../../../../packages/session-persistence/session-persistence-jsonl/README.md) — reword "absent from `has()`/`list()`" to just `list()`), the service-map / seam docs in [docs/architecture.md](../../../architecture.md), and the persistence prose in the [session-persistence RFC](../../implemented/architecture/2026-06-14-session-persistence.md) and [shared write-coordinator RFC](../../implemented/architecture/2026-06-18-shared-persistence-write-coordinator.md). The known source-comment sites: the abstract `create()` JSDoc's `{@link has}/{@link list}` link ([packages/session-persistence/session-persistence/src/index.ts](../../../../packages/session-persistence/session-persistence/src/index.ts) — drop the `has` link), the coordinator's "six public methods"/"six public service methods" module + class JSDoc and its lazy-materialization JSDoc justifying the `materialized` flag by "the signal `has`/`list` rely on" ([packages/session-persistence/session-persistence/src/coordinator.ts](../../../../packages/session-persistence/session-persistence/src/coordinator.ts)), the JSONL backend's `loadStored`/`deleteStored` comment, and the SQLite backend's `schema.ts` and `index.ts` comments that mention "absent from `has`/`list`" — all reworded to the surviving four-method, `list()`-only contract.
## Why not keep them as "the seam should be complete"?
The instinct that a persistence seam "should" offer delete, or a task executor "should" offer enumeration, is real — and it is exactly the speculative-completeness the pre-release stance warns against ([AGENTS.md](../../../../AGENTS.md): optimize for the correct foundation, not for hypothetical callers you do not have). Each of these is one method to re-add the day a consumer needs it:
- A session-management UI that deletes old sessions will want `delete()` — add it then, designed against that UI's real needs (soft-delete? cascade? confirmation?), not guessed now.
- A `bash_list` tool that shows the model its running tasks will want `list()` — add it with the tool.
The instinct that a persistence seam "should" offer delete is real — and it is exactly the speculative-completeness the pre-release stance warns against ([AGENTS.md](../../../../AGENTS.md): optimize for the correct foundation, not for hypothetical callers you do not have). `delete()` is one method to re-add the day a consumer needs it: a session-management UI that deletes old sessions will want it — add it then, designed against that UI's real needs (soft-delete? cascade? confirmation?), not guessed now.
Re-adding a seam method with a live consumer is cheap and better-designed than the speculative version, because the consumer pins the contract. Carrying it unused means every implementation (and every future backend) must implement and test a method that does nothing.
## Acceptance criteria
- `has`/`delete`/`deleteStored` are gone from the persistence seam, impl, and contract suites; `pnpm run knip` reports no new dead exports. (The bash `get`/`list` removal was reverted — see the implementation note above; those methods remain.)
- The remaining seam operations (`create`/`append`/`load`/`list` for persistence; `run`/`start`/`get`/`ownerOf`/`list`/`onTaskDone`/`readOutput`/`kill`/`resolve` for bash) are untouched; ACP `session/list`, bash tool flows, and crash-recovery behave identically.
- `has`/`delete`/`deleteStored` are gone from the persistence seam, impl, and contract suites; `pnpm run knip` reports no new dead exports.
- The remaining persistence operations (`create`/`append`/`load`/`list`) are untouched; ACP `session/list` and crash-recovery behave identically.
- `pnpm run test:coverage` stays 100% per-file (the contract/spec rows for the removed persistence methods are deleted with them).
- Persistence seam READMEs and `docs/architecture.md` no longer list the removed `has`/`delete` methods.
- The persistence seam README and `docs/architecture.md` no longer list the removed `has`/`delete` methods.
## Risks
- **`delete()` is the kind of operation a product eventually wants.** True — but "eventually" is the point. Deleting it now and re-adding it against a real consumer is strictly better than shipping a guessed contract. The dual backends each shed a `deleteStored` impl, which is a bounded edit in otherwise-out-of-scope packages.
- **`list()` on the bash seam is the natural seed for a future `bash_list`.** Acknowledged in the [pre-release foundation stance](../../../../AGENTS.md): add the seed when the tool lands. The executor still tracks tasks internally (the `tasks` map backs `ownerOf`/`readOutput`/`kill`); exposing an enumeration is a one-line re-add.
- **Low coupling.** Both removals are confined to their seam + impl + tests; no cross-package consumer references the removed methods, so there is no ripple beyond the docs.
- **Low coupling.** The removal is confined to the persistence seam + impl + tests; no cross-package consumer references the removed methods, so there is no ripple beyond the docs.
Modest size, but it converts two seams from "what an implementation must provide for nobody" back to "exactly what a consumer uses."
Modest size, but it converts the seam from "what an implementation must provide for nobody" back to "exactly what a consumer uses."

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@@ -14,17 +14,19 @@ Packages are grouped by modular role at `packages/<group>/<pkg>/`. The group dir
| [`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 |
| [`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).
## Dependency graph
```
dsh-llm (no harness deps — pure vocabulary)
dsh-bash (no harness deps — abstract executor seam)
dsh-session ← dsh-llm
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-agent ← dsh-llm, dsh-session, dsh-brand
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)
@@ -61,6 +63,7 @@ The rule: plugins depend on interfaces, never on the concrete loop. `dsh-agent-l
| `acp/` | `ui` | Agent Client Protocol bridge: serves the agent to an ACP editor over JSON-RPC stdio | (drives `ctx.agents`/`ctx.sessions`) |
| `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`) |
| `brand/` | `util` | Type-only `Branded<B>` nominal-typing primitive (no runtime code, no harness deps) | (none — type-only) |
Each package has its own `README.md` with purpose, service API, events, extension points, and deliberate non-goals (TODOs).

9
packages/util/README.md Normal file
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@@ -0,0 +1,9 @@
# util/ — low-level shared utilities
Zero-dependency primitives shared across the other groups. A package lands here when it owns a tiny, foundational type or helper that several capability families need but that belongs to none of them — keeping it out of any one group avoids a capability package depending on an unrelated one just to reach a shared primitive. These are **support** packages: small, stable, and free of harness dependencies.
| Package | Role |
|---|---|
| `brand/` | The type-only `Branded<B>` nominal-typing primitive (no runtime code, no harness deps) |
`dsh-brand` is the canonical case: it owns ONLY the `Branded<B>` helper, so a capability package can brand the ids it owns (`dsh-bash`'s `BashTaskId`/`OwnerToken`, `dsh-session`'s `SessionId`, …) by depending on `dsh-brand` alone, without pulling in an unrelated package just to reach `Branded`.