@ds-hu/dsh-acp-plus

@ds-hu/dsh-acp-plus

A lossless ACP v1 agent bridge for the DeepSeek Harness, shipped as a DSH bundle.

It claims stdio, serves the ACP v1 methods a client expects, and emits two channels at once: a standard projection that any ACP client can render, and DSH-native detail carried in _meta.dsh plus the _dsh/* extension methods. The bundle disables the stock acp row and replaces it with this bridge.

Install

The profile must stack the base, the ACP application and this bundle:

{
  "name": "dsh-profile-acp-plus",
  "private": true,
  "dsh": {
    "profile": {
      "bundles": [
        "@deepseek-ai/dsh-base",
        "@deepseek-ai/dsh-acp-app",
        "@ds-hu/dsh-acp-plus"
      ],
      "patchReload": "startup"
    }
  }
}

dsh plugin --profile acp-plus add @ds-hu/dsh-acp-plus
dsh --profile acp-plus

@deepseek-ai/dsh-acp-app must stay in the list: it inserts the stock acp row that this bundle's patch disables, and it provides the acpAppStartup gate that the acp-plus plugin injects. The package is published to npm as @ds-hu/dsh-acp-plus. patchReload: "startup" is appropriate because the bridge claims stdio once per process.

Config

Set these on the acp-plus row.

Field	Type	Default	Meaning
provider	string, optional	none	Default DSH provider route for new ACP sessions.
model	string, optional	none	Default model id for new ACP sessions.
sessionListPageSize	natural	100	Maximum sessions returned per session/list page.
questionTimeoutMs	natural	660000	How long an interactive question waits for a client answer (backstop).
replayLimit	natural	0	Maximum events replayed by session/load; 0 replays all.

The bundled patch inserts:

- id: acp
  disabled: true

- insert:
    - id: acp-plus
      name: '@ds-hu/dsh-acp-plus'
      inject: [acpAppStartup]
      config:
        provider: deepseek-official
        model: deepseek-v4-flash

    - id: tool-ask-user
      name: '@deepseek-ai/dsh-tool-ask-user'
      config:
        mode: timed
        timeout: 600

dsh-base mounts the user-questions service; the model-facing tool is opt-in, so the patch inserts it. mode: timed lets the harness own the timeout (seconds) while questionTimeoutMs stays a slightly longer backstop for a vanished client.

ACP surface

Method	Behaviour
initialize	protocolVersion: 1; loadSession: true; promptCapabilities.image when the deployment supports image prompts (audio and embeddedContext are false); sessionCapabilities: {list, resume, close, fork}; advertises features in the response _meta.dsh.
authenticate	No-op; returns {}.
session/new	Creates a DSH agent; a non-empty additionalDirectories is rejected with -32602. Returns configOptions, optional modes and _meta.dsh.
session/load	Replays persisted history as session/update in seq order (capped by replayLimit), then resumes the agent; returns optional modes.
session/resume	Resumes a persisted session without replay; returns optional modes.
session/list	Paged session summaries; each item carries _meta.dsh.
session/close	Cancels pending waiters and closes the agent.
session/set_config_option	Applies model, reasoning_effort, approval_policy, sandbox_mode or plan_mode; returns the updated option set.
session/set_mode	Selects a DSH agent preset declared by the profile. DSH only allows this before the first turn; success emits current_mode_update.
session/prompt	Streams updates for the turn and returns a stopReason plus _meta.dsh.
session/cancel (notification)	Cancels the in-flight turn.
session/fork (unstable)	Forks a session with buildForkSeed and agents.create; the same handler is exposed as _dsh/session/fork; returns optional modes.

Not implemented, so they answer with the ACP unknown-method error -32601: logout, session/delete. The client's fs/* and terminal/* methods are never called; tool execution stays inside DSH's own filesystem and sandbox. Monetary cost is not reported — _meta.dsh.features.cost is false.

_meta and extensions

Every payload that allows _meta carries an envelope:

{ "_meta": { "dsh": { "v": 1, "kind": "update.tool_call", "native": { } } } }

v is the envelope version, kind is a stable tag (update.*, initialize, session-new, session-load, session-resume, session-list, session-list-item, session-close, session-config, prompt-result, session-fork, permission-request), and native is the originating DSH object.

Extension	Kind	Direction	Payload
_dsh/event	notification	agent → client	{v, sessionId, event} — one durable DSH event, in seq order.
_dsh/frame	notification	agent → client	{v, sessionId, frame} — one transient assistant-stream frame.
_dsh/user_questions	request	agent → client	{v, requestId, sessionId, timeoutMs, questions[]} → {answers: [{id, selected[], custom?}]}.
_dsh/session/fork	request	client → agent	Same params and result as session/fork; the result _meta.dsh carries lineage.

Permissions are one-shot: the bridge offers allow_once versus a reject/cancel outcome, and keeps no session-scoped grants. When a client cannot answer _dsh/user_questions (unsupported method, cancellation or timeout), the ask_user_question tool fails with a clear error rather than hanging.

Tests

pnpm --filter @ds-hu/dsh-acp-plus test        # unit tests under test/, integration excluded
pnpm --filter @ds-hu/dsh-acp-plus typecheck
pnpm test:unit                         # all workspace unit projects
pnpm test:integration                  # builds the package, then runs test/integration/
DSH_ACP_LIVE=1 pnpm --filter @ds-hu/dsh-acp-plus test:live   # real model turn + fork (opt-in)
pnpm test                              # root vitest projects

The integration project needs the bundle built (pnpm --filter @ds-hu/dsh-acp-plus build) because it boots a profile from dist/. It creates a throwaway DSH_HOME, symlinks this package into profiles/acp-plus/node_modules/, and drives dsh --profile acp-plus over stdio. The live project copies the operator's credentials into a throwaway home, so the real one is never mutated.