dsh-acp-plus

An extended Agent Client Protocol (ACP) server for DeepSeek Harness (dsh), packaged as an out-of-tree Cordis plugin and profile bundle.

It serves the standard ACP v1 surface and adds the capabilities the shipped automation-only @deepseek-ai/dsh-acp bridge deliberately omits — transcript replay, extra workspace roots, slash commands, plan mode, form elicitation, and mid-turn steering — without changing the harness core.

dsh --profile acp-plus

Features

• Standard ACP v1 — sessions (new / list / resume / close), prompts and cancellation, model and reasoning-effort config options, MCP servers (stdio and streamable HTTP), images, permissions, usage, and tool updates.
• session/load — reopen a persisted session, replay its transcript, and continue prompting across process restarts.
• Additional directories — declare extra workspace roots on a session; verified single-target writes inside them are pre-approved through the harness's existing sandbox escalation, while everything else still asks the client.
• Commands and modes — publish the harness command list, execute /name without a model turn, and advertise default / plan modes.
• Elicitation — bridge ask_user_question to the standard ACP elicitation/create form when the client declares support.
• Steering — the _session/steering extension injects text into a live turn at its next step, and hands the text back when the turn already ended.
• Default-model fallback — with no provider/model in its own config, the bridge follows the composition's agent-default-model (the same default the dsh Web Models page writes).

Requirements

• Node.js >= 22
• DeepSeek Harness (dsh) with a model route configured. The plugin's @deepseek-ai/dsh-* peers are pinned to the running harness version (^0.2.0-rc.1).

Install

From GitHub:

dsh plugin --profile acp-plus add github:AndPuQing/dsh-acp-plus

From a local checkout:

dsh plugin --profile acp-plus add .

The build output (lib/) is committed, so neither route runs a build script. After changing source, run npm run build and commit lib/ with the change.

To replace the native bridge inside the shipped acp profile instead:

dsh --profile acp --patch ./overlay-on-native-acp.yml

Usage

dsh --profile acp-plus

stdout carries only ACP JSON-RPC; diagnostics go to stderr. Connect any ACP client to the process.

Zed

Zed starts external agents through agent_servers. In a remote project the agent runs on the remote Zed server, so the setting belongs in the remote server settings (zed: open server settings, i.e. the remote ~/.config/zed/settings.json):

{
  "agent_servers": {
    "dsh-acp-plus": {
      "type": "custom",
      "command": "/bin/sh",
      "args": ["-lc", "exec dsh --profile acp-plus"],
      "env": {}
    }
  }
}

sh -lc picks up the login shell's PATH; an absolute dsh path works too. Reconnect the remote project and select dsh-acp-plus in the agent picker. Modes, slash commands, session/load replay, and ask_user_question (when the client declares form elicitation) are available; client terminals are intentionally unsupported. Logs: ~/.local/share/zed/logs/server-preview-*.log.

Configuration

The profile patch configures the bridge row:

Field	Type	Default	Description
provider	string	agent-default-model	Provider route for new agents (e.g. deepseek-official).
model	string	agent-default-model	Exact model id (e.g. deepseek-v4-flash).
sessionListPageSize	integer >= 1	100	Maximum sessions returned by one session/list page.
enableSessionLoad	boolean	false	Advertise and serve session/load transcript replay.
enableAdditionalDirectories	boolean	false	Accept additionalDirectories with containment-checked pre-approval.

The shipped profile enables both enableSessionLoad and enableAdditionalDirectories.

Inspect the composed configuration and its schema:

dsh --profile acp-plus --dump-config
dsh --profile acp-plus --dump-config-schema

Models and credentials

provider / model are optional. When unset, the bridge follows agent-default-model — the default model service the dsh Web Models page writes — so a deployment configures its model once and every entry point follows. Provider routes (llm-pi-ai providers) and the default model can be shared across profiles by putting them in $DSH_HOME/cordis.patch.yml.

Note that a DSH patch replaces the whole config object of the row it targets: overriding the acp-plus row requires restating sessionListPageSize, enableSessionLoad, and enableAdditionalDirectories. Configuring only the model does not touch that row.

API keys are home-level and shared by every profile ($DSH_HOME/.credentials.yaml, written by the Web Models page or supplied through the launch environment).

Relationship to the native bridge

The shipped @deepseek-ai/dsh-acp is automation-only by design. This project keeps its protocol semantics and extends them:

Capability	@deepseek-ai/dsh-acp	dsh-acp-plus
Sessions, prompts, cancel, MCP, images, config options	yes	yes (parity)
session/resume, session/list, session/close	yes	yes
session/load transcript replay	no	yes
additionalDirectories	no	yes
Commands, modes	no	yes
Form elicitation	no	yes
_session/steering	no	yes

Compatibility

• Standard ACP v1 plus the advertised session capabilities and the _session/steering extension; clients that do not know an extension ignore it.
• All @deepseek-ai/dsh-* peers are pinned to ^0.2.0-rc.1 and checked by dsh's plugin preflight. On a different harness version, grant the exact-version exemption the diagnostic describes (dsh plugin allow-version <name>@<version>).

Development

npm run build          # esbuild -> lib/ (rebuild and commit after source changes)
npm run check          # tsc, project files only
npm test               # keyless: esbuild-bundled tests -> node --test
npm run release:check  # build + manifest, profile, and peer checks

See DEVELOPMENT.md for the repository layout, hard constraints, and how the bridge tracks the native implementation.

License

MIT. Portions are derived from DeepSeek Harness, Copyright (c) 2026 DeepSeek, used under the MIT License.