dsh-mcp-manager

Manage Model Context Protocol servers inside DeepSeek Harness (DSH) from the Web UI:

• Settings → MCP servers: list, add, edit, remove, enable/disable and test servers.
• Composer + menu → MCP servers: turn any server on or off for the current session only.

Every configured server is mounted as a real @deepseek-ai/dsh-mcp-client instance, so its tools (mcp__<name>__<tool>), resources, and server instructions behave exactly like a hand-written MCP row in the profile.

Install

Requires a DSH build with the plugin system, e.g. DSH 0.2.1-rc.2 desktop.

1. Clone or copy this directory somewhere stable.
2. Install it as a profile bundle: Plugins → Add plugin → local directory, or the plugin manager tool's install_bundle with this folder's absolute path.
3. Keep the folder: a local-directory install is linked, not copied.

Use

Servers

Field	Notes
Name	Becomes the tool namespace mcp__<name>__<tool>. Letters, digits, _, -, max 32.
Transport	stdio for a local program, streamable-http for a remote service.
Command / arguments / working directory	stdio only; one argument per line.
Environment	stdio only; KEY=VALUE per line. Values may use ${ENV_VAR}.
URL / headers	streamable-http only; headers are Name: Value per line, ${ENV_VAR} allowed.
Enabled	Off means no connection and no tools.

Changes are staged as a draft and applied with Save. The host reconciles immediately: removed or edited servers are disconnected, new ones are connected.

Test mounts the server in an isolated scope and reports the tool count and names without touching the live tool list. ${ENV_VAR} references are expanded from the harness process environment; a missing variable fails that server with a clear message.

Servers that already exist as MCP rows in the profile (for example a mcp-anysearch row) are listed read-only under From the profile; their tools still participate in per-session switches.

Per-session switches

Open the composer's + menu (the same menu as / commands) and pick MCP servers. The same popup area that held the menu now shows the server list with tool counts and a switch per server:

• off → that server's tools are hidden from the agent (tools.restrict deny) and its mcp:<name> prompt section is dropped for this session;
• on → both come back.

Click outside or press Escape to close it, exactly like the command menu.

The state is a durable per-session plugin record (plugin:mcp-manager/toggles), so it survives reload and does not leak into other sessions. Subagents start with every server enabled.

How it works

• The host row owns one volatile servers config. apply mounts one child @deepseek-ai/dsh-mcp-client plugin per enabled server with ctx.plugin(...), so Cordis owns connection lifetime and disposal.
• system-prompt/assemble removes mcp:<name> sections for servers the session switched off.
• agent/created, agent/disposed and tools/change keep per-agent tool restrictions in sync; restrictions are recomputed as MCP tools appear or disappear.
• The browser half talks to a small same-origin JSON API (/dsh-mcp-manager/api/...) for status, tests, and session switches, renders its manager page as a settings.section page (Settings → MCP servers), and contributes a /mcp command whose action opens an overlay panel in conversation.input.overlay — the same anchor the composer popup menus use. It is unauthenticated like every other route on the loopback Web server — do not expose this host beyond loopback.

Compatibility and risk

• Developed against DSH 0.2.1-rc.2. It relies on plugin-facing APIs (ctx.plugin, tools.restrict, system-prompt/assemble, appendPluginRecord) that are not a public compatibility promise.
• A stdio server command runs with the harness process's environment. Only add servers you trust.
• Tool hiding is per session and per agent; it is not a security boundary against the model calling a tool through another provider.
• Removing a server does not delete anything it wrote; it only disconnects it.

Development

node --test test/model.test.mjs

lib/model.js is pure: server normalization, ${VAR} expansion, MCP tool-name mapping, and the dsh-mcp-client config builder, all testable without a harness.

License

MIT.