dsh-monitor

A drop-in replacement for Claude Code's Monitor tool, built for DeepSeek Harness.

dsh-monitor is a harness plugin that arms persistent, background watchers on message sources. When new content arrives, the plugin wakes the owning agent — delivering a plugin-sourced user message into the session, exactly like Claude Code's <task-notification> mechanism.

If you rely on Claude Code's Monitor to stay responsive to inbound messages while a shell is idle, this plugin gives you the same capability inside DeepSeek Harness.

How it works

The model calls the monitor tool to arm a watcher on a source:

• source: file — an append-only NDJSON inbox. New lines are delivered as they land.
• source: command — a shell command re-run on an interval. Its output delta since the last run is delivered.

On each new message the plugin wakes the agent:

Agent state	Behavior
idle	agent.followup() — opens a new turn (harness analog of Claude Code's <task-notification>)
busy	agent.inject() — queues the message into the next step

Watchers are durable within the session, disarmable on demand, and torn down automatically when the plugin is unloaded.

Installation

dsh plugin --profile <name> <args...> is a thin pnpm forwarder: it runs pnpm <args...> in the profile directory, then adds any installed package that declares dsh.bundle to the profile's layer stack automatically.

From npm

npx @deepseek-ai/dsh@latest plugin --profile web add dsh-monitor

From git

npx @deepseek-ai/dsh@latest plugin --profile web add https://github.com/AbnerAI/dsh-monitor

From a local directory

npx @deepseek-ai/dsh@latest plugin --profile web add /path/to/dsh-monitor

When installing a local directory, run pnpm install inside the package first — link: installs do not resolve the package's own dependencies automatically.

Manual alternative: add dsh-monitor to the profile's dsh.profile.bundles and include this package's cordis.patch.yml via its dsh.bundle.patch declaration.

Quick start

Tell the agent to arm a watcher on an inbox file:

monitor(source="file",
        path="/absolute/path/to/inbox.ndjson",
        name="my-inbox",
        poll_interval_ms=1000)

• path must be an absolute path (or start with ~ — the plugin expands it). Node's fs does not expand ~ itself.
• poll_interval_ms defaults to 2000; 1000 is a good balance for chat-like inboxes.

The tool returns a watcher id, e.g. monitor-1. From then on, every new line written to the file wakes the agent automatically.

Manage watchers at any time:

monitor_list                        # list armed watchers (id, source, delivered count)
monitor_stop(id="monitor-1")        # disarm one

To watch a command's changing output instead of a file:

monitor(source="command", command="tail -n 5 /var/log/app.log", poll_interval_ms=5000)

Tools

monitor

Arm a persistent watcher.

Parameter	Type	Required	Description
source	"file" | "command"	yes	file = watch an append-only NDJSON inbox; command = poll a shell command's output
path	string	for file	path of the NDJSON inbox (absolute, or ~-prefixed)
command	string	for command	shell command to poll
cwd	string	no	working directory for the command (defaults to the process cwd)
poll_interval_ms	number	no	poll interval in ms (default 2000)
name	string	no	short label used in wake-up messages and monitor_list

Returns a watcher id. Each new NDJSON line (or command-output delta) is delivered as a plugin-sourced notice that wakes the agent.

Implementation note. Polling uses plain global setInterval with cleanup registered via ctx.effect — the same timer convention as dsh-schedule. The Cordis timer-service mixin (ctx.setInterval) is intentionally not used: it is only resolvable from the host context, not from tool-execution contexts, and calling it throws cannot get property "timer" without inject.

monitor_list

List armed watchers with their ids, sources, and delivery counts. Empty output means nothing is armed.

monitor_stop

Disarm a watcher by id. Returns whether it was still armed.

NDJSON inbox format

Each line is a JSON object; the content field is delivered if present, otherwise the raw line:

{"content":"hello","ts":1712345678}

Any append-only NDJSON file works. The format pairs naturally with messaging and notification brokers: a broker appends one record per inbound message, and a watcher on the file wakes the agent as new records land. This mirrors the contract Claude Code Monitor exposes for its own inbox watchers.

Requirements

• DeepSeek Harness (dsh) with a Cordis-based plugin loader (bundles / cordis.patch.yml).
• Peer dependencies: dsh-agent, dsh-llm, dsh-tools, cordis (satisfied by the harness runtime).

License

MIT