dsh-sessions

Adds session discovery, bounded message inspection, fresh-session creation, and message delivery to DeepSeek Harness.

1. Release: 0.1.1

This release provides four public agent tools:

• session_status for recent sessions or one exact session;
• session_read for bounded canonical message reads;
• session_create for creating a fresh session with an initial prompt;
• session_send for steering or following up an existing session.

It also provides the /sessions command family and supports explicit model provider, model, and thinking-effort selection during session creation.

2. Install the plugin

Install the published package into a DSH profile:

# With the DSH CLI:
dsh plugin --profile web add dsh-sessions@0.1.1

# Without the `dsh` CLI:
npm install dsh-sessions@0.1.1

The DSH profile installation is required for Harness to load the plugin. After upgrading, restart DSH and create a new agent session so the current tool registry is loaded.

For local development, build the package and install the checkout into the target profile:

pnpm build
dsh plugin --profile web add C:\path\to\dsh-plugins\sessions

3. Quick start

Create a child session, inspect it, read its conversation, and send a message:

session_create({ "prompt": "Reply with exactly READY and nothing else." })

session_status({ "session_id": "<SESSION_ID>" })

session_read({ "session_id": "<SESSION_ID>", "offset": 1, "limit": 20 })

session_send({
  "session_id": "<SESSION_ID>",
  "message": "Continue with the next step."
})

session_create returns a queued result containing the new session ID. Use that ID with the other tools.

4. Agent tools and command interface

Agent tools

Tool	Arguments	Behavior
session_status	session_id?, recent_n?	Lists recent sessions, or returns one exact status row. Defaults to the 50 most recently updated sessions.
session_read	session_id, offset?, limit?	Reads canonical conversation blocks without resuming or mutating the session.
session_create	prompt, preset?, model?, cwd?	Creates a fresh session and queues its initial prompt.
session_send	session_id, message, mode?	Sends to an existing session; mode defaults to steer.

An explicit creation model has this shape:

{
  "provider": "<PROVIDER>",
  "model": "<MODEL>",
  "reasoningEffort": "<LEVEL>"
}

The adapter validates the effort identifier against the selected model. The cwd option must be an existing absolute directory.

Slash commands

/sessions status [SESSION_ID] [--recent N]
/sessions read SESSION_ID [--offset N] [--limit N]
/sessions create PROMPT [--preset ID] [--provider PROVIDER --model MODEL] [--effort LEVEL] [--cwd PATH]
/sessions send SESSION_ID MESSAGE [--mode steer|followup]

The /sessions create flags map to the tool's nested model object. A JSON object with the same shape as session_create is also accepted.

5. Session lifecycle and delivery

• session_create only creates a fresh session and queues its initial prompt; it does not wait for model completion.
• session_status is inspection-only and defaults to 50 recent sessions.
• session_read uses a 1-based message-block offset and a maximum limit of
  1. It omits trace-only chunks, token deltas, and lifecycle records.
• session_send defaults to steer, which wakes an idle agent and targets the nearest step of a running agent.
• session_send({ mode: "followup" }) queues a separate next turn.
• Cold sessions are resumed only for an explicit session_send; status and read never resume them.

The returned send message_id confirms accepted inbox work. It does not mean that the target agent has finished processing the message.

6. E2E testing

Reusable prompt fixtures are in test/e2e/prompts. The recommended flow is create, capture the returned session_id, and substitute it into the status, read, and send prompts.

The exact registered names are required. session_send must not be replaced by the built-in send_message, which targets subagents and has different semantics.

7. Verify locally

pnpm typecheck
pnpm test -- --runInBand
pnpm build
pnpm pack --dry-run

The published package includes the generated lib directory, the plugin patch, the README, the implementation specification, and the reusable E2E prompt fixtures. Unit-test sources and development dependencies are not included.

8. Package scope

The plugin uses public DeepSeek Harness and Cordis APIs and does not modify DeepSeek Harness source code. dsh-loop owns recurring self-prompts for the current session; dsh-sessions owns cross-session inspection, creation, and message delivery. The legacy codex-session-communication plugin should only be composed for wait_sessions during the migration.

9. Documentation

• Implementation specification
• UI contract
• E2E prompt fixtures