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openclaw/docs/tools/subagents.md
Seb Slight 0768fc65d2 docs(subagents): simplify page and verify behavior/examples (#12761)
* docs(subagents): rewrite page for clarity with examples and Mintlify components

- Add Quick Start section with natural language usage examples
- Add step-by-step How It Works using <Steps> component
- Break configuration into focused subsections with code examples
- Add proper parameters table for sessions_spawn tool
- Document model resolution order (verified against codebase)
- Add interactive /subagents command examples in <AccordionGroup>
- Fix inaccurate tool deny list: document all 11 denied tools (was 4)
- Use <Tip>, <Note>, <Warning>, <Accordion> components throughout
- Add cross-agent spawning config example
- Add full configuration example in collapsible accordion
- Add See Also links to related pages
- All information preserved or verified against codebase

* docs(subagents): correct behavior and config defaults

- Fix model/thinking defaults to match runtime behavior
- Clarify model and thinking resolution order for sessions_spawn
- Remove incorrect claim that announce runs in child session
- Replace ANNOUNCE_SKIP note with NO_REPLY behavior
- Align announce status wording with runtime outcomes

* docs(subagents): clarify NO_REPLY vs ANNOUNCE_SKIP (#12761) (thanks @sebslight)
2026-02-09 11:50:53 -05:00

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summary, read_when, title
summary read_when title
Sub-agents: spawning isolated agent runs that announce results back to the requester chat
You want background/parallel work via the agent
You are changing sessions_spawn or sub-agent tool policy
Sub-Agents

Sub-Agents

Sub-agents let you run background tasks without blocking the main conversation. When you spawn a sub-agent, it runs in its own isolated session, does its work, and announces the result back to the chat when finished.

Use cases:

  • Research a topic while the main agent continues answering questions
  • Run multiple long tasks in parallel (web scraping, code analysis, file processing)
  • Delegate tasks to specialized agents in a multi-agent setup

Quick Start

The simplest way to use sub-agents is to ask your agent naturally:

"Spawn a sub-agent to research the latest Node.js release notes"

The agent will call the sessions_spawn tool behind the scenes. When the sub-agent finishes, it announces its findings back into your chat.

You can also be explicit about options:

"Spawn a sub-agent to analyze the server logs from today. Use gpt-5.2 and set a 5-minute timeout."

How It Works

The main agent calls `sessions_spawn` with a task description. The call is **non-blocking** — the main agent gets back `{ status: "accepted", runId, childSessionKey }` immediately. A new isolated session is created (`agent::subagent:`) on the dedicated `subagent` queue lane. When the sub-agent finishes, it announces its findings back to the requester chat. The main agent posts a natural-language summary. The sub-agent session is auto-archived after 60 minutes (configurable). Transcripts are preserved. Each sub-agent has its **own** context and token usage. Set a cheaper model for sub-agents to save costs — see [Setting a Default Model](#setting-a-default-model) below.

Configuration

Sub-agents work out of the box with no configuration. Defaults:

  • Model: target agents normal model selection (unless subagents.model is set)
  • Thinking: no sub-agent override (unless subagents.thinking is set)
  • Max concurrent: 8
  • Auto-archive: after 60 minutes

Setting a Default Model

Use a cheaper model for sub-agents to save on token costs:

{
  agents: {
    defaults: {
      subagents: {
        model: "minimax/MiniMax-M2.1",
      },
    },
  },
}

Setting a Default Thinking Level

{
  agents: {
    defaults: {
      subagents: {
        thinking: "low",
      },
    },
  },
}

Per-Agent Overrides

In a multi-agent setup, you can set sub-agent defaults per agent:

{
  agents: {
    list: [
      {
        id: "researcher",
        subagents: {
          model: "anthropic/claude-sonnet-4",
        },
      },
      {
        id: "assistant",
        subagents: {
          model: "minimax/MiniMax-M2.1",
        },
      },
    ],
  },
}

Concurrency

Control how many sub-agents can run at the same time:

{
  agents: {
    defaults: {
      subagents: {
        maxConcurrent: 4, // default: 8
      },
    },
  },
}

Sub-agents use a dedicated queue lane (subagent) separate from the main agent queue, so sub-agent runs don't block inbound replies.

Auto-Archive

Sub-agent sessions are automatically archived after a configurable period:

{
  agents: {
    defaults: {
      subagents: {
        archiveAfterMinutes: 120, // default: 60
      },
    },
  },
}
Archive renames the transcript to `*.deleted.` (same folder) — transcripts are preserved, not deleted. Auto-archive timers are best-effort; pending timers are lost if the gateway restarts.

The sessions_spawn Tool

This is the tool the agent calls to create sub-agents.

Parameters

Parameter Type Default Description
task string (required) What the sub-agent should do
label string Short label for identification
agentId string (caller's agent) Spawn under a different agent id (must be allowed)
model string (optional) Override the model for this sub-agent
thinking string (optional) Override thinking level (off, low, medium, high, etc.)
runTimeoutSeconds number 0 (no limit) Abort the sub-agent after N seconds
cleanup "delete" | "keep" "keep" "delete" archives immediately after announce

Model Resolution Order

The sub-agent model is resolved in this order (first match wins):

  1. Explicit model parameter in the sessions_spawn call
  2. Per-agent config: agents.list[].subagents.model
  3. Global default: agents.defaults.subagents.model
  4. Target agents normal model resolution for that new session

Thinking level is resolved in this order:

  1. Explicit thinking parameter in the sessions_spawn call
  2. Per-agent config: agents.list[].subagents.thinking
  3. Global default: agents.defaults.subagents.thinking
  4. Otherwise no sub-agent-specific thinking override is applied
Invalid model values are silently skipped — the sub-agent runs on the next valid default with a warning in the tool result.

Cross-Agent Spawning

By default, sub-agents can only spawn under their own agent id. To allow an agent to spawn sub-agents under other agent ids:

{
  agents: {
    list: [
      {
        id: "orchestrator",
        subagents: {
          allowAgents: ["researcher", "coder"], // or ["*"] to allow any
        },
      },
    ],
  },
}
Use the `agents_list` tool to discover which agent ids are currently allowed for `sessions_spawn`.

Managing Sub-Agents (/subagents)

Use the /subagents slash command to inspect and control sub-agent runs for the current session:

Command Description
/subagents list List all sub-agent runs (active and completed)
/subagents stop <id|#|all> Stop a running sub-agent
/subagents log <id|#> [limit] [tools] View sub-agent transcript
/subagents info <id|#> Show detailed run metadata
/subagents send <id|#> <message> Send a message to a running sub-agent

You can reference sub-agents by list index (1, 2), run id prefix, full session key, or last.

``` /subagents list ```
```
🧭 Subagents (current session)
Active: 1 · Done: 2
1) ✅ · research logs · 2m31s · run a1b2c3d4 · agent:main:subagent:...
2) ✅ · check deps · 45s · run e5f6g7h8 · agent:main:subagent:...
3) 🔄 · deploy staging · 1m12s · run i9j0k1l2 · agent:main:subagent:...
```

```
/subagents stop 3
```

```
⚙️ Stop requested for deploy staging.
```
``` /subagents info 1 ```
```
 Subagent info
Status: ✅
Label: research logs
Task: Research the latest server error logs and summarize findings
Run: a1b2c3d4-...
Session: agent:main:subagent:...
Runtime: 2m31s
Cleanup: keep
Outcome: ok
```
``` /subagents log 1 10 ```
Shows the last 10 messages from the sub-agent's transcript. Add `tools` to include tool call messages:

```
/subagents log 1 10 tools
```
``` /subagents send 3 "Also check the staging environment" ```
Sends a message into the running sub-agent's session and waits up to 30 seconds for a reply.

Announce (How Results Come Back)

When a sub-agent finishes, it goes through an announce step:

  1. The sub-agent's final reply is captured
  2. A summary message is sent to the main agent's session with the result, status, and stats
  3. The main agent posts a natural-language summary to your chat

Announce replies preserve thread/topic routing when available (Slack threads, Telegram topics, Matrix threads).

Announce Stats

Each announce includes a stats line with:

  • Runtime duration
  • Token usage (input/output/total)
  • Estimated cost (when model pricing is configured via models.providers.*.models[].cost)
  • Session key, session id, and transcript path

Announce Status

The announce message includes a status derived from the runtime outcome (not from model output):

  • successful completion (ok) — task completed normally
  • error — task failed (error details in notes)
  • timeout — task exceeded runTimeoutSeconds
  • unknown — status could not be determined
If no user-facing announcement is needed, the main-agent summarize step can return `NO_REPLY` and nothing is posted. This is different from `ANNOUNCE_SKIP`, which is used in agent-to-agent announce flow (`sessions_send`).

Tool Policy

By default, sub-agents get all tools except a set of denied tools that are unsafe or unnecessary for background tasks:

| Denied tool | Reason | |-------------|--------| | `sessions_list` | Session management — main agent orchestrates | | `sessions_history` | Session management — main agent orchestrates | | `sessions_send` | Session management — main agent orchestrates | | `sessions_spawn` | No nested fan-out (sub-agents cannot spawn sub-agents) | | `gateway` | System admin — dangerous from sub-agent | | `agents_list` | System admin | | `whatsapp_login` | Interactive setup — not a task | | `session_status` | Status/scheduling — main agent coordinates | | `cron` | Status/scheduling — main agent coordinates | | `memory_search` | Pass relevant info in spawn prompt instead | | `memory_get` | Pass relevant info in spawn prompt instead |

Customizing Sub-Agent Tools

You can further restrict sub-agent tools:

{
  tools: {
    subagents: {
      tools: {
        // deny always wins over allow
        deny: ["browser", "firecrawl"],
      },
    },
  },
}

To restrict sub-agents to only specific tools:

{
  tools: {
    subagents: {
      tools: {
        allow: ["read", "exec", "process", "write", "edit", "apply_patch"],
        // deny still wins if set
      },
    },
  },
}
Custom deny entries are **added to** the default deny list. If `allow` is set, only those tools are available (the default deny list still applies on top).

Authentication

Sub-agent auth is resolved by agent id, not by session type:

  • The auth store is loaded from the target agent's agentDir
  • The main agent's auth profiles are merged in as a fallback (agent profiles win on conflicts)
  • The merge is additive — main profiles are always available as fallbacks
Fully isolated auth per sub-agent is not currently supported.

Context and System Prompt

Sub-agents receive a reduced system prompt compared to the main agent:

  • Included: Tooling, Workspace, Runtime sections, plus AGENTS.md and TOOLS.md
  • Not included: SOUL.md, IDENTITY.md, USER.md, HEARTBEAT.md, BOOTSTRAP.md

The sub-agent also receives a task-focused system prompt that instructs it to stay focused on the assigned task, complete it, and not act as the main agent.

Stopping Sub-Agents

Method Effect
/stop in the chat Aborts the main session and all active sub-agent runs spawned from it
/subagents stop <id> Stops a specific sub-agent without affecting the main session
runTimeoutSeconds Automatically aborts the sub-agent run after the specified time
`runTimeoutSeconds` does **not** auto-archive the session. The session remains until the normal archive timer fires.

Full Configuration Example

```json5 { agents: { defaults: { model: { primary: "anthropic/claude-sonnet-4" }, subagents: { model: "minimax/MiniMax-M2.1", thinking: "low", maxConcurrent: 4, archiveAfterMinutes: 30, }, }, list: [ { id: "main", default: true, name: "Personal Assistant", }, { id: "ops", name: "Ops Agent", subagents: { model: "anthropic/claude-sonnet-4", allowAgents: ["main"], // ops can spawn sub-agents under "main" }, }, ], }, tools: { subagents: { tools: { deny: ["browser"], // sub-agents can't use the browser }, }, }, } ```

Limitations

- **Best-effort announce:** If the gateway restarts, pending announce work is lost. - **No nested spawning:** Sub-agents cannot spawn their own sub-agents. - **Shared resources:** Sub-agents share the gateway process; use `maxConcurrent` as a safety valve. - **Auto-archive is best-effort:** Pending archive timers are lost on gateway restart.

See Also