feat(subagent): default continuable delegation to background

docs/tool-catalog.md

@@ -32,7 +32,7 @@ This table connects model-visible tool names to the plugin package and service s
 | `@deepseek-ai/dsh-tool-ralph` | `ralph` | `ctx.tools`, `ctx.workflows`, `ctx.subagents`, `ctx.systemPrompt`, `a calling Agent (exec.agent parents every fresh round)` | `tool/call`, `tool/result`, `workflow and child session events during execution` | - | A fixed foreground workflow starts one fresh structured child per round; the model selects only the immutable objective and an optional round cap. |
 | `@deepseek-ai/dsh-tool-skill` | `skill` | `ctx.tools`, `ctx.agents`, `ctx.skills` | `tool/call`, `tool/result`, `user/message replacement catalogs via agent.inject()` | - | - |
 | `@deepseek-ai/dsh-tool-session-query` | `session_event_read`, `session_event_search`, `session_event_trace`, `session_search`, `session_trace` | `ctx.tools`, `ctx.systemPrompt`, `ctx.sessionQuery`, `a calling Agent for workspace authority` | `tool/call`, `tool/result` | - | The five read-only tools hide provider cursors and authorize every result from the immutable calling agent session. The package is opt-in; compositions that need enforced deadlines or bounded inline output also mount the generic timeout or spill policies. |
-| `@deepseek-ai/dsh-tool-subagent` | `subagent` | `ctx.tools`, `ctx.subagents` | `tool/call`, `tool/result`, `child session events through the chosen provider` | `subagent`, `subagent_fork` | The registered tool name is the load-time `toolName` config (default `subagent`); the schema above is that default. The shipped compositions load this package once per subagent backend, so the model additionally sees `subagent_fork` bound to the fork backend. Each instance's description and `run_in_background` parameter follow its own `backgroundMode` and `enableRunInBackground`, so the two shipped schemas are not identical: `subagent` is `continuable`, while `subagent_fork` stays `one-shot` — see `packages/bundle/base/cordis.patch.yml` and `examples/acp-agent/cordis.yml`. |
+| `@deepseek-ai/dsh-tool-subagent` | `subagent` | `ctx.tools`, `ctx.subagents`, `ctx.systemPrompt` | `tool/call`, `tool/result`, `child session events through the chosen provider` | `subagent`, `subagent_fork` | The registered tool name is the load-time `toolName` config (default `subagent`); the schema above is that default. The shipped compositions load this package once per subagent backend, so the model additionally sees `subagent_fork` bound to the fork backend. Each instance's description, `run_in_background` parameter, and system-prompt policy follow its own `backgroundMode` and `enableRunInBackground`, so the two shipped schemas are not identical: `subagent` is `continuable` and defaults omitted calls to background with automatic settlement delivery, while `subagent_fork` stays `one-shot` and defaults them to foreground — see `packages/bundle/base/cordis.patch.yml` and `examples/acp-agent/cordis.yml`. |
 | `@deepseek-ai/dsh-tool-subagent-control` | `interrupt_agent`, `list_agents`, `send_message` | `ctx.tools`, `ctx.subagents`, `ctx.agents and ctx.sessionProjections (list_agents only)` | `tool/call`, `tool/result`, `child session events through ctx.subagents` | - | The globally named control tools over continuable background subagents: provider-bound `tool-subagent` instances register distinct delegation tools, while this package registers `send_message` and `interrupt_agent` once, plus `list_agents` from its separately loaded `/list-agents` plugin (whose catalog rows use the sessionProjections and live Agent registries). |
 | `@deepseek-ai/dsh-tool-subagent-report` | `report` | `ctx.subagents`, `ctx.systemPrompt`, `a live continuable in-process child Agent` | `tool/call`, `tool/result`, `a user-role message in the direct parent session` | - | Registered per continuable in-process child rather than globally, so this schema is visible only inside such a child and survives its global `toolFilter`. The same contribution installs the child-scoped `tool:report` prompt section, which this catalog does not render. The parent-facing `send_message` tool is installed independently. |
 | `@deepseek-ai/dsh-tool-tasks` | `task_kill`, `task_list`, `task_output` | `ctx.tools`, `ctx.tasks`, `ctx.systemPrompt` | `tool/call`, `tool/result`, `user/message via agent.inject() for background completion notices` | - | The kind-agnostic background-task controller: background bash commands, PTY sends, and subagents are read, listed, and killed through the same three tools. Loading the plugin attaches the controller that arms producers' `ctx.tasks.start()`. |
@@ -1278,7 +1278,7 @@ The five read-only tools hide provider cursors and authorize every result from t
 
 ### `subagent`
 
-Delegate a self-contained task to a subagent (a separate agent that works in its own context) and return its final result. Use this to offload focused, independent work — research, a scoped implementation, an analysis — so it does not consume this conversation's context. The subagent runs to completion and you receive only its final answer, not its intermediate steps. Give it a complete, standalone prompt: it does not see this conversation. Set `run_in_background: true` to return a task id; collect with `task_output` and stop with `task_kill`.
+Delegate a self-contained task to a subagent (a separate agent that works in its own context) to offload focused, independent work — research, a scoped implementation, an analysis — so it does not consume this conversation's context. The subagent returns its result, not its intermediate steps. Give it a complete, standalone prompt: it does not see this conversation. This call waits for the result by default. Set `run_in_background: true` to return a task id; collect with `task_output` and stop with `task_kill`.
 
 ```json
 {
@@ -1294,7 +1294,7 @@ Delegate a self-contained task to a subagent (a separate agent that works in its
     },
     "run_in_background": {
       "type": "boolean",
-      "description": "Run as a background task and return its id; collect with task_output or stop with task_kill."
+      "description": "Whether to run as a background task and return its id. Defaults to false; collect with task_output or stop with task_kill."
     }
   },
   "required": [
@@ -1306,7 +1306,7 @@ Delegate a self-contained task to a subagent (a separate agent that works in its
 
 Source: [`packages/subagent/tool-subagent/src/index.ts`](../packages/subagent/tool-subagent/src/index.ts)
 
-The registered tool name is the load-time `toolName` config (default `subagent`); the schema above is that default. The shipped compositions load this package once per subagent backend, so the model additionally sees `subagent_fork` bound to the fork backend. Each instance's description and `run_in_background` parameter follow its own `backgroundMode` and `enableRunInBackground`, so the two shipped schemas are not identical: `subagent` is `continuable`, while `subagent_fork` stays `one-shot` — see `packages/bundle/base/cordis.patch.yml` and `examples/acp-agent/cordis.yml`.
+The registered tool name is the load-time `toolName` config (default `subagent`); the schema above is that default. The shipped compositions load this package once per subagent backend, so the model additionally sees `subagent_fork` bound to the fork backend. Each instance's description, `run_in_background` parameter, and system-prompt policy follow its own `backgroundMode` and `enableRunInBackground`, so the two shipped schemas are not identical: `subagent` is `continuable` and defaults omitted calls to background with automatic settlement delivery, while `subagent_fork` stays `one-shot` and defaults them to foreground — see `packages/bundle/base/cordis.patch.yml` and `examples/acp-agent/cordis.yml`.
 
 ## `@deepseek-ai/dsh-tool-subagent-control`