Delegate coding tasks to a Pi sub-agent via MCP with named sessions, choosing synchronous or asynchronous execution to match the task's needs.
委派任务给 Pi 子代理（默认 async）
| Name | Required | Description | Default |
|---|---|---|---|
| cwd | No | ||
| goal | No | ||
| mode | No | ||
| prompt | Yes | ||
| session | Yes | ||
| constraints | No | ||
| runTimeoutMs | No | ||
| allowUnknownTools | No |
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description must disclose behavioral traits but only mentions 'default async'. It does not explain side effects, how results are returned, or whether the tool is idempotent. Critical details are missing.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
The description is a single concise sentence, but it is overly terse for a tool with 8 parameters. While front-loaded, it lacks structure and does not fully utilize the space to convey necessary information.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
Given the complexity (8 parameters, nested objects, no output schema, no annotations), the description is severely incomplete. It fails to cover usage patterns, return values, or async/sync behavior beyond the default.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema description coverage is 0%, and the description does not explain any of the 8 parameters, not even the required 'prompt' and 'session'. The enum for 'mode' is mentioned only implicitly as 'default async' but no details.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description clearly states that the tool delegates tasks to a Pi sub-agent with a default async mode. However, it does not differentiate from sibling tools like pi_plan or pi_session_fork, which could have overlapping functionality.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
No guidance is provided on when to use this tool versus alternatives, nor are there any preconditions or exclusions mentioned. The description is too brief to inform decision-making.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.