Start a local CLI subagent

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

The description discloses important behavior beyond annotations: the call returns immediately without waiting, and the launched provider may read, write, or run commands in cwd subject to native permission controls. This adds meaningful safety and async semantics that annotations alone do not convey.

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 compact and front-loaded: the core behavior is stated first, follow-up observation guidance is second, and the side-effect caveat is third. Every sentence contributes necessary information without redundancy.

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?

The description covers the essential invocation flow and side-effect profile, and the output schema plus 100% parameter descriptions complete the picture. It does not mention the cancel_agent sibling or explicitly state that the returned ID works with it, but that is inferable from sibling context and not a critical gap.

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 100%, so the schema already documents all parameters, including cwd, prompt, provider, session_id, timeout_seconds, and provider_options. The description does not add further parameter-level meaning, but it does not need to because the schema carries the full load.

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 the specific action: start one subagent and return an in-memory invocation ID without waiting. It also names wait_agent, directly distinguishing this tool from siblings. The title reinforces the resource and action.

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?

The description gives clear usage context by stating that wait_agent should be used with the returned ID to observe the invocation. It does not explicitly mention cancellation or when not to use this tool, but the asynchronous-start versus observe/cancel relationship is evident.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.