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

Annotations already declare openWorldHint=true, idempotentHint=false, destructiveHint=false. The description adds genuinely useful context beyond that: it states the required missions:run token scope (auth requirement) and explains the pipeline stage semantics of a hand-off. It doesn't describe reversibility or side effects of the started run, so not a 5.

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?

Three sentences, front-loaded with the core action, then the mode-selection rules, then the auth requirement. Every sentence earns its place with no filler.

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?

For a 6-parameter tool with nested agents objects and no output schema, the description covers the trickiest parameter (startAt) plus the auth requirement. The agents override parameter is explained in the schema rather than the description, and no return behavior is given, but the schema compensates.

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 coverage is 100%, so the per-parameter descriptions carry most meaning (baseline 3). The description goes further by explaining the conditional relationship between startAt and the plan/prNumber parameters, which the schema documents only in isolation, adding real semantic value.

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?

States a specific action ("Hand a mission off to the AI agent team") that maps to the resource 'mission'. Clear verb+resource and it enumerates the pipeline stages the tool drives. It does not, however, distinguish itself from the sibling create_mission, which an agent might reasonably confuse with starting a run.

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?

Strong conditional guidance: omit startAt for default planner-first run, use builder+plan to skip to coding, use reviewer/qa with prNumber for an existing build. This tells the agent which mode to select. Missing any exclusion relative to the create_mission alternative, so not a 5.

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