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

Annotations already declare non-destructive, idempotent, non-read-only behavior, so the bar is lower; the description adds genuinely useful semantics by noting cancellation is not immediate ('stops at the next stage boundary') and that no partial output is retained ('keeps nothing'). It still omits whether the job_id remains queryable afterward and what the response contains.

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?

Two short sentences, front-loaded with the action, with no filler. Every clause carries information about scope or timing.

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 single-parameter tool with no output schema and annotations covering safety, the description is nearly complete on behavior, but it never tells the agent where to obtain job_id or what happens to the job record after cancellation — the one real gap for correct invocation.

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?

One parameter with 0% schema description coverage, and the description never explains job_id — where it comes from (presumably start_generation) or its format. It only implicitly links the param to a 'running job', so it does not compensate for the documentation gap.

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 verb and resource ('Stop a running start_generation job') and names the sibling tool that creates the job, so an agent can distinguish it from start_generation, get_status, and the other siblings without opening a schema.

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?

Usage is implied by the pairing with start_generation, but there is no explicit statement of when to cancel versus checking status (get_status) or letting the job finish. No exclusions or prerequisites are given.

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