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

Beyond the annotations it discloses the async nature (~1 minute, poll get_test_run), the per-account daily quota, and that the workflow itself is not modified — all context the annotations cannot convey. There is mild tension between 'it changes nothing' and readOnlyHint=false, but the quota disclosure explains why it is not classified read-only, so this reads as clarification rather than contradiction; the polling mechanics are the main thing spelled out well.

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 core capability and output list are front-loaded, and the follow-up and polling instructions come in a logical order. The language is chatty in places ('Talk about testing and improving, not "QA"') — that is a styling directive rather than invocation guidance, so it costs a little space but does not obscure the operational content.

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 one-parameter tool with no output schema, the description covers the return shape, the latency, the quota cost, the required polling loop, and the recommended next action. Nothing an agent needs to call it and interpret the result is missing.

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% for the single test_run_id parameter, so the baseline is 3. The description adds only a narrow constraint — the run must be 'finished' — which usefully implies drafts belong to test_run_draft, but no format or sourcing detail is added beyond the schema's own 'A finished test run.'

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 names a specific verb and resource ('Check a finished test run') and enumerates the concrete outputs: a score out of 100, the reason, the single highest-value change, and rule violations. It also distinguishes itself from the draft path by pointing at test_run_draft and edit_step, so an agent can tell it apart from 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?

It states exactly when to use it (to tell the person how the workflow did), what to do next (offer to fix, run edit_step, then test_run_draft), and which sibling to poll afterward (get_test_run until check.status is done). Explicit alternatives and a clear success path leave nothing to inference.

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