ci__diagnose_run

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

Annotations cover read-only/idempotency, yet the description still adds substantial behavior: the default selection logic (newest FAILED/ERRORED, skipping canceled/skipped, within the newest 40 runs), that output contains failing actions/issues/tests, and that counts are bounded with truncation notes. That is materially more than the annotations provide.

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?

Front-loaded with purpose, then parameters, then default behavior, then return summary. Dense but every clause carries information; the nested parentheticals on run selection are the only mild density cost.

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?

Output schema exists, so return details need not be spelled out, yet the description summarizes them anyway. With annotations plus a complete schema, the definition gives an agent everything needed to call it correctly.

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 app, run, and workflow. The description restates them as a narrative and clarifies workflow's purpose ('to narrow the run search') and run's default, but adds little beyond the schema baseline.

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 (Diagnose) and resource (why an Xcode Cloud build failed), plus the value proposition 'in one call'. It is immediately distinguishable from the build-listing and build-detail siblings that only retrieve metadata.

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?

Gives clear context: supply an app identifier, optionally narrow by run/workflow, and by default the tool inspects the newest FAILED/ERRORED run. It does not name an alternative tool or exclusion condition, but no close sibling competes for the same job.

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