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

Annotations already declare readOnlyHint=true and openWorldHint=false, so 'Read-only' is redundant. 'Rate-limited per domain' is genuinely new behavioral information beyond the annotations, but gives no magnitude, backoff guidance, or throttling error behavior, and nothing is said about auth or failure modes.

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?

A single dense sentence: resource and scope first, then the differentiating diagnostic purpose, then the read-only/rate-limit caveat. No filler, nothing buried.

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?

No output schema exists, so the description should hint at returns; it implies raw log text but does not describe format or ordering. For a 3-parameter read tool with annotations covering safety and a fully documented schema, this is nearly complete, with only the return shape left implicit.

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% (lines default 200, since default 60, project_uuid source noted), so the schema carries the parameter burden. The description adds no meaning about the parameters — no guidance on picking line counts or time windows for a deploy failure — so baseline 3 applies.

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?

Specific verb+resource ('Fetch recent Cloud Run logs for a project's deployed app') with an explicit scope statement that separates it from deployment/status siblings: 'THE tool for diagnosing a failed/stalled cloud deploy or a crashing app.' Names concrete failure symptoms (startup-probe timeouts, tracebacks, PORT errors), so an agent can match a problem to this tool without opening the 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?

Gives a clear use context with concrete diagnostic symptoms, which is more than most definitions offer. It does not name alternatives (e.g., build_deploy_status, build_doctor) or state when not to use it, but the symptom list functions as a strong positive selector.

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