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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and closed-world, so the safety profile is covered. The description adds real context beyond that: it explains what class of defect is detected and why it matters ('a conversation behind the change that a later reader has no access to'). It does not describe the shape or granularity of the findings returned, which is a minor gap in the absence of an output schema.

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 defect class and then the actionable instruction. The inline examples of AI tells earn their place by making the detection criteria concrete rather than restating the name, though the middle explanatory sentence is slightly verbose.

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 read-only checker with no output schema, the description covers what it detects, why it matters, and when to call it. The only meaningful omission is any hint at what the results look like, but with annotations covering the safety profile and a single well-documented parameter, an agent has enough to invoke 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?

Single parameter at 100% schema description coverage, so the schema already carries the meaning. The description's 'source file or diff' mirrors the schema text without adding syntax, size limits, or format expectations, so baseline 3 is appropriate.

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: check a source file or diff for AI 'tells' in comments, with concrete examples of the patterns it hunts ('as requested,' 'I've added'). The scope is unambiguous and the domain differs obviously from check_copy and check_design, but the description never names or contrasts against those siblings, so it stops just short of full differentiation.

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 an explicit trigger: 'Call this before committing or shipping code an agent wrote,' which tells the agent both when and on what artifact to invoke it. It does not state when NOT to use it or offer any alternative sibling for adjacent review tasks, so no exclusions are covered.

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