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

With readOnlyHint, idempotentHint, and destructiveHint already set, the description adds value by disclosing performance and quota behavior: 'Much cheaper and faster than a full re-review; does NOT consume review quota.' This is beyond the annotations and helps the agent choose cost-effective actions. No contradiction.

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 description is three sentences, each earning its place: purpose, benefit, and usage instruction. It is front-loaded with the most critical info and avoids unnecessary detail. Highly concise and well-structured.

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?

The description is sufficient for its complexity: an output schema exists (though not shown here), and the tool's purpose is simple. It covers when to use, key benefits, and what it returns. It doesn't detail the output format, but the output schema handles that. Overall, complete enough for an agent to invoke 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% per context, and the schema itself provides detailed descriptions for both parameters (files and issues) and their nested properties. The description adds minimal parameter-specific info beyond the schema (it doesn't explain each param), but it does clarify the relationship (e.g., 'same paths as the original review' is already in schema). Given high coverage, 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?

The description clearly states what the tool does: 'Re-check previous review_files findings against updated file contents. Returns fixed vs still-present per finding.' It distinguishes itself from siblings by emphasizing it's cheaper and faster than a full re-review and doesn't consume review quota, making its purpose unambiguous.

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 explicitly says 'Use after applying fixes,' indicating when to use. It also notes cost and quota advantages over a full re-review, implying it should be preferred in that scenario. However, it doesn't provide explicit exclusions (e.g., when not to use) or mention alternatives by name, but the context is clear enough.

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