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

Annotations already declare readOnlyHint=false and destructiveHint=true, so the safety profile is covered. The description adds verdict semantics and explains request/cancel_request, but is silent on the destructive 'delete' and 'dismiss' actions and whether those are reversible — a gap the annotations flag but do not explain.

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?

Two sentences, front-loaded with the resource scope, no filler. Efficient and well-ordered, though it could consolidate the action list rather than covering only a subset.

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 13-parameter, nine-action tool with no output schema, the description covers only a few actions and omits the behavior of get/list/submit/dismiss/delete. Given the complexity, an agent must rely on the schema alone for most operations, which is adequate but not complete.

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 all 13 parameters are already documented in the schema, including the enum action. The description's mention of verdict values (APPROVED, REQUEST_CHANGES, COMMENT) merely restates what the schema already provides, 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 specific resources (PR reviews, review comments, review requests) with concrete operations, and names verdict values. It doesn't distinguish itself from the sibling 'comments' or 'pull_requests' tools, leaving some ambiguity about which handles which comment type.

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?

Provides action-level guidance for 'request' (ask users/teams to review) and 'cancel_request' (withdraw), which is useful. But it gives no guidance on when to use this tool versus the sibling 'comments' or 'pull_requests' tools, and six of the nine actions (get, list, submit, dismiss, delete, list_comments) get no guidance at all.

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