github_get_pull_request_checks

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

Annotations indicate readOnlyHint=false, destructiveHint=false, and idempotentHint=false. The description adds valuable context by explicitly stating that it appends evidence (a write side-effect) and requires the PR number and head SHA to match for review runs. This goes beyond the annotation flags and explains real behavioral constraints. No contradiction with annotations.

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 two sentences with no redundant words. It front-loads the primary action and side-effect, then gives usage context and a critical condition. Every sentence earns its place—concise without sacrificing essential guidance.

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 tool with 3 required parameters and no output schema, the description provides sufficient context: what it does, when to use it, and a key prerequisite. It doesn't cover error handling or response format, but these are not required when the action and constraints are clear. The detail about the head SHA matching is especially valuable for correctness.

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 three parameters are well-documented in the schema itself. The description does not add new parameter-level detail, but it does reinforce that pullNumber must correspond to a live PR ('the PR number and current head SHA must still match the run'). This aligns with the schema's exclusiveMinimum and maximum. Baseline 3 is appropriate given full schema coverage.

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 states a specific action ('Read GitHub combined commit statuses and Actions check runs for a pull request') and its side-effect ('then append the result as ci_result evidence'). This clearly identifies the tool's purpose and distinguishes it from siblings like github_get_pull_request (fetches PR metadata) and github_list_pull_request_files (lists changed files).

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?

The description provides clear usage context: 'Use during verification or read-only review after a PR exists.' It also includes a precondition: 'For review runs, the PR number and current head SHA must still match the run.' Though it doesn't explicitly name alternatives, the timing and conditions are unambiguous. A small deduction for not explicitly saying 'when not to use'.

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