Update PR

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

The description adds critical behavioral detail beyond annotations: omitted fields are left unchanged, description is Markdown, and reviewers replace the full list including the UUID curly-brace format. These are non-obvious traits that significantly aid correct invocation.

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?

Four concise sentences with the purpose front-loaded. Every sentence delivers operational value—no filler or redundancy.

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 6-parameter optional-input tool without an output schema, the description captures all essential behaviors: partial updates, Markdown handling, and reviewer replacement semantics. It doesn't discuss response/error details, but that is less critical for an update tool.

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?

With 100% schema coverage, the baseline is 3, but the description adds global semantics like 'fields you omit are left unchanged' and 'pass an empty array to clear all reviewers,' which enrich the meaning of omitted and empty values. This elevates it above the baseline.

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 opens with 'Update a pull request's title, description (the PR Overview), and/or reviewers,' clearly identifying the action and the specific resource fields. This distinguishes it from sibling tools like get_pr (read-only) and create_pr.

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 states 'Pass any combination — fields you omit are left unchanged,' which gives a clear usage rule. It doesn't explicitly mention alternatives, but the partial-update semantics are a strong contextual signal for when to use this tool.

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