update_pull_request_tool

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

With no annotations provided, the description must carry the burden of behavioral disclosure. It does disclose a key non-obvious behavior (does not merge) and gives a concrete example of closing. Yet it omits other relevant behaviors like whether changes are reversible, permission requirements, or effects on CI/notifications. The description adds some value but is not extensive.

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 concise at two sentences, with the core purpose stated first and the critical 'not merge' caveat immediately following. It avoids redundancy and front-loads the most important information, making it easy for an agent to parse quickly.

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?

Given the tool's complexity (6 parameters, mutation behavior) and absence of annotations, the description covers only the essential distinction (no merge) but lacks details about side effects, partial updates, or error conditions. Since an output schema exists, return-value explanation is not required, but operational context is thin. This is adequate but not fully thorough.

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 each parameter is already documented. The description does not add new semantic meaning beyond the schema; it only reiterates the state parameter's purpose. According to the calibration, baseline 3 is appropriate when the schema covers parameters fully.

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 the tool updates a GitHub pull request and explicitly includes closing or reopening as capabilities. It distinguishes itself from merging, which a sibling tool might handle, and the verb 'update' with the resource 'pull request' is specific and 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?

The description provides a clear 'do not' for merging ('This does NOT merge') and explains how to close a PR without merging. However, it does not explicitly state when to use this tool versus alternatives, nor does it mention any prerequisites or conditions for reopening. The guidance is helpful but minimal.

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