Github Update Pr

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

Annotations declare readOnlyHint=false, openWorldHint=true, idempotentHint=true, destructiveHint=false. The description adds valuable behavioral context beyond these: it states that only supplied fields are sent (partial update), and that labels are not included in the payload. This transparency helps the agent set correct expectations for field updates and the need for a separate label call. It doesn't contradict 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 tight and front-loaded: the first sentence immediately conveys the partial-update behavior, followed by a crucial note about labels and a pointer to conventions. No wasted words, and the structure leads with the most important operational detail.

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 output schema exists, return details are covered. The description adequately explains the partial-update semantics and the label exception, which are the main operational complexities. It could go deeper on error handling or specific field formatting, but for an 8-parameter tool with rich schema descriptions, this is largely sufficient.

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 coverage is 63%, so the schema already documents most parameters. The description adds the key semantic that all fields are optional and unchanged if omitted, which is essential for callers. It also clarifies the labels parameter behavior (not re-adding the 'mcp' label), which goes beyond the schema. This is meaningful added value.

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 verb ('Updates'), resource ('existing pull request'), and clearly contrasts with siblings like github_create_pr and github_update_pr_branch. It also differentiates itself by explaining what it does NOT do (labels), 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?

The description provides clear context: partial updates, and explicitly calls out that labels require a second call. It also directs to github_get_skill('pr-management') for conventions. While it doesn't enumerate all alternative tools, the mention of the label limitation and the partial-update behavior effectively guides when to use this tool instead of others.

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