Create pull request

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

Annotations already declare readOnlyHint=false, destructiveHint=false, and openWorldHint=true, so the safety profile is covered. The description adds useful behavioral detail about cross-repo forks via `owner:branch`, but does not mention auth needs, rate limits, or downstream effects such as notifications or webhook triggers.

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 core action and no filler. The second sentence is a useful edge-case note, though the overall brevity is slightly aggressive for a 9-parameter write tool.

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 9-parameter mutation tool with 22% schema coverage and no output schema, the description omits required title, body usage, labels/assignees/milestone, return behavior, and permission considerations. It covers only the head/base relationship and leaves major gaps.

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 only 22%; only owner and repo have schema descriptions. The description clarifies head/base direction and cross-repo head format, but leaves required title, body, labels, assignees, and milestone semantics unexplained, so it fails to compensate for the low 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?

States a specific verb and resource: 'Open a pull request from `head` into `base`.' This clearly separates it from read/update/merge sibling tools, but it does not explicitly name or differentiate from close alternatives like update_pull_request or create_pull_request_review.

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?

No when-to-use guidance, prerequisites, or alternatives are given. The description implies creation via 'Open' but does not say when to use this versus update_pull_request, merge_pull_request, or when a PR is inappropriate.

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