GitHub MCP Server

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It states the tool creates a comment, implying a write operation, but does not disclose any behavioral traits such as required permissions, whether the comment is editable/deletable, rate limits, or how it integrates with GitHub's review workflow. This leaves significant gaps for an agent to understand the tool's behavior beyond the basic action.

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 a single, clear sentence that directly states the tool's purpose without any unnecessary words. It is front-loaded and efficiently conveys the core action, making it easy for an agent to quickly understand what the tool does.

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 complexity of 11 parameters (6 required) and no annotations, the description is minimal but adequate as a starting point. However, it lacks details on behavioral aspects like permissions or workflow integration. The presence of an output schema means the description does not need to explain return values, but it could benefit from more context to fully guide usage in a GitHub review scenario.

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?

The input schema has 100% description coverage, with each parameter well-documented in the schema itself (e.g., 'owner' as 'Repository owner', 'line' as 'The line number in the diff to comment on'). The description adds no additional meaning beyond the schema, such as explaining parameter interactions or constraints, so it meets the baseline score of 3 where the schema does the heavy lifting.

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 action ('Create a review comment') and the target ('on a specific line of a pull request diff'), which is a specific verb+resource combination. However, it does not explicitly distinguish this tool from sibling tools like 'create_issue_comment' or 'create_pr_review', which are related but serve different purposes in GitHub's review system.

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 no guidance on when to use this tool versus alternatives. It does not mention sibling tools like 'create_issue_comment' (for general issue comments) or 'create_pr_review' (for overall PR reviews), nor does it specify prerequisites or exclusions, such as requiring review permissions or being applicable only during code review processes.

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