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

Annotations already flag this as a non-read-only, non-destructive write. The description adds genuine context beyond that: an authenticated caller with write access is required, and the response shape {commentId} is disclosed despite no output schema. It omits side effects such as reviewer notifications or whether duplicate comments are permitted, so it is solid but not rich.

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?

Three short sentences, front-loaded with the action, then the prerequisite, then the return value. No filler or repetition of the title.

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 simple four-parameter write tool this covers the essentials: action, auth requirement, and return value in lieu of an output schema. It leaves gaps around failure modes (missing PR, insufficient permissions) and notification behavior that would matter to an agent deciding whether to call it.

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%, with all four parameters documented including the Markdown format for body. The description adds nothing about parameter meaning or valid values, so the baseline 3 applies.

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+resource ('Add a comment to a pull request'), which is unambiguous on its own. It does not differentiate itself from close siblings like merjax_comment_issue, merjax_edit_comment, or merjax_list_pr_comments, so it falls short of a 5.

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 only usage signal is the implicit one in the tool name and first sentence. There is no guidance on when to use this versus merjax_comment_issue (issue comments) or merjax_edit_comment, and no note that existing comments should be listed first or that edits go through a different tool.

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