create_comment

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

No annotations provided, so description carries full burden. Discloses return behavior (returns comment with `id`) and that `body` supports Markdown. Does not mention auth requirements, rate limits, or side effects beyond creation. Adequate but not comprehensive.

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: first covers action and key parameters, second explains return value and follow-up. No fluff, front-loaded with most important info.

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?

No output schema, but description explains return value (comment with `id`). Covers required parameters and defaults. Does not mention error cases or issue existence requirement, but provides enough for typical use.

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 100%, but description adds meaning: clarifies `index` as issue number, emphasizes `body` is required and supports Markdown, and hints at default values for `repo` and `owner`. Schema for `body` just says 'Comment body', so Markdown detail is extra 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?

Clearly states the action: 'Add a comment to an issue by its `index`.' Specifies resource (comment to an issue) and key parameters (`index`, `body`). Distinguishes from siblings by advising to retain the `id` for later `update_comment`/`delete_comment`.

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?

Describes when to use the tool (add a comment), notes that `body` is required and supports Markdown, and provides follow-up guidance (retain `id` for updates/deletes). Lacks explicit when-not-to-use or warnings about prerequisites, but sibling differentiation is hinted.

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