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

The annotations already declare write, destructive, and open-world behavior, and the description's '[WRITE — public]' tag and confirm requirement largely restate that. It adds little beyond the annotations and schema — no indication of what closing does to the issue state, whether the comment can be edited/deleted, or auth requirements.

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?

A single sentence with the write/public tag front-loaded, the primary action stated immediately, and the confirm requirement called out last. Nothing is wasted.

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 exists, but full schema coverage plus declarative annotations cover most of what an agent needs. The only remaining gap is the effect of the close flag on the issue's state and failure behavior, which the description does not surface.

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%, so every parameter (body, repo, close, number, confirm) is already documented in the schema. The description mentions the confirm gate and the optional close behavior, but adds no syntax or format detail beyond the schema; 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?

The description gives a specific verb and resource ('Post a comment on a GitHub issue or pull request') plus a secondary action ('optionally close the issue'), which cleanly separates it from github_create_issue and github_get_issue. It does not explicitly name a sibling it overlaps with, so it falls just short of 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?

It states a concrete precondition for use ('Requires confirm:true'), which is more than most write tools offer. It gives no exclusion or when-not guidance (e.g. when to prefer github_create_issue), so it is clear context without alternatives.

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