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

Annotations already declare this is a non-destructive write (readOnlyHint=false, destructiveHint=false, openWorldHint=false). The description adds useful context beyond that: the comment is surfaced to the team in the dashboard issue thread and markdown is supported. It stays silent on return values, editability/deletion of comments, and error behavior, so it adds moderate value rather than rich behavioral detail.

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?

One sentence for purpose and audience plus a four-word note on formatting; zero filler and the action is front-loaded.

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 three-parameter write with full schema coverage and safety annotations, the description covers what is being created and who sees it. Given no output schema exists, a brief note on the response or failure modes (e.g. invalid issue number) would make it fully complete.

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% and all three parameters are documented, including that issue_number comes from list_issues and that body is markdown. The description only restates the markdown support already in the schema, 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?

The description opens with a specific verb and resource ('Post a comment on a website issue') and then enumerates the concrete purposes (analysis, proposed fix, changelog note), which makes it unmistakable next to read-oriented siblings like get_issue and list_issues.

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 clearly states when to use the tool ('to record analysis, a proposed fix, or what you changed'), giving an agent good context for intent. It does not, however, rule out alternatives or mention prerequisites such as needing an existing issue, so it stops short of explicit when-not guidance.

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