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

Annotations already establish this is a non-destructive write (readOnlyHint=false, destructiveHint=false, openWorldHint=false). The description adds a concrete behavioral constraint not present in annotations: a 60-per-hour rate limit, which matters for an agent that may loop. It doesn't explain auth or error behavior, but the rate limit is genuine added value.

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 short sentences, with the core action front-loaded and the constraint immediately after. No filler.

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 two-required-parameter write tool with full schema coverage, no output schema needed, and annotations covering the safety profile, the description plus rate limit is nearly sufficient. Only auth nuance and failure modes are absent.

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%, so all three parameters (id, body, api_key) are fully documented in the schema, including the 2000-character body limit and the API-key alternative. The description adds nothing about parameters, so the baseline of 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 (add) and resource (comment on a feed post), which is clearly distinct from react_to_post and create_post. It does not explicitly name siblings, but the action is unambiguous.

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?

No guidance on when to use this versus react_to_post or create_post, and no prerequisites such as needing a valid post id or auth context beyond the schema. Only a rate limit is given.

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