Comment on post

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

Goes well beyond the annotations by disclosing the PUBLIC visibility of the comment, that it is reversible via deletion, that it is NOT idempotent with a concrete double-post risk and recovery path, and that @[page-id] mentions are subject to Facebook review. The one omission is that it never mentions the apply/plan_id dry-run behavior, so a description-only reader could believe a call always writes — the schema carries that, but it is a notable behavioral gap for a write tool.

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?

Front-loads the action and scope, then packs alternatives, idempotency warning, and auth requirements into four tight sentences with no filler. Dense but every clause carries decision-relevant information.

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?

Covers the alternative tool, idempotency, reversibility, auth scopes, and content constraints for a 6-parameter write tool with no output schema. The remaining gap is the dry-run/apply-first default, which is fully documented in the schema but absent from the description.

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 the baseline is 3; the description earns above that by adding the real constraint that `message`, `attachment_url`, or both are needed (the schema only requires `post_id`), by clarifying the attachment is an https image Facebook fetches itself, and by noting mention pass-through semantics.

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 and resource ("Post a PUBLIC top-level comment as the Page on a post") plus the scope distinction that matters most: top-level vs. reply. It names the sibling to use for the other case, so an agent can disambiguate from facebook_reply_to_comment without opening either schema.

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?

Explicit routing: "To answer a comment use facebook_reply_to_comment instead." It also gives a concrete recovery procedure (verify with facebook_list_comments before retrying) and the exact permission/task requirements, which is when-to-use guidance at the operational level.

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