Private reply to comment

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

Annotations already flag destructive/non-idempotent, and the description goes well beyond them: it discloses the single-attempt rule, 7-day window, irreversible Page-inbox delivery, lost-response ambiguity, and the pages_messaging/MESSAGING task requirements. No statement contradicts the annotations.

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?

Four tense sentences open with the core purpose, then hard limits, the irreversible-apply requirement, and retry/authentication caveats. There is no filler and no repetition of schema details.

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 destructive, non-idempotent mutation with no output schedma, the description covers prerequisites, one-time limits, irreversibility, and retry behavior. It does not spell out the response/planId shape, though the apply parameter description partially fills that gap, so a small completeness gap remains.

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?

Al six parameters are fully documented in the schema, so the baseline is 3. The description adds operational meaning beyond the schema by stating that a real send always requires apply:true plus a plan_id from a dry run, and that blindly retrying after a lost response is unsafe.

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 action and resource — sends a private message to the author of a comment — and the 'private' qualifier distinguishes it from sibling facebook_reply_to_comment. The one-per-comment and 7-day limits further pin down what this tool is for.

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?

The description gives clear context: use it for private one-off replies to comment authors, with hard limits and a required dry-run + apply flow. It does not explicitly name alternatives or state when not to use it, so it falls short of full alternative-routing guidance.

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