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

Beyond the read-only and open-world annotations, the description discloses the per-call maximum, that commenter names and handles are omitted, and the pay-per-call stablecoin/refund model. It still does not cover pagination, ordering, or deeper access constraints, but it adds substantial behavioral context.

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?

The description is compact and front-loaded around the core action, then adds only high-value details: returned fields, limits, privacy behavior, and payment terms. Every sentence earns its place.

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?

With no output schema, the description usefully lists the returned comment fields and states that commenter identities are excluded. It is mostly complete for invoking the tool, though it could say more about pagination, ordering, or whether more than 100 comments are retrievable across calls.

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 both the url and limit parameters are already documented in detail. The description repeats that it accepts public post/video/reel URLs and mentions the 100-comment cap, but adds little parameter semantics beyond the schema.

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 states a specific verb and resource: fetching comments for a public Facebook post, video, or reel URL. It clearly distinguishes this from Facebook content-fetching siblings such as facebook-posts or facebook-page by focusing on comments.

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 use case is strongly implied—send a public Facebook URL to get its comments—but the description does not explicitly say when to use this instead of facebook-posts, facebook-page, or other comment tools. No exclusions or alternative-routing guidance are provided.

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