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

Goes well beyond the readOnlyHint/openWorldHint annotations by disclosing that Facebook may block or rate-limit automated requests (503), that the tool draws on a public plugin rather than an authenticated API, and that billing is $0.002 USDC per successful call via x402 with failed calls free. That failure-cost and rate-limit information is exactly the behavior an agent needs before calling.

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-loaded with the payload returned, then the exclusion, then operational caveats. Every sentence carries information, though the payment-provider enumeration (Base, Solana or Arc) is slightly more detail than selection requires.

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 one-parameter read tool with an output schema, the description covers the return surface, what is out of scope, rate-limit failure mode, and pricing. An agent can decide whether to call it and interpret a 503 without further reference.

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% for the single 'page' parameter, and the description adds nothing about accepted formats (username vs. numeric page id) beyond what the schema already states. Baseline 3 applies when the schema carries parameter 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?

The description names the resource (Facebook Page profile) and the source (Facebook's public Page Plugin), then enumerates exactly which fields come back: page name, follower count, verified flag, page link. It also marks the boundary — posts and discussions are not returned — which is the main ambiguity against siblings like social_facebook_posts and social_facebook_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 exclusion of posts/discussions implicitly signals when not to use this tool, but no sibling is named and there is no explicit 'use X instead' routing or prerequisite guidance. Usage is inferable rather than stated.

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