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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint. The description adds genuine value beyond that by stating it is free and covers all paid endpoints, but says nothing about rate limits, caching, or freshness of the returned schemas.

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?

A single sentence with zero waste, and the cost-relevant qualifier 'Free' is front-loaded so an agent sees the pricing fact immediately.

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?

An output schema exists, so return-value detail is unnecessary. For a zero-parameter discovery tool whose safety profile is covered by annotations, the description supplies everything an agent needs to select and call it.

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?

The input schema has zero parameters and full coverage, so the baseline applies. The description adds nothing parameter-related because there is nothing to parameterize.

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?

A specific verb ('request') plus concrete resource list ('schemas, examples, prices and limits for every paid tool/endpoint'), which implicitly distinguishes it from the sibling paid endpoints. It is clear what the tool returns, though it never names a sibling directly.

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?

Usage is only implied: by describing itself as free metadata for the paid tools, an agent can infer it should be called before invoking a paid sibling. There is no explicit 'call this first' instruction or when-not guidance.

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