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

With no annotations, the description must carry the behavioral burden; it usefully discloses a 1 € per-code charge, payment from balance or x402, and a 24-month expiry for unretrieved codes. It still omits reversibility or refund behavior, authentication details beyond the schema, failure modes, and return format.

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?

Three short sentences front-load the purpose, cost/scope, and expiry. Each sentence adds necessary information with no padding.

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 paid reveal operation with no annotations and no output schema, the description covers cost, payment source, selection behavior, and expiry. It leaves return values, payment-failure behavior, and authentication details to the schema or inference.

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 50%: api_key is documented in the schema, while ids is not. The description compensates by explaining that ids selects specific codes and omitting it reveals all waiting codes, but it gives no id format details.

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 uses a specific verb, 'Reveal,' with the resource 'waiting codes,' and states the per-code cost. It does not explicitly contrast with sibling tools like list_codes, but 'waiting codes' and the charge make the purpose fairly distinct.

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?

It says 'Give ids, or nothing to reveal all waiting codes,' which clarifies call scoping but not when to choose this tool over list_codes or other code-related siblings. There are no explicit exclusions or alternative-routing instructions.

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