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

The readOnlyHint annotation already signals a safe read operation, lowering the burden on the description. The description adds useful context about the official data source (PLACSP) and the nature of the returned data, but does not disclose pagination behavior, ordering, or any other operational traits beyond what annotations and schema already imply.

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 a single, focused sentence that front-loads the core purpose and includes the source and output fields without unnecessary words. Every part contributes to understanding the tool.

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 an output schema present and readOnlyHint annotation, the description does not need to explain return values or safety. It clearly identifies the source and content, though it omits pagination details. The cursor parameter is at least partially described in the schema, so the overall picture is adequately complete for a read-only list tool.

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 only 33%, covering only 'cursor'. The description does not explain the required 'empresa_id' parameter or the meaning of 'limit', relying entirely on the parameter names and schema metadata. Since the schema is mostly undocumented, the description should have compensated but does not.

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 clearly states the tool's function: public contracts awarded to a company, with an official source (PLACSP). It enumerates the specific data returned (órgano de contratación, expediente, importe, fecha, link), making it easy to distinguish from sibling tools like subvenciones_empresa or cuentas_anuales.

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 provides clear context for when to use this tool: when you need public contract awards for a company. It does not explicitly exclude alternatives or name sibling tools, but the domain is specific enough that an agent can infer when it applies, especially alongside sibling names.

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