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

There are no annotations, so the description carries full responsibility for disclosing behavior. It does not mention read-only nature, error handling, rate limits, or what happens for invalid codes. The only extra hint is 'see series.txt' for valid codes, but this is not elaborated.

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, front-loaded sentence with no wasted words. It immediately states the purpose and references the series list, making it efficient for quick scanning.

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 simple one-parameter read tool, the description is minimally adequate. It tells the agent the purpose and points to a code list, but it does not describe the return format, whether multiple values are returned, or error behavior. Given no output schema, these gaps remain unresolved.

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 0%, so the description must compensate. It explains that the parameter 'code' identifies an INE series and points to series.txt for valid values. This adds meaning beyond the schema's bare type declaration, though it does not specify format or value constraints in detail.

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 clear, specific action: retrieving the latest values of one INE series by code. It names the resource (INE series) and the key parameter (code). It distinguishes from siblings because they cover BOE and tenders, so there is no ambiguity about which tool to use for INE data.

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 no explicit guidance on when to use this tool versus alternatives. While the siblings are clearly different domains (BOE, tenders), it does not state conditions or exclusions. It only implies usage for INE series data, leaving the agent to infer context.

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