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

Annotations already declare readOnlyHint, openWorldHint, idempotentHint, and destructiveHint as false, providing a strong behavioral baseline. The description adds the 17 data blocks (income, employment, demographics, etc.), which goes beyond annotations by specifying the content scope and confirming it's a non-destructive read-only operation.

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 sentence with 15 words, front-loading the core purpose and listing the key data blocks concisely. Every word earns its place with no redundancy or fluff.

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 single-parameter tool with 100% schema coverage, read-only annotations, and an output schema present, the description is complete. It explains what the tool does, what it applies to, and what the output contains, without needing to detail return values since the output schema handles that.

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 100% with a clear description for the postal_code parameter, including an example. The description adds conceptual meaning by summarizing what data the tool returns (17 blocks), but doesn't detail each block, which is acceptable given the output schema exists.

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 'socioeconomic profile' and clearly identifies the resource 'Spanish postal code'. It lists 17 data blocks, which distinguishes it from sibling tools like entity_lookup or get_competitors, and the input schema confirms it takes a single postal code parameter.

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 states it's for a Spanish postal code and provides an example (28013 = Madrid Gran Vía), making the usage context clear. However, it doesn't explicitly say when not to use it or mention alternatives among the listed siblings, such as get_full_dossier for broader entity data.

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