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

The annotations already declare this tool as readOnlyHint=true, openWorldHint=true, idempotentHint=true, and destructiveHint=false. The description largely reinforces the read-only nature by describing it as a 'profile', but it does not add behavioral context beyond the annotations. For example, it doesn't mention the size of the response (the output schema exists), or any potential limits on calls, which would add value.

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, tightly packed sentence that communicates the core function and scope. It efficiently lists the key data domains without unnecessary elaboration. Every part of the sentence earns its place, and the information is front-loaded with the primary verb 'Socioeconomic profile'.

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?

Given the tool has a single required parameter with full schema coverage and an output schema exists, the description is minimally adequate. It explains what the tool does and what you need to provide. However, for a tool that outputs 17 blocks of data, it could be more helpful by briefly summarizing a few typical use cases or clarifying the breadth of each block (e.g., 'real estate' could mean house prices vs. construction permits). The output schema might cover this, but the description doesn't lean into 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 schema has 100% description coverage for the single parameter 'postal_code', including the pattern and an example. The description adds context by stating the tool is for Spanish codes, which reinforces the schema's Spanish designation. Since coverage is high, a baseline of 3 is justified; the description adds a concrete example, pushing it to a 4.

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 provides socioeconomic profiles for Spanish postal codes, listing 17 specific data blocks (income, employment, etc.). This gives a strong and specific sense of the tool's purpose, though it doesn't explicitly differentiate it from its siblings, particularly 'entity_lookup' or 'get_full_dossier', which might have overlapping geographic 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 implicitly defines usage context: when you need socioeconomic data for a Spanish postal code. It includes a realistic example (28013 = Madrid Gran Vía) that aids selection. However, there is no explicit guidance on when *not* to use it (e.g., if you need a broader region) or alternatives among the listed siblings, which would have earned a 5.

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