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

With no annotations provided, the description carries the full burden of behavioral disclosure. It does reveal a key behavioral nuance: the obligation applies from a specific future date, and the tool returns legal responsibility and penalty ranges. However, it doesn't clarify whether the tool performs exhaustive checks or provides definitive legal advice, nor does it mention any input validation or edge cases.

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 highly concise, clearly front-loading the geographic scope and core purpose. Every sentence adds value: the first states the scope and purpose, the second lists the outputs. It is efficient and structured for quick comprehension, with no filler.

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 tool with no output schema, the description adequately summarizes the expected outputs (obligation, responsible party, penalty range, system requirements). However, it doesn't specify the exact format of those outputs (e.g., structured fields vs. prose), which could be important for an agent. Given the tool's complexity (5 parameters, 100% schema coverage), it is largely complete but could benefit from a note on edge cases (e.g., future date applicability).

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 description coverage is 100%, so all parameters are already described. The description does not add new meaning but reinforces that the tool is about how goods move. The parameter descriptions, especially for hires_carriers, already include explanatory notes about shipper duties. The description's reference to 'how it moves goods' does add a slight framing but is not essential.

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 what the tool does: determines DeCA obligation based on how goods are moved, and explicitly lists the outputs (obligation, responsible party, penalty range, system requirements). It specifies the jurisdiction (Spain) and effective date (5 October 2026), making it distinct from any generic compliance tool.

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 specifies the tool is for Spain only, giving a clear geographic context. However, it does not explicitly state when NOT to use it (e.g., outside Spain) or mention alternatives among siblings (like check_compliance_deadlines). It implies use for DeCA-related queries, but lacks explicit exclusion guidance.

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