Search Address (Spain)

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

No annotations are provided, so the description carries the full burden. It discloses geographic coverage limits, the expected input shape, and the downstream chaining step, but says nothing about behavior on no-match, partial-match, rate limits, or authentication, which would matter for a lookup tool.

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?

Front-loaded with purpose, then constraints, then required inputs, then next step. The two inline examples consume space but are directly useful for formatting the free-text input; no sentence is 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 single-parameter lookup with no output schema, the description covers input format, geographic scope, and the follow-up call well enough to invoke correctly. It stops short of describing failure modes or what the returned reference looks like in structure.

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 coverage is 100% so the baseline is 3, but the description adds real value beyond the schema by giving two concrete format examples and the instruction to include street number and municipality or postal code. It slightly exceeds the schema's terser field note.

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?

States a specific verb+resource ('Find the Spanish cadastral reference for a postal address') and explicitly scopes it to free-text Spanish addresses. It clearly distinguishes itself from the sibling get_parcel by describing the address-based path versus the coordinate-based path.

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?

Explicitly states when to use it (Spanish postal address as free text, Spain central Catastro), when not to (Basque Country, Navarre, other countries), what the alternative is ('use get_parcel with coordinates there'), and the required follow-up ('call get_parcel with the returned reference and country ES').

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