swiss_postal_data

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It mentions 'free, no auth' (useful access info) but doesn't disclose any limits (rate limits, pagination, response format, or whether it returns all three data types together or separately based on filters). With zero annotations and no output schema, this is a notable gap.

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, tight sentence plus a two-word clause, making it concise and front-loaded. It efficiently states the resource and the access requirement without waste.

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 lookup tool with 100% schema coverage and zero required parameters, the description covers the essentials: what it fetches and access requirements. However, with no output schema and no annotations, it doesn't clarify whether output is a list or single object, how filters combine (AND vs OR), or whether partial matches are returned. Adequate but with room for improvement given the absence of structured metadata.

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%, meaning all three parameters (canton, postal_code, municipality) are described in the input schema with examples. The description itself adds no parameter-level detail beyond 'get Swiss postal codes, street names, and administrative divisions,' which loosely maps to the three filters. Baseline of 3 is appropriate since the schema handles the heavy lifting.

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: get Swiss postal codes, street names, and administrative divisions via the OpenPLZ API. It identifies the resource (Swiss postal data) and the API source. However, it doesn't explicitly differentiate from siblings like swiss_geo_identify_canton or swiss_transport_station_search, though the purpose is distinct enough.

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 notes 'free, no auth,' which sets expectations about access. However, it doesn't specify when to use this tool vs. alternatives like swiss_geo_identify_canton or swiss_geo_identify_municipality, which could also resolve location information. No explicit exclusions or alternative references are provided.

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