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

Annotations cover the safety profile (readOnly, openWorld, non-destructive), and the description goes well beyond them: it discloses that a station name yields a same-named district (one in Potsdam) and that the returned id is an OSM id, not a drivable stop id. It also explains the score matching semantics (1 = exact, >=0.5 whole word) and adds an anti-fabrication instruction about only using returned names and ids.

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 the core purpose, then the critical exclusion, then parameters, then the usage guide and anti-fabrication note, with bold markers making sections scannable. It is dense rather than padded, but the single block is long and some parenthetical examples could be trimmed without loss.

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 read-only lookup with no output schema, it covers purpose, alternatives, required/optional params, matching behavior and what the returned id actually is. It stops short of describing the full response shape (e.g. whether coordinates and ids come as a list of candidates), so an agent still infers some of the return 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 description coverage is 100%, so a 3 is the baseline. The description adds real signal on top: it restates name as mandatory and clarifies that lang has no current effect (the schema only says "advisory"), which is a genuine refinement. The format parameter is left to the schema and the reference to a `score` field is a bit ambiguous, keeping it from a full 5.

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 precise verb and resource: it resolves the NAME of a city, region or district into coordinates and OSM-Ids, and frames this as the first step for locating an area. It actively distinguishes itself from siblings by naming reverse_geocode and nearby for their respective jobs, so an agent can route without opening any schema.

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?

Gives explicit when-to-use (locating a region/city for questions like weather or activities) and explicit when-NOT-to-use (any request containing Bahnhof/Hbf/Bf or any stop/address/POI that could be a journey endpoint, which belongs to resolve_location). Concrete examples ("Köln Hauptbahnhof", "Hannover Bahnhof") show what goes wrong otherwise, and it points to get_usage_guide for deeper chaining.

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