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

Annotations already declare readOnlyHint, openWorldHint and idempotentHint, so the safety profile is covered. The description adds real context beyond that: the primary data source (swisstopo address register) with an OpenStreetMap fallback, and the geographic coverage limit that implies non-Swiss/German addresses are unsupported. It does not disclose failure behavior or result accuracy.

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?

A single dense sentence that front-loads the action and scope and ends with the return fields and sources. No filler or redundancy.

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?

With no output schema, the description usefully names the returned fields and the source hierarchy, and annotations cover the safety profile. It stops short of describing what happens for ambiguous or out-of-region addresses, which an agent invoking an open-world geocoder would benefit from knowing.

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% and there is a single required parameter already documented with constraints (3-200 chars) and an example in the schema. The description adds only the implicit geographic constraint on the address value, so the baseline 3 applies.

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 ('Resolve'), a specific resource (Swiss or German street address), and the exact outputs (latitude, longitude, postcode, country), plus the underlying data sources. This is unambiguous and clearly distinguishable from siblings like list_cities and solar_first_estimate.

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 geographic scope ('Swiss or German') implicitly tells the agent when this tool applies and when it may fail, but there is no explicit when-to-use statement or named alternative for out-of-scope geocoding needs. Usage is inferable from the single obvious purpose rather than stated.

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