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

Annotations already declare readOnlyHint, openWorldHint, idempotentHint, and non-destructive behavior. The description adds valuable behavioral details beyond annotations: it uses OpenStreetMap Nominatim, is limited to Sweden, and returns up to 5 candidates with name, lat, and lon. This gives the agent a realistic expectation of external dependency and result limits.

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?

Three sentences with no filler: purpose, external source and scope, result count and fields, and a direct downstream usage instruction. Every sentence earns its place and the key limitations are front-loaded.

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 read-only tool with full schema coverage, annotations, and an output schema, the description covers all necessary operational details: geographic scope, external service, result format, and a usage path. Nothing critical is missing.

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%, and the schema already provides a clear description and examples for the query parameter. The tool description adds the context that query can be a city, town, or street address, but this mostly restates schema content rather than providing new semantic depth. Baseline 3 is appropriate.

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 the tool searches for a Swedish place and returns matching coordinates, with a specific verb and resource. It distinguishes itself from sibling tools like search_shelters by focusing on geographic locations, not shelters.

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 provides clear context: it searches Swedish places and explicitly instructs to use the resulting coordinates with find_nearby_shelters. It does not explicitly exclude alternatives, but the downstream usage guidance is sufficient for correct selection.

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