Reverse geocode

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It only says 'Find', which suggests a read-only lookup, but does not disclose coordinate system assumptions, failure modes (e.g., out-of-range values, no address found), or any network/rate-limit behavior.

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, front-loaded sentence delivers the essential information with no filler. Every word contributes to understanding the tool's purpose and input.

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 simple two-parameter tool with no output schema, the description is adequate but not complete. It implies the return value (an address) but does not explain the meaning of 'nearest' or address format, nor any error/edge-case behavior. Given the complexity, more detail would improve agent success.

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 0%, so the description must compensate. It merely says 'GPS coordinates', which adds little beyond the parameter names 'lat' and 'lon'. It does not specify format (e.g., decimal degrees), valid ranges, or precision requirements, leaving the agent to rely on common knowledge.

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 states a specific verb ('Find') and a clear resource ('nearest French address') with the input ('GPS coordinates'). It differentiates from the sibling 'geocode_address' by reversing the direction (coordinates → address), which is immediately clear to an agent.

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 implies the use case—given GPS coordinates, get an address—but provides no explicit guidance on when to prefer this over alternatives like 'geocode_address', nor any exclusions or prerequisites. The intended context is inferable but not stated.

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