reverse_geocode

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

No annotations are provided, so the description carries full burden. It states the output (a place name) but does not mention error behavior, return format, or any side effects. Since this is a simple lookup, a basic description is acceptable, but it lacks detail about what exactly is returned or how invalid inputs are handled.

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?

Two sentences with no wasted words. The description is front-loaded with the action ('Returns a place name') and immediately gives the usage context. Perfectly concise.

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 tool with full parameter schema and no output schema, the description is nearly sufficient. It lacks detail on the output format (e.g., string vs. structured object), but given the simplicity and that the output is just a 'place name,' a 4 is fair.

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 the schema already provides clear descriptions for both lat and lon. The description adds only the phrase 'coordinate pair,' which does not enrich parameter understanding beyond what the schema already states. 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 returns a place name for a coordinate pair, using a specific verb and resource. It distinguishes from sibling geocode (forward geocoding) by emphasizing the direction (lat/lng to place name).

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?

Explicitly states the use case: 'Use this when you have lat/lng coordinates and need a human-readable location name.' This implies the alternative (geocode) is for the reverse direction, making the intended usage very clear.

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