reverse_geocode

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

With no annotations provided, the description fully describes the tool's behavior: it uses Nominatim, returns display name, structured address components, and OSM identifiers. However, it does not mention rate limits, terms of use, or what happens on error, which would elevate transparency further.

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?

The description is extremely concise and well-structured. It starts with a clear purpose statement, then lists parameters in a readable format. Every sentence adds value, and there is no redundancy or fluff.

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?

Given the tool's low complexity (2 required numeric parameters) and the presence of an output schema, the description is fully complete. It explains what the tool does, what it returns, and the data source, leaving no critical gaps for an AI agent to select and invoke the tool correctly.

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 carries the full burden. It clearly explains each parameter: lat and lon, indicating they are required and providing example values (e.g., 51.5). This adds significant meaning beyond the bare schema definitions.

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's purpose: 'Reverse geocode coordinates to a human-readable address.' It uses a specific verb-resource pair, distinguishes from sibling 'geocode' (forward geocoding), and provides concrete examples of output components.

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 mentions the underlying service (Nominatim, free, no key) and lists required parameters with examples. While it does not explicitly contrast with siblings like 'geocode', the differentiation is implicit due to the reverse vs. forward distinction. A slightly more explicit 'when to use' statement would push it to 5.

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