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

Discloses read-only nature and free cost, which are helpful beyond missing annotations. Does not mention rate limits, data source usage policies, or potential limitations, leaving some behavioral traits opaque.

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 concise, front-loaded sentences. Every word adds value: action, resource, data source, safety, cost. No 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?

For a simple two-parameter tool with no output schema, the description covers purpose, data source, and cost. Missing only a hint about return value format, but overall adequate.

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% with descriptions for lat and lon already provided. The description adds no extra meaning beyond what the schema offers.

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?

Clearly states it reverse-geocodes a lat/lon coordinate to nearest address/place via OpenStreetMap Nominatim. Verb 'Reverse-geocode' and resource are specific, and it naturally distinguishes from sibling geo_intel_geocode.

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?

Purpose implies usage for reverse geocoding, and notes it is read-only and free. However, it does not explicitly state when to use vs alternatives like geo_intel_geocode or provide exclusions.

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