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

Annotations already declare readOnly, idempotent, openWorld and non-destructive, so the safety profile is covered. The description adds genuinely new behavioral context beyond that: worldwide coverage, any-language input, and the shape of the result set. It omits ambiguity handling, which matters for a geocoder that can return multiple candidates.

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 short lines, front-loaded with the transformation, then the decision cue, then a copy-pasteable example. No sentence is redundant.

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?

With no output schema, the description usefully enumerates the returned fields, and the annotations carry the risk profile, so an agent has what it needs to call the tool. The remaining gap is the undocumented `lang` and `limit` parameters, which leaves callers guessing on result count and language handling.

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 only 33%, so the schema documents `query` alone and leaves `lang` and `limit` bare. The description reinforces `query` semantics ('any language', the Grand-Place example) but says nothing about what `lang` controls or that `limit` caps candidate results, leaving two of three parameters unexplained in both schema and prose.

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 uses a precise verb+resource pairing ('Turns an address, a place name or a city into coordinates') and enumerates the returned fields (latitude, longitude, full address, type, country). The forward geocoding direction makes it plainly distinct from reverse_geocode, so an agent can choose between them without opening either schema.

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?

An explicit 'Use when' clause lists concrete downstream needs (map, distance, weather, places_near) and a worked example anchors the input format. It stops short of naming reverse_geocode as the when-not alternative, so the exclusion criterion is left implicit.

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