Convert an address or place into coordinates, or reverse-geocode longitude and latitude into a readable address using a keyless Esri world geocoder.
Geocode an address/place to coordinates, or reverse-geocode a coordinate to an address.
Esri public world geocoder — no key required. Reverse mode: pass lon and lat.
| Name | Required | Description | Default |
|---|---|---|---|
| lat | No | ||
| lon | No | ||
| max_results | No | ||
| single_line | No |
| Name | Required | Description | Default |
|---|---|---|---|
| result | Yes |
Changes observed during successful MCP inspections.
v0.12.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full behavioral burden. It usefully discloses that this is an Esri public world geocoder and that no key is required, but it does not mention rate limits, error behavior, or how result limits 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?
The description is three short sentences and is front-loaded with the primary purpose. The reverse-mode note follows logically and every sentence adds useful information without waste.
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?
The output schema is present, so return values need not be explained. But with no annotations and 0% schema coverage, the description is incomplete: it omits the forward-geocoding parameter and the meaning of `max_results`, leaving an agent with insufficient guidance for a four-parameter tool.
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 explain the four parameters. It documents reverse-mode `lon` and `lat`, but leaves `single_line` and `max_results` unexplained, including the forward geocoding input path.
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 and resource: geocode an address/place to coordinates, or reverse-geocode a coordinate to an address. It clearly separates the two modes and names the provider, making the tool distinct from the search/query/map siblings.
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?
It gives a mode-specific instruction for reverse geocoding: pass `lon` and `lat`. However, it does not explain when to use this tool versus alternatives such as `arcgis_request`, nor does it clarify how forward geocoding should select the appropriate input parameter.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.