Look up municipality and county

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It conveys a read-only lookup via the verb 'Find' and mentions official codes, but it does not specify what happens when both coordinate and address are supplied, whether the address must be within Norway, or any error behavior. The return format is also left unspecified, which is a notable gap since there is no output schema.

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 a single, concise sentence that front-loads the core purpose and then states the two accepted input forms. It contains no filler or redundant information, achieving maximum clarity per word.

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 lookup tool, the description is mostly adequate: it names the output (municipality, county, official codes) and the input options. However, it lacks some details such as precedence when both address and coordinate are provided, whether the address must be geocodable within Norway, and the exact response structure (especially given there is no output schema). These gaps are not severe but prevent full completeness.

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%, so the baseline is 3. The description adds value by explicitly stating 'Give either a coordinate or a free-text address,' clarifying the mutual exclusivity and reinforcing that a coordinate implies both latitude and longitude are required together. This goes beyond the schema's parameter-level descriptions and helps the agent construct valid calls.

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 operation: 'Find which municipality (kommune) and county (fylke) a location falls in,' and specifies input options (coordinate or free-text address) and data source (Kartverket). It is distinct from sibling tools like search_address, though it does not explicitly contrast itself with them, so it loses one point for lacking explicit differentiation.

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 provides no guidance on when to use this tool versus siblings like search_address or validate_address. It only explains how to provide input (either coordinate or address), not the conditions that would make this tool the right choice. No exclusions or alternatives are mentioned, leaving the agent without decision criteria.

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