list_municipalitiesList municipalities for a given state (UF). Returns each municipality with its 7-digit IBGE id and name. e.g. uf="RJ" lists all municipalities in Rio de Janeiro.
| Name | Required | Description | Default |
|---|---|---|---|
| uf | Yes | 2-letter state code, e.g. "SP", "RJ", "BA", "MG". |
Changes observed during successful MCP inspections.
Input schema / examplesAdded value: +[
+ {
+ "uf": "SP"
+ },
+ {
+ "uf": "RJ"
+ }
+]Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already provide readOnlyHint, idempotentHint, and destructiveHint. The description adds return format and examples but no additional behavioral traits (e.g., pagination, rate limits). Since annotations cover safety, the description adds modest value beyond them.
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 two sentences, front-loaded with the main action, and includes a helpful example. No extraneous words. Highly concise and structured.
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 simplicity (one parameter, no output schema), the description fully covers what the tool does and returns. No additional context is necessary.
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%, providing clear parameter description. The description adds an example ('uf="RJ"') but does not significantly enhance meaning beyond the schema. Baseline 3 is appropriate.
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 verb 'List', resource 'municipalities', and constraint 'for a given state (UF)'. It specifies the return values (7-digit IBGE id and name) and distinguishes from siblings like list_states and lookup_municipality.
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 does not explicitly state when to use this tool versus alternatives. The example and mention of UF imply usage, but no when-not or alternative tools are mentioned. Includes a comparison threshold but not full guidance.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
Add one secure layer between your agents and this server.