geo_get_departement

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

The description adds the conditional behavior 'including its region when available,' which is useful context beyond the schema. With no annotations, it does not disclose error handling for unknown codes or explicitly confirm it is read-only, but for a simple getter this is a modest gap.

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 very short, front-loads the core behavior, and contains no filler. The Args section efficiently communicates the parameter meaning and examples.

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 one-parameter getter with an output schema, the description covers what is returned, how to specify the department, and the region condition. It lacks a note about unknown-code behavior, but the tool's simplicity and output schema reduce the need.

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?

The schema only declares code as a string, so the description's 'Official department code' with examples '13, 75, 2A' adds essential formatting and domain meaning. It compensates well for the 0% schema coverage on the single parameter.

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: 'Return one department by code' and mentions the region inclusion. It implies a distinct exact-code lookup compared to sibling search tools, but it does not explicitly name or contrast itself with geo_search_departements.

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 phrase 'by code' clearly implies this tool is for callers who already have an official department code. However, it gives no explicit guidance about when to prefer a search sibling or when this tool should not be used.

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