lookup_language

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

With no annotations provided, the description carries the full burden of explaining behavior. It discloses the output shape ('[code, label] pair'), ordering ('likeliest first'), coverage ('every language Europass knows'), and a caveat about languages not accepted as a mother tongue. This is substantive and goes well beyond a bare lookup description.

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 concise and well-structured. The first sentence states the core purpose, and the second adds output format, ordering, coverage, and a relevant caveat. Every sentence earns its place without redundancy or padding.

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 one-parameter lookup tool with an output schema available, the description is complete enough. It covers what the query means, what the response looks like, how results are ordered, and an important validation caveat. No critical operational detail is missing.

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 single required parameter 'query' has 0% schema description coverage. The description clarifies that the query is a language name, which provides basic meaning, but it does not add detail on accepted formats, examples, or ambiguity handling. It partially compensates for the empty schema but leaves some semantics to inference.

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 tool's purpose: find Europass-recognised language codes from a language name. It specifies the verb ('find'), the resource ('language codes Europass recognises'), and the input ('a language you can name'), distinguishing it from sibling lookup_country and search_occupation tools.

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 implies usage: call this when you have a language name and need its code, and it notes coverage ('every language Europass knows'). However, it does not explicitly state when not to use it or name alternatives such as add_language_skill or validate_cv, leaving the routing somewhat implicit.

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