List supported languages

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

With no annotations, the description carries the full burden, and it does so well. It discloses the endpoint, the structure of each entry (code, name, target codes), and the important behavioral fact that the list reflects the instance configuration rather than the client. It does not discuss errors or auth, but for a simple read-only list this is adequate.

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?

Three sentences, each earning its place. The first states the action and scope, the second describes the return data, and the third provides the critical configuration-dependent nuance. No filler or redundancy.

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 parameterless list operation with no output schema, the description is complete. It tells an agent what the tool does, what each result contains, and how to interpret missing entries. Nothing essential is missing for correct invocation.

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 tool has zero parameters, so the baseline is 4. The description adds useful detail about the result entries and the meaning of target codes, which compensates for any ambiguity in an empty input schema.

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 uses a specific verb ('List') and resource ('languages'), and clarifies the scope to a self-hosted LibreTranslate instance. It also implicitly distinguishes itself from the sibling tools translate and detect by being the only listing operation.

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 clear context for when this is useful: to determine which languages the instance supports and which target codes are valid. It implies that a language missing from this list cannot be used as a target, but it does not explicitly mention alternatives or when not to use this tool.

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