list_languages

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

With no annotations, the description carries the full burden of behavioral disclosure. It states the action but does not mention return format, potential errors, or any dependencies (e.g., whether an indexer must be loaded). For a trivial read-only query, this is acceptable but lacks detail about the output structure.

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?

A single, clear sentence with no filler. The description is front-loaded with the action and resource, making it instantly understandable.

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 (no parameters, no annotations, no output schema), the description is nearly complete. It states what it returns but does not specify the format (e.g., array of strings) or any prerequisites. Since the tool is self-explanatory, this is adequate, though slightly more detail could be added.

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, and the schema coverage is 100% (vacuously). Per the rubric, a 0-parameter tool gets a baseline of 4. The description does not need to add parameter details since none exist.

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 function: returning the supported languages of the indexer. It uses a specific verb ('Return') and a clear resource ('languages this indexer supports'), making it distinct from sibling tools like stats, search_symbols, or find_imports. No ambiguity or tautology.

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 implicitly indicates this is a simple query to retrieve language support. There are no closely related alternatives among siblings, so explicit when-not guidance is unnecessary. However, it does not explicitly state when an agent should call it, but the context is clear given the tool's purpose.

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