etf_list_sector

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

There are no annotations, so the description bears the full weight of behavioral disclosure. It does state that the tool returns 'unique' sector values, which is a meaningful behavioral detail (no duplicates). However, it omits any mention of output format, ordering, error handling, or limitations. For a trivial parameterless tool, this is acceptable but not elaborate; the description adds only a single behavioral trait beyond the name.

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 a single, tightly scoped sentence. It directly states the action and the result without superfluous words. It is exceptionally concise and front-loaded, with no wasted content.

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 tool with no output schema, the description provides the essential information: what it returns (unique sector values for ETFs). It does not specify the exact return structure (e.g., array of strings), but given the simplicity and the naming pattern, an agent can reasonably infer the output. The description is sufficient for correct invocation, though a note on output format would push it to a 5.

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 per rubric is 4. The schema is empty, and the description adds nothing about parameters (since there are none). No further semantic clarification is needed, making the baseline score 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 uses a specific verb ('Get') and a precise resource ('unique sector values for ETFs'). This clearly distinguishes it from sibling tools like etf_list_industry or etf_list_country, which target different classification dimensions. The purpose is unambiguous and directly aligned with the tool name.

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?

No explicit guidance is given on when to use this tool versus alternatives. However, the naming convention and description make the intended use obvious: to retrieve the set of sector categories available for ETFs. This is implied usage rather than explicit, so a score of 3 is appropriate.

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