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

No annotations are provided, so the description must disclose behavioral traits. It only states that the tool lists 'sitting' members, which implies a filter for currently-serving members. It does not mention pagination, default limits, response format, or whether it is read-only. This is a minimal disclosure for a list tool with no annotations.

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 concise sentence that front-loads the core purpose. It contains no fluff or redundant information, earning a maximum score for efficiency.

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?

The tool has 4 optional parameters and no output schema. The description is extremely brief and does not explain return values or edge cases, but the simple listing purpose and well-documented schema make it minimally acceptable. It lacks helpful context like whether filters combine, but this is a straightforward list tool.

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 input schema has 100% description coverage for all 4 parameters, so the schema already explains limit, state, chamber, and currentMember. The description adds no parameter-specific meaning. Per the rubric, baseline is 3 when schema coverage is high, and there is no additional insight from the description.

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 action (list) and resource (sitting US Congress members). It is specific and unambiguous, though it doesn't explicitly distinguish from sibling tools like get_congress_member, which likely retrieves a single member. The inclusion of 'sitting' adds specificity beyond 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?

The description gives no guidance on when to use this tool versus alternatives such as get_congress_member or query_gov. There is no mention of use cases, prerequisites, or exclusions. The appropriate usage is only implied by the tool's name and basic verb-noun structure.

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