list_session_senders

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

Annotations already declare the operation read-only and non-destructive. The description adds useful behavioral context beyond annotations: results are limited to scanned messages and aggregated by sender, and the output is not a full roster. This helps set accurate expectations.

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 sentence that front-loads the action and target, then adds purpose and a key limitation. Every part earns its place with no redundant wording.

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 read-only list operation, the description adequately conveys what is returned (speakers and counts) and the important scope restriction (scanned messages only). Pagination and exact return shape are not detailed, but the absence of an output schema and the simplicity of the tool make this a minor gap.

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?

Schema description coverage is 0%, and the description does not explain the meaning or usage of session_id, limit, or offset. The pagination parameters are left entirely to inference from their names, and the description does not compensate for the lack of schema documentation.

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?

Description states a specific verb and resource: it lists speakers and their counts within a session's scanned messages. It also distinguishes itself by clarifying it is not a complete group member list, which separates it from sibling tools like list_contacts.

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 clear intended use ('供按人精确筛选') and an explicit exclusion ('不是完整群成员名单'). However, it does not name a specific alternative tool, so the guidance is strong but not fully explicit about when not to use it in favor of a sibling.

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