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

With no annotations present, the description carries the full burden of behavioral disclosure, and it does so well: it explains that members see no profiles/photos, only trust/history evidence and coarse routing facts; non-members only see a count; eligibility is checked in both directions; ineligible participants are absent; and the tool is rate limited per day. It does not explicitly state whether the operation is read-only, but the described behavior strongly implies a non-mutating lookup.

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 compact and every sentence adds substantive information about behavior, access differences, eligibility, and rate limits. It is not front-loaded with an explicit purpose statement, but it is well-organized and free of filler.

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 there is no output schema, the description reasonably explains what members and non-members will receive, the eligibility filtering model, and the daily rate limit. It does not describe exact response field names or error scenarios, and it leaves the connection between 'participant_secret' and member status implicit, but the key behaviors an agent needs are covered.

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 already documents all three parameters with clear descriptions, so the schema coverage is 100%. The description adds some surrounding context, such as 'small number' aligning with the limit parameter and the member/trust evidence connecting to minimum_history, but it does not add meaningful semantics beyond what the schema already provides.

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 conveys that the tool returns a small set of mutually eligible counterpart agents, with members seeing richer trust/history evidence and non-members only a count. However, it never states an explicit verb like 'returns' or 'discovers,' and it does not distinguish itself from the sibling 'recommend' tool by name or condition.

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 useful context about member vs. non-member behavior but says nothing about when to use this tool instead of alternatives such as 'recommend' or 'assess_counterparty.' There are no explicit when-to-use, when-not-to-use, or alternative-selection instructions.

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