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

Goes beyond the annotations by disclosing that phone-number queries return empty for privacy, that claimed profiles are ranked first, that login can supplement cloud users, and that direct chat is not possible. This is rich behavioral context; only the reason 'readOnlyHint=false' is a write is left slightly implicit.

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?

Front-loaded with the core purpose, then constraints, then the combination chain. It is dense with jargon and bracketed tags 【组合链】 but each clause carries distinct information, so little waste.

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 2-param, no-output-schema tool this covers purpose, scoring/ranking behavior, privacy behavior, auth effect, and routing to siblings. The gap is that the readOnlyHint=false implication (state modification when logged in) is only hinted at, not spelled out.

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 coverage is 100% – q and limit are both documented in-schema. The description adds the useful framing that q is about what the other party can offer (canOffer) and supports natural language, but no syntax or format details beyond the schema, so the baseline 3 applies.

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?

States a specific verb+resource (search real people by canOffer semantics + keyword) and the scope (real humans, claimed profiles prioritized). It also names the sibling tools it is not (search_products / search_needs), so an agent can route correctly without opening schemas.

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?

Explicitly routes alternatives: products and needs go to search_products / search_needs, and the intended follow-on chain is given as get_creator → start_conversation/contact_need. It also states the constraints 'cannot open chat, only send_cooperation_request is manually relayed.'

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