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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safe read-only nature is covered. The description adds valuable behavioral context: login required, max 60 hard limit, only already-joined users are included (with rationale that unjoined profiles are empty), and what the inPool flag means. This goes beyond annotations and explains data quality semantics.

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 organized into three labeled sections (login/limit, combo chain, definitions). Each sentence serves a purpose, and the core behavior is front-loaded. It is not overly verbose, and the structure makes it easy for an agent to parse quickly. Slight redundancy exists with the schema, but it is tolerable.

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 a single optional parameter and no output schema, the description covers the key operational facts: ordering, limit, inclusion criteria, the inPool flag, and the downstream chain. It does not enumerate the returned fields beyond inPool, but for a list-style read tool with annotations already covering safety, this is sufficient for correct invocation and basic result interpretation.

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 100%: the single `limit` parameter is fully documented with default, min, max, and a service-layer hard cap. The description only restates '最多 60' without adding new parameter semantics. Since the schema already carries full parameter meaning, the baseline score of 3 is 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 clearly states the tool lists '刚入驻的人' (people who just joined) in reverse chronological order of join time, capped at 60. It explicitly narrows the scope to '已入驻' (already onboarded) individuals, distinguishing it from listing existing leads or searching all people. This is a specific verb+resource with clear output semantics, and the tool name and title reinforce the same intent.

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 a concrete usage chain (list_broker_fresh_joiners → pick complementary leads → collect_broker_leads → scan_broker_matches) and positions it as the entry point for daily 'worth collecting' checks. It also warns not to re-collect when inPool=true. While it does not explicitly contrast with alternatives like list_broker_leads, the chain and context make the intended use clear.

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