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

Beyond readOnlyHint=true, it discloses that the call is zero-LLM, that source=inferred is expected/normal, that upstream and downstream are excluded, and that an unplaced count is returned. These are non-obvious behavioral facts not present in the annotations. It stops short of describing output shape in detail, but no output schema exists to lean on.

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?

It is short and front-loads the key fact (login, zero-LLM read), but the semicolon-chained telegraphic phrasing and abbreviations like '空先补资料' force the reader to decode intent. No sentence is wasted, yet the structure trades clarity for density.

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 zero-param read-only tool with no output schema, the description covers what is returned, what is excluded, how to interpret source=inferred, and which sibling to fall back to. An agent can call it and act on the result without further information; only the exact response field names remain unspecified.

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 tool takes zero parameters, so the schema carries no semantics to add to; the description correctly spends no space on parameters and instead explains the results. Baseline for 0 params is 4.

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 names the specific resource (my own and published product anchors) and enumerates what is returned: anchor, chain-position original text, and unplaced count. It also states a clear boundary ('不含上下游'), which separates it from get_chain_anchor. The verb is only implicit through the tool name, and the jargon '归位现状' is dense, keeping it short of a 5.

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?

Explicit routing is given for every adjacent case: empty result → 先补资料, placed=false → set_my_chain_position, and upstream/downstream needs → get_chain_anchor with the caveat that it costs LLM. It even names an anti-pattern ('不要为读标题调用它'), which is exactly what an agent needs to choose correctly.

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