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

No annotations are provided, so the description carries the full burden. It discloses a useful output trait — only relevant lines with line numbers are returned, to save tokens — but says nothing about network access for URLs, latency, rate limits, failure behavior, or how 原文/网址 interact. Some behavioral value, but significant gaps remain.

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?

A single front-loaded sentence that names the operation, inputs, output shape, and benefit with no filler. It is well-structured; the only knock is that its brevity comes at the cost of the missing parameter and routing detail noted elsewhere.

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?

With 5 parameters, 0 required, no annotations, no output schema, and 40% schema coverage, the description is thin for the tool's complexity. It covers the core operation but leaves the url-vs-text selection logic and the context/max_lines behavior entirely to inference.

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 only 40% (url and text, both described merely as '二选一'/choose one). The description clarifies url/text and the keyword (query), but context and max_lines are documented in neither the schema nor the description, leaving two parameters with no semantics at all.

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: 长文本检索 (long-text retrieval) that takes raw text or a URL plus a keyword and returns matching lines with line numbers. An agent can tell this is a keyword-search-over-long-text tool. It does not differentiate itself from the nearest sibling web_read, which also handles URL content, so it falls 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?

The description indicates the input mode (pass original text or a URL plus a keyword), which is a form of usage guidance. It never says when to choose this over web_read or when it is inappropriate (e.g., for short text or non-text content), so guidance remains implied rather than explicit.

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