Fetch Web Md

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

With no annotations, the description carries the burden of behavioral disclosure. It does disclose the return shape (page title + Markdown body), the preservation of structure, and the max_chars truncation. It does not mention error behavior, non-HTML responses, or other edge cases, but for a read-only fetch tool this is a reasonable but not thorough disclosure.

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 front-loaded with the core action, uses a compact parameter/return structure, and contains no filler. Every sentence contributes to understanding what the tool does and what it returns.

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 simple two-parameter fetch-and-convert tool, the description covers input, output, truncation, and recommended use case. The output schema further reduces the need to explain return values. It is slightly incomplete regarding explicit sibling routing and failure behavior, but overall sufficient.

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 schema documents max_chars well, but url has no schema-level description. The tool description adds a concrete URL example for url and restates the meaning of max_chars, so it partially compensates for the 50% schema coverage. It does not add much depth beyond the example.

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 action: '抓取一个网页并转换为 Markdown' and specifies what Markdown elements are preserved. It doesn't explicitly distinguish from the sibling fetch_web, but the Markdown-vs-plain-text framing makes the differentiation largely inferable.

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 gives a clear intended use case: '比纯文本更适合喂给 LLM / 文档化场景'. However, it does not explicitly say when to prefer this over siblings like fetch_web or fetch_urls, nor does it state when not to use it.

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