Fetch and read the main content of a specified web page, removing ads, navigation, footers, and clutter to return clean Markdown, plain text, or a summary.
抓取并深度阅读指定网页的正文。自动过滤广告、导航、页脚与杂乱代码，支持输出纯正文或规范的 Markdown 格式。
| Name | Required | Description | Default |
|---|---|---|---|
| url | Yes | 目标网页的完整 URL (必须以 http:// 或 https:// 开头) | |
| extract_mode | No | 正文提取格式: 'markdown' (结构化文档，默认), 'text' (纯文本), 'summary' (核心要点摘要) | markdown |
Changes observed during successful MCP inspections.
v1.0.6Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description carries the full burden. It usefully discloses that ads, navigation, footers and messy code are stripped and that body content is extracted, but says nothing about auth needs, rate limits, JS rendering, or failure behavior for unreachable pages.
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?
Two short sentences with zero waste; the primary action and its filtering behavior are front-loaded, followed by the output-format note. Nothing redundant.
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 tool with no output schema, the description covers purpose, content-cleaning behavior, and output formats adequately. It is slightly thin on guidance about when a search-then-fetch is warranted, but nothing essential to calling it correctly is missing.
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%, so both url and extract_mode are already documented in the schema, giving a baseline of 3. The description mentions plain-text and Markdown outputs but omits the 'summary' extract mode, adding no meaningful detail beyond the enum.
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 states a specific verb (抓取/深度阅读) and resource (指定网页的正文), making the core operation unmistakable. It does not explicitly contrast itself with the sibling devin_web_search, so an agent must infer the fetch-vs-search distinction, 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?
Usage is only implied: the tool takes a URL, so the agent must already have a target page. There is no explicit statement of when to prefer this over devin_web_search or what precondition (a known URL) selects it.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.