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Tool description

WebFetch, as sent

CLI Claude Code, interactive mode, v2.1.269. 17 model strings share this prompt, byte for byte.

Lines211,608 characters
Moved+0−0 against v2.1.268
Reach17model strings receive this description
Copies2distinct descriptions under this name
Parameters22 of them required Tools in captureall of themevery description on this arm
2 genuinely different descriptions of this tool Plain text · sha256 d3dc99188f10

The description, rendered

This renders the markdown inside the description, so it isn’t quite the description itself.

The raw view and the plain text are the bytes as they were sent.

IMPORTANT: WebFetch WILL FAIL for authenticated or private URLs. Before using this tool, check if the URL points to an authenticated service (e.g. Google Docs, Confluence, Jira, GitHub). If so, look for a specialized MCP tool that provides authenticated access.

  • Fetches content from a specified URL and processes it using an AI model
  • Takes a URL and a prompt as input
  • Fetches the URL content, converts HTML to markdown
  • Processes the content with the prompt using a small, fast model
  • Returns the model's response about the content
  • Use this tool when you need to retrieve and analyze web content

Usage notes:

  • IMPORTANT: If an MCP-provided web fetch tool is available, prefer using that tool instead of this one, as it may have fewer restrictions.
  • The URL must be a fully-formed valid URL
  • HTTP URLs will be automatically upgraded to HTTPS
  • localhost and other hostnames without a dot are not supported; for a local server, use curl via Bash
  • The prompt should describe what information you want to extract from the page
  • This tool is read-only and does not modify any files
  • Results may be summarized if the content is very large
  • Includes a self-cleaning cache (entries expire after 15 minutes) for faster responses when repeatedly accessing the same URL
  • When a URL redirects to a different host, the tool will inform you and provide the redirect URL in a special format. You should then make a new WebFetch request with the redirect URL to fetch the content.
  • For GitHub URLs, prefer using the gh CLI via Bash instead (e.g., gh pr view, gh issue view, gh api).

What it accepts

2 parameters The JSON parameter schema sent beside this description, 380 characters of it. Name, type, then whether the client marked it required.
prompt string required The prompt to run on the fetched content
url string required The URL to fetch content from

sha256 79f70c017c3b · the schema as the client sent it:

{ "$schema": "https://json-schema.org/draft/2020-12/schema", "additionalProperties": false, "properties": { "prompt": { "description": "The prompt to run on the fetched content", "type": "string" }, "url": { "description": "The URL to fetch content from", "format": "uri", "type": "string" } }, "required": [ "url", "prompt" ], "type": "object" }