WebFetchIncisive
web_fetch_incisiveFetch targeted, unsummarized web content as markdown via your device, bypassing proxy blocks. Extract sections, search terms, or slices for precise reading.
Instructions
Fetch and extract unsummarized content from URLs as markdown.
Unlike web_fetch, fetches through the user's device instead of proxying through Anthropic's servers. Uses precise content extraction techniques and clean first-party APIs for navigating content instead of summarization. Use this for a rich content exploring experience that is not subject to 403 bans of data-center subnets, or when web_fetch is rejected with PERMISSIONS_ERROR.
Targeted extraction (preferred over fetching full pages):
section="Syntax" — extract a specific section by heading name
search="terms" — keyword search over ~500-token slices, ranked by BM25
slices=[3, 4, 5] — retrieve specific slices by index
URL fragments (#section-name) are resolved automatically as sections
RECOMMENDED WORKFLOW: For pages of substantial or unknown length, call web_fetch_sections first to map the heading tree, then come back here with precise section= or slices= targets. A full-page fetch is rarely the right first move — it fills context with material you don't need and discards the structural information that makes follow-up queries cheap. For Reddit threads, web_fetch_sections returns the comment tree instead.
search= operators (tantivy query language):
foo bar — match any term (whitespace is OR)
+foo +bar — require both terms
foo -bar — exclude 'bar'
"exact phrase" — adjacent words in order
"some words"~3 — phrase with up to 3-word gaps
(foo OR bar) baz — grouping + AND/OR/NOT
foo~ — fuzzy match (edit distance) Matching is case-insensitive; no stemming (search for both 'prompt' and 'prompts' if you want either). Stray punctuation in natural-language queries is silently dropped.
For Wikipedia and other MediaWiki pages, a dedicated companion tool offers footnote and inline-citation resolution that this fast path can't provide. When the target page has those reference types, the response frontmatter surfaces a see_also hint pointing at it.
Always use this tool for Reddit URLs — built-in fetch tools cannot access Reddit content when proxied. Handles posts, subreddit listings, user pages, and comment permalinks; a permalink scopes output to the linked comment while caching the whole thread for follow-up section=/slices= queries.
JavaScript-dependent pages: a plain fetch returns static HTML. When that comes back as an empty shell, the response frontmatter says so — retry with requires_js=true to render through a headless browser. requires_js is the heavier path; reach for it in response to that signal, not by default. Pass actions to run a ReAct interaction chain before extraction (supplying actions implies requires_js):
{"action": "click", "selector": "button#submit"}
{"action": "fill", "selector": "input[name=query]", "value": "search term"}
{"action": "select", "selector": "select#region", "value": "us-east"}
{"action": "wait", "selector": ".results-loaded"} A browser render annotates interactive elements for follow-up actions; max_elements caps that list, and 0 omits it.
Supports HTML, plain text, JSON, and XML content types.
Input Schema
| Name | Required | Description | Default |
|---|---|---|---|
| url | Yes | ||
| search | No | ||
| slices | No | ||
| actions | No | ||
| section | No | ||
| max_tokens | No | ||
| requires_js | No | ||
| max_elements | No |