Claude web fetch

by AnthropicWeb fetch

Web fetch is Anthropic's server tool that lets Claude fetch and read full web pages and PDFs while it answers. It only fetches URLs that already appear in the conversation, never ones Claude writes itself, respects robots.txt, and can cite the passages it uses. Pages that only render with JavaScript are out of reach. On Opper, Claude gets it on the Messages endpoint, passed through as Anthropic defines it. It runs on Anthropic's own route; Claude served from Bedrock or Vertex doesn't have it.

UseClaude web fetchwithin

Add Claude web fetch on Opper

Set up with agents

Paste this into your coding agent (Claude Code, Cursor, Codex, and more) and it will set up and build with Opper for you.

Get your API key

Key info

Tool

web_fetch

Endpoint

Messages

Routes

Anthropic

In your code

1curl https://api.opper.ai/v3/compat/v1/messages \
2  -H "Authorization: Bearer $OPPER_API_KEY" \
3  -H "Content-Type: application/json" \
4  -d '{"model": "anthropic/claude-haiku-5-5", "max_tokens": 1024,
5       "messages": [{"role": "user", "content": "Summarise https://opper.ai/pricing"}],
6       "tools": [{"type": "web_fetch_20250910", "name": "web_fetch", "max_uses": 3}]}'

Use Claude web fetch with these models

Step-by-step setup for Claude web fetch on each of these models through Opper.

Claude Haiku 5.5 Claude Sonnet 5.5 Claude Opus 5.5 Claude Fable 5.1 Claude Opus 5 Claude Sonnet 5 Claude Fable 5 Claude Opus 4.8 See all 700+ models

More tools on Opper

Jina Reader

Turn any URL into clean markdown a model can read. Opper's web fetch, running in the EU.

Read/v3/tools/web/fetch

Gemini URL context

Gemini reads the URLs in your prompt itself, on generateContent.

ReadurlContext

Jina search

Opper's default search engine for models without their own. Search processing stays in the EU.

Search"engine": "jina"