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Web Fetch

The web_fetch tool does a plain HTTP GET and extracts readable content (HTML to markdown or text). It does not execute JavaScript. For JS-heavy sites or login-protected pages, use the Web Browser instead.

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Quick start

web_fetch is enabled by default — no configuration needed. The agent can call it immediately: 
await web_fetch({ url: "https://example.com/article" });

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Tool parameters

ParameterTypeDescription
urlstringURL to fetch (required, http/https only)
extractModestring"markdown" (default) or "text"
maxCharsnumberTruncate output to this many chars

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How it works

1

Fetch

Sends an HTTP GET with a Chrome-like User-Agent and Accept-Language header. Blocks private/internal hostnames and re-checks redirects.
2

Extract

Runs Readability (main-content extraction) on the HTML response.
3

Fallback (optional)

If Readability fails and Firecrawl is configured, retries through the Firecrawl API with bot-circumvention mode.
4

Cache

Results are cached for 15 minutes (configurable) to reduce repeated fetches of the same URL.

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Config

{
  tools: {
    web: {
      fetch: {
        enabled: true, // default: true
        maxChars: 50000, // max output chars
        maxCharsCap: 50000, // hard cap for maxChars param
        maxResponseBytes: 2000000, // max download size before truncation
        timeoutSeconds: 30,
        cacheTtlMinutes: 15,
        maxRedirects: 3,
        readability: true, // use Readability extraction
        userAgent: "Mozilla/5.0 ...", // override User-Agent
      },
    },
  },
}

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Firecrawl fallback

If Readability extraction fails, web_fetch can fall back to Firecrawl for bot-circumvention and better extraction: 
{
  tools: {
    web: {
      fetch: {
        firecrawl: {
          enabled: true,
          apiKey: "fc-...", // optional if FIRECRAWL_API_KEY is set
          baseUrl: "https://api.firecrawl.dev",
          onlyMainContent: true,
          maxAgeMs: 86400000, // cache duration (1 day)
          timeoutSeconds: 60,
        },
      },
    },
  },
}
tools.web.fetch.firecrawl.apiKey supports SecretRef objects.
If Firecrawl is enabled and its SecretRef is unresolved with no FIRECRAWL_API_KEY env fallback, gateway startup fails fast.

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Limits and safety

  • maxChars is clamped to tools.web.fetch.maxCharsCap
  • Response body is capped at maxResponseBytes before parsing; oversized responses are truncated with a warning
  • Private/internal hostnames are blocked
  • Redirects are checked and limited by maxRedirects
  • web_fetch is best-effort — some sites need the Web Browser

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Tool profiles

If you use tool profiles or allowlists, add web_fetch or group:web: 
{
  tools: {
    allow: ["web_fetch"],
    // or: allow: ["group:web"]  (includes both web_fetch and web_search)
  },
}
  • Web Search — search the web with multiple providers
  • Web Browser — full browser automation for JS-heavy sites
  • Firecrawl — Firecrawl search and scrape tools