PR #49954: feat: add Anthropic native web search provider (web_search_20260209)

• Repository: openclaw/openclaw
• Author: metasal1
• State: open | merged: False
• Link: https://github.com/openclaw/openclaw/pull/49954

Description (problem / solution / changelog)

Summary

Adds Anthropic's native web search as a new web search provider for OpenClaw, enabling users to leverage Claude's built-in web_search_20250305 / web_search_20260209 server-side tool.

Closes #49949

Architecture Note

All existing web search providers (Brave, Gemini, Perplexity, etc.) are client-side — OpenClaw intercepts web_search tool calls and routes them to external search APIs. Anthropic's web search is fundamentally different: it's a server-side tool that gets passed in the tools array of the Messages API, and Claude executes searches autonomously.

This PR bridges the gap pragmatically: the provider makes a direct call to the Anthropic Messages API with the web_search tool enabled, extracts the search results and citations from the response, and returns them in OpenClaw's standard format. This works within the existing architecture while leveraging Anthropic's native search.

Future optimization: A more native integration could detect when the active model is Anthropic and inject web_search_20260209 directly into the tools array, bypassing client-side interception entirely. This would be more token-efficient and support streaming search results.

Changes

• extensions/anthropic/anthropic-web-search-provider.ts — New provider implementation
• extensions/anthropic/index.ts — Register the web search provider
• extensions/anthropic/openclaw.plugin.json — Declare web search provider + config schema
• src/plugins/bundled-web-search.ts — Add anthropic to bundled provider list

Configuration

{
  "tools": {
    "web": {
      "search": {
        "provider": "anthropic",
        "anthropic": {
          "toolVersion": "web_search_20260209",
          "maxUses": 5,
          "allowedDomains": [],
          "blockedDomains": [],
          "userLocation": {
            "type": "approximate",
            "city": "San Francisco",
            "region": "California",
            "country": "US",
            "timezone": "America/Los_Angeles"
          }
        }
      }
    }
  }
}

API key reuses existing Anthropic auth (ANTHROPIC_API_KEY env var or configured profile).

Changed files

• extensions/anthropic/anthropic-web-search-provider.ts (added, +401/-0)
• extensions/anthropic/index.ts (modified, +2/-0)
• extensions/anthropic/openclaw.plugin.json (modified, +14/-1)
• src/plugins/bundled-web-search.ts (modified, +1/-0)

PR #50692: feat: add Anthropic native web search provider (#49949)

• Repository: openclaw/openclaw
• Author: henry-the-frog
• State: open | merged: False
• Link: https://github.com/openclaw/openclaw/pull/50692

Description (problem / solution / changelog)

Summary

Adds "anthropic" as a new web search provider option, enabling Anthropic's server-side web_search_20260209 tool to be injected directly into the Messages API request. Claude handles search execution server-side with built-in citations, domain filtering, and prompt caching.

Closes #49949

What changed

New files

• extensions/anthropic/src/anthropic-web-search-provider.ts — Provider plugin implementing the WebSearchProviderPlugin interface. Resolves config (tool version, allowed/blocked domains, max uses, user location) and builds the raw Anthropic server tool definition.
• extensions/anthropic/src/anthropic-native-search-wrapper.ts — Stream wrapper that intercepts the onPayload callback to inject the server tool into the tools array for anthropic-messages API calls. Skips injection if a web_search server tool is already present.

Modified files

• extensions/anthropic/index.ts — Registers the new web search provider.
• src/plugins/bundled-web-search.ts — Adds "anthropic" to the bundled web search plugin ID list.

Tests (18 passing)

• anthropic-web-search.test.ts (15 tests) — Config resolution, tool version validation, server tool building (domains, max_uses, user_location, edge cases).
• anthropic-native-search-wrapper.test.ts (3 tests) — Injection into anthropic payloads, dedup when already present, passthrough for non-anthropic APIs.

Configuration

{
  tools: {
    web: {
      search: {
        provider: "anthropic",
        anthropic: {
          toolVersion: "web_search_20260209",  // or "web_search_20250305"
          allowedDomains: ["example.com"],
          blockedDomains: ["untrusted.com"],
          maxUses: 5,
          userLocation: {
            type: "approximate",
            city: "Denver",
            region: "Colorado",
            country: "US",
            timezone: "America/Denver"
          }
        }
      }
    }
  }
}

How it works

Unlike other providers that intercept web_search tool calls and route them to external APIs, this provider uses Anthropic's server tool mechanism. The stream wrapper patches the API payload to include the web_search_20260209 tool, and Claude executes searches server-side. Results come back as server_tool_use / web_search_tool_result content blocks with encrypted content and built-in citations.

No separate API key needed — uses the existing Anthropic API key.

Changed files

• extensions/anthropic/index.ts (modified, +8/-0)
• extensions/anthropic/src/anthropic-native-search-wrapper.test.ts (added, +54/-0)
• extensions/anthropic/src/anthropic-native-search-wrapper.ts (added, +58/-0)
• extensions/anthropic/src/anthropic-web-search-provider.ts (added, +175/-0)
• extensions/anthropic/src/anthropic-web-search.test.ts (added, +122/-0)
• openclaw-2026-03-18.log (added, +130/-0)
• openclaw-2026-03-25.log (added, +3/-0)
• src/bundled-web-search-registry.ts (modified, +7/-0)