Add web fetch tool support for Anthropic

homeassistant/components/anthropic/config_flow.py

@@ -28,8 +28,7 @@
     CONF_NAME,
 )
 from homeassistant.core import HomeAssistant, callback
-from homeassistant.helpers import llm
-import homeassistant.helpers.config_validation as cv
+from homeassistant.helpers import config_validation as cv, llm
 from homeassistant.helpers.httpx_client import get_async_client
 from homeassistant.helpers.selector import (
     NumberSelector,
@@ -52,6 +51,8 @@
     CONF_THINKING_BUDGET,
     CONF_THINKING_EFFORT,
     CONF_TOOL_SEARCH,
+    CONF_WEB_FETCH,
+    CONF_WEB_FETCH_MAX_USES,
     CONF_WEB_SEARCH,
     CONF_WEB_SEARCH_CITY,
     CONF_WEB_SEARCH_COUNTRY,
@@ -459,6 +460,14 @@ async def async_step_model(
                     CONF_WEB_SEARCH_USER_LOCATION,
                     default=DEFAULT[CONF_WEB_SEARCH_USER_LOCATION],
                 ): bool,
+                vol.Optional(
+                    CONF_WEB_FETCH,
+                    default=DEFAULT[CONF_WEB_FETCH],
+                ): bool,
+                vol.Optional(
+                    CONF_WEB_FETCH_MAX_USES,
+                    default=DEFAULT[CONF_WEB_FETCH_MAX_USES],
+                ): cv.positive_int,
             }
         )
 

homeassistant/components/anthropic/const.py

@@ -18,6 +18,8 @@
 CONF_THINKING_BUDGET = "thinking_budget"
 CONF_THINKING_EFFORT = "thinking_effort"
 CONF_TOOL_SEARCH = "tool_search"
+CONF_WEB_FETCH = "web_fetch"
+CONF_WEB_FETCH_MAX_USES = "web_fetch_max_uses"
 CONF_WEB_SEARCH = "web_search"
 CONF_WEB_SEARCH_USER_LOCATION = "user_location"
 CONF_WEB_SEARCH_MAX_USES = "web_search_max_uses"
@@ -45,6 +47,8 @@ class PromptCaching(StrEnum):
     CONF_THINKING_BUDGET: MIN_THINKING_BUDGET,
     CONF_THINKING_EFFORT: "low",
     CONF_TOOL_SEARCH: False,
+    CONF_WEB_FETCH: False,
+    CONF_WEB_FETCH_MAX_USES: 5,
     CONF_WEB_SEARCH: False,
     CONF_WEB_SEARCH_USER_LOCATION: False,
     CONF_WEB_SEARCH_MAX_USES: 5,

homeassistant/components/anthropic/entity.py

@@ -16,8 +16,6 @@
     Base64PDFSourceParam,
     BashCodeExecutionToolResultBlock,
     CitationsDelta,
-    CitationsWebSearchResultLocation,
-    CitationWebSearchResultLocationParam,
     CodeExecutionTool20250825Param,
     CodeExecutionToolResultBlock,
     CodeExecutionToolResultBlockParamContentParam,
@@ -65,6 +63,9 @@
     ToolUseBlock,
     ToolUseBlockParam,
     Usage,
+    WebFetchTool20250910Param,
+    WebFetchTool20260209Param,
+    WebFetchToolResultBlock,
     WebSearchTool20250305Param,
     WebSearchTool20260209Param,
     WebSearchToolResultBlock,
@@ -80,6 +81,9 @@
 from anthropic.types.tool_search_tool_result_block_param import (
     Content as ToolSearchToolResultBlockParamContentParam,
 )
+from anthropic.types.web_fetch_tool_result_block_param import (
+    Content as WebFetchToolResultBlockParamContentParam,
+)
 import voluptuous as vol
 from voluptuous_openapi import convert
 
@@ -91,7 +95,7 @@
 from homeassistant.helpers.json import json_dumps
 from homeassistant.helpers.update_coordinator import CoordinatorEntity
 from homeassistant.util import slugify
-from homeassistant.util.json import JsonObjectType
+from homeassistant.util.json import JsonArrayType, JsonObjectType
 
 from .const import (
     CONF_CHAT_MODEL,
@@ -101,6 +105,8 @@
     CONF_THINKING_BUDGET,
     CONF_THINKING_EFFORT,
     CONF_TOOL_SEARCH,
+    CONF_WEB_FETCH,
+    CONF_WEB_FETCH_MAX_USES,
     CONF_WEB_SEARCH,
     CONF_WEB_SEARCH_CITY,
     CONF_WEB_SEARCH_COUNTRY,
@@ -191,17 +197,9 @@ def add_citation(self, citation: TextCitation) -> None:
         """Add a citation to the current detail."""
         if not self.citation_details:
             self.citation_details.append(CitationDetails())
-        citation_param: TextCitationParam | None = None
-        if isinstance(citation, CitationsWebSearchResultLocation):
-            citation_param = CitationWebSearchResultLocationParam(
-                type="web_search_result_location",
-                title=citation.title,
-                url=citation.url,
-                cited_text=citation.cited_text,
-                encrypted_index=citation.encrypted_index,
-            )
-        if citation_param:
-            self.citation_details[-1].citations.append(citation_param)
+        self.citation_details[-1].citations.append(
+            cast(TextCitationParam, citation.to_dict())
+        )
 
     def delete_empty(self) -> None:
         """Delete empty citation details."""
@@ -272,6 +270,15 @@ def _convert_content(  # noqa: C901
                         content.tool_result,
                     ),
                 }
+            elif content.tool_name == "web_fetch":
+                tool_result_block = {
+                    "type": "web_fetch_tool_result",
+                    "tool_use_id": content.tool_call_id,
+                    "content": cast(
+                        WebFetchToolResultBlockParamContentParam,
+                        content.tool_result,
+                    ),
+                }
             else:
                 tool_result_block = {
                     "type": "tool_result",
@@ -398,6 +405,7 @@ def _convert_content(  # noqa: C901
                             id=tool_call.id,
                             name=cast(
                                 Literal[
+                                    "web_fetch",
                                     "web_search",
                                     "code_execution",
                                     "bash_code_execution",
@@ -411,6 +419,7 @@ def _convert_content(  # noqa: C901
                         if tool_call.external
                         and tool_call.tool_name
                         in [
+                            "web_fetch",
                             "web_search",
                             "code_execution",
                             "bash_code_execution",
@@ -573,6 +582,7 @@ async def _transform_stream(  # noqa: C901 - This is complex, but better to have
             elif isinstance(
                 response.content_block,
                 (
+                    WebFetchToolResultBlock,
                     WebSearchToolResultBlock,
                     CodeExecutionToolResultBlock,
                     BashCodeExecutionToolResultBlock,
@@ -593,7 +603,7 @@ async def _transform_stream(  # noqa: C901 - This is complex, but better to have
                     ),
                     "tool_result": {
                         "content": cast(
-                            JsonObjectType, response.content_block.to_dict()["content"]
+                            JsonArrayType, response.content_block.to_dict()["content"]
                         )
                     }
                     if isinstance(response.content_block.content, list)
@@ -718,6 +728,7 @@ async def _get_model_args(  # noqa: C901
             "GetLiveContext",
             "code_execution",
             "web_search",
+            "web_fetch",
         ]
 
         system = chat_log.content[0]
@@ -791,11 +802,14 @@ async def _get_model_args(  # noqa: C901
             ]
 
         if options[CONF_CODE_EXECUTION]:
-            # The `web_search_20260209` tool automatically enables `code_execution_20260120` tool
+            # The `web_search_20260209` and `web_fetch_20260209` tools
+            # automatically enable `code_execution_20260120` tool
             if (
                 not self.model_info.capabilities
                 or not self.model_info.capabilities.code_execution.supported
-                or not options[CONF_WEB_SEARCH]
+                or (
+                    not options[CONF_WEB_SEARCH] and not options[CONF_WEB_FETCH]
+                )
             ):
                 tools.append(
                     CodeExecutionTool20250825Param(
@@ -833,6 +847,28 @@ async def _get_model_args(  # noqa: C901
                 }
             tools.append(web_search)
 
+        if options[CONF_WEB_FETCH]:
+            if (
+                not self.model_info.capabilities
+                or not self.model_info.capabilities.code_execution.supported
+                or not options[CONF_CODE_EXECUTION]
+            ):
+                tools.append(
+                    WebFetchTool20250910Param(
+                        name="web_fetch",
+                        type="web_fetch_20250910",
+                        max_uses=options[CONF_WEB_FETCH_MAX_USES],
+                    )
+                )
+            else:
+                tools.append(
+                    WebFetchTool20260209Param(
+                        name="web_fetch",
+                        type="web_fetch_20260209",
+                        max_uses=options[CONF_WEB_FETCH_MAX_USES],
+                    )
+                )
+
         # Handle attachments by adding them to the last user message
         last_content = chat_log.content[-1]
         if last_content.role == "user" and last_content.attachments:

homeassistant/components/anthropic/strings.json

@@ -80,6 +80,8 @@
             "thinking_effort": "[%key:component::anthropic::config_subentries::conversation::step::model::data::thinking_effort%]",
             "tool_search": "[%key:component::anthropic::config_subentries::conversation::step::model::data::tool_search%]",
             "user_location": "[%key:component::anthropic::config_subentries::conversation::step::model::data::user_location%]",
+            "web_fetch": "[%key:component::anthropic::config_subentries::conversation::step::model::data::web_fetch%]",
+            "web_fetch_max_uses": "[%key:component::anthropic::config_subentries::conversation::step::model::data::web_fetch_max_uses%]",
             "web_search": "[%key:component::anthropic::config_subentries::conversation::step::model::data::web_search%]",
             "web_search_max_uses": "[%key:component::anthropic::config_subentries::conversation::step::model::data::web_search_max_uses%]"
           },
@@ -90,6 +92,8 @@
             "thinking_effort": "[%key:component::anthropic::config_subentries::conversation::step::model::data_description::thinking_effort%]",
             "tool_search": "[%key:component::anthropic::config_subentries::conversation::step::model::data_description::tool_search%]",
             "user_location": "[%key:component::anthropic::config_subentries::conversation::step::model::data_description::user_location%]",
+            "web_fetch": "[%key:component::anthropic::config_subentries::conversation::step::model::data_description::web_fetch%]",
+            "web_fetch_max_uses": "[%key:component::anthropic::config_subentries::conversation::step::model::data_description::web_fetch_max_uses%]",
             "web_search": "[%key:component::anthropic::config_subentries::conversation::step::model::data_description::web_search%]",
             "web_search_max_uses": "[%key:component::anthropic::config_subentries::conversation::step::model::data_description::web_search_max_uses%]"
           },
@@ -149,6 +153,8 @@
             "thinking_effort": "Thinking effort",
             "tool_search": "Enable tool search tool",
             "user_location": "Include home location",
+            "web_fetch": "Enable web fetch",
+            "web_fetch_max_uses": "Maximum web fetches",
             "web_search": "Enable web search",
             "web_search_max_uses": "Maximum web searches"
           },
@@ -159,6 +165,8 @@
             "thinking_effort": "Control how many tokens Claude uses when responding, trading off between response thoroughness and token efficiency",
             "tool_search": "Enable dynamic tool discovery instead of preloading all tools into the context",
             "user_location": "Localize search results based on home location",
+            "web_fetch": "The web fetch tool allows Claude to retrieve full content from specified web pages and PDF documents to augment Claude's context with live web content",
+            "web_fetch_max_uses": "Limit the number of web fetches performed per response",
             "web_search": "The web search tool gives Claude direct access to real-time web content, allowing it to answer questions with up-to-date information beyond its knowledge cutoff",
             "web_search_max_uses": "Limit the number of searches performed per response"
           },

tests/components/anthropic/__init__.py

@@ -36,6 +36,7 @@
     ThinkingTypes,
     ToolSearchToolResultBlock,
     ToolUseBlock,
+    WebFetchToolResultBlock,
     WebSearchResultBlock,
     WebSearchToolResultBlock,
     WebSearchToolResultError,
@@ -47,6 +48,9 @@
 from anthropic.types.tool_search_tool_result_block import (
     Content as ToolSearchToolResultBlockContent,
 )
+from anthropic.types.web_fetch_tool_result_block import (
+    Content as WebFetchToolResultBlockContent,
+)
 
 model_list = [
     ModelInfo(
@@ -641,3 +645,28 @@ def create_tool_search_result_block(
         ),
         RawContentBlockStopEvent(index=index, type="content_block_stop"),
     ]
+
+
+def create_web_fetch_result_block(
+    index: int,
+    id: str,
+    results: WebFetchToolResultBlockContent,
+    caller: Caller | None = None,
+) -> list[RawMessageStreamEvent]:
+    """Create a server tool result block for web fetch results."""
+    if caller is None:
+        caller = DirectCaller(type="direct")
+
+    return [
+        RawContentBlockStartEvent(
+            type="content_block_start",
+            content_block=WebFetchToolResultBlock(
+                type="web_fetch_tool_result",
+                tool_use_id=id,
+                content=results,
+                caller=caller,
+            ),
+            index=index,
+        ),
+        RawContentBlockStopEvent(index=index, type="content_block_stop"),
+    ]