feat(citations): Add support for web and search result citations

Add support for web-based and search result citations in the Bedrock
Converse API, enabling the SDK to handle all citation location types.

Changes:
- Add WebLocation and WebLocationInner types for web citations
- Add SearchResultLocation and SearchResultLocationInner types
- Update _format_citation_location to handle web and searchResultLocation
- Add tests for web and search result citation types

This completes support for all CitationLocation types as per the
Bedrock Converse API specification.

Author: Danilo Poccia

src/strands/models/bedrock.py

@@ -543,7 +543,8 @@ def _format_citation_location(self, location: Mapping[str, Any]) -> dict[str, An
         """Format a citation location preserving the tagged union structure.
 
         The Bedrock API requires CitationLocation to be a tagged union with exactly one
-        of the following keys: documentChar, documentPage, or documentChunk.
+        of the following keys: web, documentChar, documentPage, documentChunk, or
+        searchResultLocation.
 
         Args:
             location: Citation location to format.
@@ -556,9 +557,11 @@ def _format_citation_location(self, location: Mapping[str, Any]) -> dict[str, An
         """
         # Allowed fields for each tagged union type
         allowed_fields = {
+            "web": ("url", "domain"),
             "documentChar": ("documentIndex", "start", "end"),
             "documentPage": ("documentIndex", "start", "end"),
             "documentChunk": ("documentIndex", "start", "end"),
+            "searchResultLocation": ("searchResultIndex", "start", "end"),
         }
 
         for location_type, fields in allowed_fields.items():

src/strands/types/citations.py

@@ -70,6 +70,35 @@ class DocumentPageLocationInner(TypedDict, total=False):
     end: int
 
 
+class WebLocationInner(TypedDict, total=False):
+    """Inner content for web-based location.
+
+    Attributes:
+        url: The URL of the web page containing the cited content.
+        domain: The domain of the web page containing the cited content.
+    """
+
+    url: str
+    domain: str
+
+
+class SearchResultLocationInner(TypedDict, total=False):
+    """Inner content for search result location.
+
+    Attributes:
+        searchResultIndex: The index of the search result content block where
+            the cited content is found. Minimum value of 0.
+        start: The starting position in the content array where the cited
+            content begins. Minimum value of 0.
+        end: The ending position in the content array where the cited
+            content ends. Minimum value of 0.
+    """
+
+    searchResultIndex: int
+    start: int
+    end: int
+
+
 class DocumentCharLocation(TypedDict, total=False):
     """Tagged union wrapper for character-level document location.
 
@@ -100,8 +129,30 @@ class DocumentPageLocation(TypedDict, total=False):
     documentPage: DocumentPageLocationInner
 
 
+class WebLocation(TypedDict, total=False):
+    """Tagged union wrapper for web-based location.
+
+    Attributes:
+        web: The web location data.
+    """
+
+    web: WebLocationInner
+
+
+class SearchResultLocation(TypedDict, total=False):
+    """Tagged union wrapper for search result location.
+
+    Attributes:
+        searchResultLocation: The search result location data.
+    """
+
+    searchResultLocation: SearchResultLocationInner
+
+
 # Union type for citation locations - tagged union where exactly one key is present
-CitationLocation = Union[DocumentCharLocation, DocumentChunkLocation, DocumentPageLocation]
+CitationLocation = Union[
+    DocumentCharLocation, DocumentChunkLocation, DocumentPageLocation, WebLocation, SearchResultLocation
+]
 
 
 class CitationSourceContent(TypedDict, total=False):

tests/strands/models/test_bedrock.py

@@ -2173,3 +2173,69 @@ def test_format_request_message_content_citation_unknown_location_type(model):
     result = model._format_request_message_content(content)
 
     assert "location" not in result["citationsContent"]["citations"][0]
+
+
+def test_format_request_message_content_web_citation(model):
+    """Test that web citations preserve tagged union structure."""
+    content = {
+        "citationsContent": {
+            "citations": [
+                {
+                    "title": "Web Citation",
+                    "location": {"web": {"url": "https://example.com", "domain": "example.com"}},
+                    "sourceContent": [{"text": "Web content"}],
+                }
+            ],
+            "content": [{"text": "Generated text"}],
+        }
+    }
+
+    result = model._format_request_message_content(content)
+
+    assert result["citationsContent"]["citations"][0]["location"] == {
+        "web": {"url": "https://example.com", "domain": "example.com"}
+    }
+
+
+def test_format_request_message_content_web_citation_filters_extra_fields(model):
+    """Test that extra fields in web citation location are filtered out."""
+    content = {
+        "citationsContent": {
+            "citations": [
+                {
+                    "title": "Web Citation",
+                    "location": {"web": {"url": "https://example.com", "domain": "example.com", "extra": "ignored"}},
+                    "sourceContent": [{"text": "Content"}],
+                }
+            ],
+            "content": [{"text": "Text"}],
+        }
+    }
+
+    result = model._format_request_message_content(content)
+
+    assert result["citationsContent"]["citations"][0]["location"] == {
+        "web": {"url": "https://example.com", "domain": "example.com"}
+    }
+
+
+def test_format_request_message_content_search_result_citation(model):
+    """Test that searchResultLocation citations preserve tagged union structure."""
+    content = {
+        "citationsContent": {
+            "citations": [
+                {
+                    "title": "Search Citation",
+                    "location": {"searchResultLocation": {"searchResultIndex": 1, "start": 0, "end": 50}},
+                    "sourceContent": [{"text": "Search result"}],
+                }
+            ],
+            "content": [{"text": "Generated text"}],
+        }
+    }
+
+    result = model._format_request_message_content(content)
+
+    assert result["citationsContent"]["citations"][0]["location"] == {
+        "searchResultLocation": {"searchResultIndex": 1, "start": 0, "end": 50}
+    }