diff --git a/models/spring-ai-anthropic/src/main/java/org/springframework/ai/anthropic/AnthropicChatModel.java b/models/spring-ai-anthropic/src/main/java/org/springframework/ai/anthropic/AnthropicChatModel.java
index d2960ddb935..da8324eb409 100644
--- a/models/spring-ai-anthropic/src/main/java/org/springframework/ai/anthropic/AnthropicChatModel.java
+++ b/models/spring-ai-anthropic/src/main/java/org/springframework/ai/anthropic/AnthropicChatModel.java
@@ -44,6 +44,7 @@
 import org.springframework.ai.anthropic.api.AnthropicApi.Role;
 import org.springframework.ai.anthropic.api.AnthropicCacheOptions;
 import org.springframework.ai.anthropic.api.AnthropicCacheTtl;
+import org.springframework.ai.anthropic.api.CitationDocument;
 import org.springframework.ai.anthropic.api.utils.CacheEligibilityResolver;
 import org.springframework.ai.chat.messages.AssistantMessage;
 import org.springframework.ai.chat.messages.Message;
@@ -322,12 +323,13 @@ private ChatResponse toChatResponse(ChatCompletionResponse chatCompletion, Usage
 
 		List<Generation> generations = new ArrayList<>();
 		List<AssistantMessage.ToolCall> toolCalls = new ArrayList<>();
+		CitationContext citationContext = new CitationContext();
 		for (ContentBlock content : chatCompletion.content()) {
 			switch (content.type()) {
 				case TEXT, TEXT_DELTA:
-					generations.add(new Generation(
-							AssistantMessage.builder().content(content.text()).properties(Map.of()).build(),
-							ChatGenerationMetadata.builder().finishReason(chatCompletion.stopReason()).build()));
+					Generation textGeneration = processTextContent(content, chatCompletion.stopReason(),
+							citationContext);
+					generations.add(textGeneration);
 					break;
 				case THINKING, THINKING_DELTA:
 					Map<String, Object> thinkingProperties = new HashMap<>();
@@ -371,7 +373,101 @@ private ChatResponse toChatResponse(ChatCompletionResponse chatCompletion, Usage
 					ChatGenerationMetadata.builder().finishReason(chatCompletion.stopReason()).build());
 			generations.add(toolCallGeneration);
 		}
-		return new ChatResponse(generations, this.from(chatCompletion, usage));
+
+		// Create response metadata with citation information if present
+		ChatResponseMetadata.Builder metadataBuilder = ChatResponseMetadata.builder()
+			.id(chatCompletion.id())
+			.model(chatCompletion.model())
+			.usage(usage)
+			.keyValue("stop-reason", chatCompletion.stopReason())
+			.keyValue("stop-sequence", chatCompletion.stopSequence())
+			.keyValue("type", chatCompletion.type());
+
+		// Add citation metadata if citations were found
+		if (citationContext.hasCitations()) {
+			metadataBuilder.keyValue("citations", citationContext.getAllCitations())
+				.keyValue("citationCount", citationContext.getTotalCitationCount());
+		}
+
+		ChatResponseMetadata responseMetadata = metadataBuilder.build();
+
+		return new ChatResponse(generations, responseMetadata);
+	}
+
+	private Generation processTextContent(ContentBlock content, String stopReason, CitationContext citationContext) {
+		// Extract citations if present in the content block
+		if (content.citations() instanceof List) {
+			try {
+				@SuppressWarnings("unchecked")
+				List<Object> citationObjects = (List<Object>) content.citations();
+
+				List<Citation> citations = new ArrayList<>();
+				for (Object citationObj : citationObjects) {
+					if (citationObj instanceof Map) {
+						// Convert Map to CitationResponse using manual parsing
+						AnthropicApi.CitationResponse citationResponse = parseCitationFromMap((Map<?, ?>) citationObj);
+						citations.add(convertToCitation(citationResponse));
+					}
+					else {
+						logger.warn("Unexpected citation object type: {}. Expected Map but got: {}. Skipping citation.",
+								citationObj.getClass().getName(), citationObj);
+					}
+				}
+
+				if (!citations.isEmpty()) {
+					citationContext.addCitations(citations);
+				}
+
+			}
+			catch (Exception e) {
+				logger.warn("Failed to parse citations from content block", e);
+			}
+		}
+
+		return new Generation(new AssistantMessage(content.text()),
+				ChatGenerationMetadata.builder().finishReason(stopReason).build());
+	}
+
+	/**
+	 * Parse citation data from Map (typically from JSON deserialization). Assumes all
+	 * required fields are present and of correct types.
+	 * @param citationMap the map containing citation data from API response
+	 * @return parsed CitationResponse
+	 */
+	private AnthropicApi.CitationResponse parseCitationFromMap(Map<?, ?> citationMap) {
+		String type = (String) citationMap.get("type");
+		String citedText = (String) citationMap.get("cited_text");
+		Integer documentIndex = (Integer) citationMap.get("document_index");
+		String documentTitle = (String) citationMap.get("document_title");
+
+		Integer startCharIndex = (Integer) citationMap.get("start_char_index");
+		Integer endCharIndex = (Integer) citationMap.get("end_char_index");
+		Integer startPageNumber = (Integer) citationMap.get("start_page_number");
+		Integer endPageNumber = (Integer) citationMap.get("end_page_number");
+		Integer startBlockIndex = (Integer) citationMap.get("start_block_index");
+		Integer endBlockIndex = (Integer) citationMap.get("end_block_index");
+
+		return new AnthropicApi.CitationResponse(type, citedText, documentIndex, documentTitle, startCharIndex,
+				endCharIndex, startPageNumber, endPageNumber, startBlockIndex, endBlockIndex);
+	}
+
+	/**
+	 * Convert CitationResponse to Citation object. This method handles the conversion to
+	 * avoid circular dependencies.
+	 */
+	private Citation convertToCitation(AnthropicApi.CitationResponse citationResponse) {
+		return switch (citationResponse.type()) {
+			case "char_location" -> Citation.ofCharLocation(citationResponse.citedText(),
+					citationResponse.documentIndex(), citationResponse.documentTitle(),
+					citationResponse.startCharIndex(), citationResponse.endCharIndex());
+			case "page_location" -> Citation.ofPageLocation(citationResponse.citedText(),
+					citationResponse.documentIndex(), citationResponse.documentTitle(),
+					citationResponse.startPageNumber(), citationResponse.endPageNumber());
+			case "content_block_location" -> Citation.ofContentBlockLocation(citationResponse.citedText(),
+					citationResponse.documentIndex(), citationResponse.documentTitle(),
+					citationResponse.startBlockIndex(), citationResponse.endBlockIndex());
+			default -> throw new IllegalArgumentException("Unknown citation type: " + citationResponse.type());
+		};
 	}
 
 	private ChatResponseMetadata from(AnthropicApi.ChatCompletionResponse result) {
@@ -479,6 +575,14 @@ Prompt buildRequestPrompt(Prompt prompt) {
 			// Merge cache options that are Json-ignored
 			requestOptions.setCacheOptions(runtimeOptions.getCacheOptions() != null ? runtimeOptions.getCacheOptions()
 					: this.defaultOptions.getCacheOptions());
+
+			// Merge citation documents that are Json-ignored
+			if (runtimeOptions.getCitationDocuments() != null && !runtimeOptions.getCitationDocuments().isEmpty()) {
+				requestOptions.setCitationDocuments(runtimeOptions.getCitationDocuments());
+			}
+			else if (this.defaultOptions.getCitationDocuments() != null) {
+				requestOptions.setCitationDocuments(this.defaultOptions.getCitationDocuments());
+			}
 		}
 		else {
 			requestOptions.setHttpHeaders(this.defaultOptions.getHttpHeaders());
@@ -486,6 +590,7 @@ Prompt buildRequestPrompt(Prompt prompt) {
 			requestOptions.setToolNames(this.defaultOptions.getToolNames());
 			requestOptions.setToolCallbacks(this.defaultOptions.getToolCallbacks());
 			requestOptions.setToolContext(this.defaultOptions.getToolContext());
+			requestOptions.setCitationDocuments(this.defaultOptions.getCitationDocuments());
 		}
 
 		ToolCallingChatOptions.validateToolCallbacks(requestOptions.getToolCallbacks());
@@ -610,12 +715,24 @@ private List<AnthropicMessage> buildMessages(Prompt prompt, CacheEligibilityReso
 			}
 		}
 
+		// Get citation documents from options
+		List<CitationDocument> citationDocuments = null;
+		if (prompt.getOptions() instanceof AnthropicChatOptions anthropicOptions) {
+			citationDocuments = anthropicOptions.getCitationDocuments();
+		}
+
 		List<AnthropicMessage> result = new ArrayList<>();
 		for (int i = 0; i < allMessages.size(); i++) {
 			Message message = allMessages.get(i);
 			MessageType messageType = message.getMessageType();
 			if (messageType == MessageType.USER) {
 				List<ContentBlock> contentBlocks = new ArrayList<>();
+				// Add citation documents to the FIRST user message only
+				if (i == 0 && citationDocuments != null && !citationDocuments.isEmpty()) {
+					for (CitationDocument doc : citationDocuments) {
+						contentBlocks.add(doc.toContentBlock());
+					}
+				}
 				String content = message.getText();
 				// For conversation history caching, apply cache control to the
 				// message immediately before the last user message.
@@ -823,4 +940,30 @@ public AnthropicChatModel build() {
 
 	}
 
+	/**
+	 * Context object for tracking citations during response processing. Aggregates
+	 * citations from multiple content blocks in a single response.
+	 */
+	class CitationContext {
+
+		private final List<Citation> allCitations = new ArrayList<>();
+
+		public void addCitations(List<Citation> citations) {
+			this.allCitations.addAll(citations);
+		}
+
+		public boolean hasCitations() {
+			return !this.allCitations.isEmpty();
+		}
+
+		public List<Citation> getAllCitations() {
+			return new ArrayList<>(this.allCitations);
+		}
+
+		public int getTotalCitationCount() {
+			return this.allCitations.size();
+		}
+
+	}
+
 }
diff --git a/models/spring-ai-anthropic/src/main/java/org/springframework/ai/anthropic/AnthropicChatOptions.java b/models/spring-ai-anthropic/src/main/java/org/springframework/ai/anthropic/AnthropicChatOptions.java
index 0b83d3275a5..8061bb71e42 100644
--- a/models/spring-ai-anthropic/src/main/java/org/springframework/ai/anthropic/AnthropicChatOptions.java
+++ b/models/spring-ai-anthropic/src/main/java/org/springframework/ai/anthropic/AnthropicChatOptions.java
@@ -33,6 +33,7 @@
 import org.springframework.ai.anthropic.api.AnthropicApi;
 import org.springframework.ai.anthropic.api.AnthropicApi.ChatCompletionRequest;
 import org.springframework.ai.anthropic.api.AnthropicCacheOptions;
+import org.springframework.ai.anthropic.api.CitationDocument;
 import org.springframework.ai.model.tool.ToolCallingChatOptions;
 import org.springframework.ai.tool.ToolCallback;
 import org.springframework.lang.Nullable;
@@ -63,6 +64,17 @@ public class AnthropicChatOptions implements ToolCallingChatOptions {
 	private @JsonProperty("tool_choice") AnthropicApi.ToolChoice toolChoice;
 	private @JsonProperty("thinking") ChatCompletionRequest.ThinkingConfig thinking;
 
+	/**
+	 * Documents to be used for citation-based responses. These documents will be
+	 * converted to ContentBlocks and included in the first user message of the request.
+	 * Citations indicating which parts of these documents were used in the response will
+	 * be returned in the response metadata under the "citations" key.
+	 * @see CitationDocument
+	 * @see Citation
+	 */
+	@JsonIgnore
+	private List<CitationDocument> citationDocuments = new ArrayList<>();
+
 	@JsonIgnore
 	private AnthropicCacheOptions cacheOptions = AnthropicCacheOptions.DISABLED;
 
@@ -127,6 +139,8 @@ public static AnthropicChatOptions fromOptions(AnthropicChatOptions fromOptions)
 			.toolContext(fromOptions.getToolContext() != null ? new HashMap<>(fromOptions.getToolContext()) : null)
 			.httpHeaders(fromOptions.getHttpHeaders() != null ? new HashMap<>(fromOptions.getHttpHeaders()) : null)
 			.cacheOptions(fromOptions.getCacheOptions())
+			.citationDocuments(fromOptions.getCitationDocuments() != null
+					? new ArrayList<>(fromOptions.getCitationDocuments()) : null)
 			.build();
 	}
 
@@ -283,6 +297,34 @@ public void setHttpHeaders(Map<String, String> httpHeaders) {
 		this.httpHeaders = httpHeaders;
 	}
 
+	public List<CitationDocument> getCitationDocuments() {
+		return this.citationDocuments;
+	}
+
+	public void setCitationDocuments(List<CitationDocument> citationDocuments) {
+		Assert.notNull(citationDocuments, "Citation documents cannot be null");
+		this.citationDocuments = citationDocuments;
+	}
+
+	/**
+	 * Validate that all citation documents have consistent citation settings. Anthropic
+	 * requires all documents to have citations enabled if any do.
+	 */
+	public void validateCitationConsistency() {
+		if (this.citationDocuments.isEmpty()) {
+			return;
+		}
+
+		boolean hasEnabledCitations = this.citationDocuments.stream().anyMatch(CitationDocument::isCitationsEnabled);
+		boolean hasDisabledCitations = this.citationDocuments.stream().anyMatch(doc -> !doc.isCitationsEnabled());
+
+		if (hasEnabledCitations && hasDisabledCitations) {
+			throw new IllegalArgumentException(
+					"Anthropic Citations API requires all documents to have consistent citation settings. "
+							+ "Either enable citations for all documents or disable for all documents.");
+		}
+	}
+
 	@Override
 	@SuppressWarnings("unchecked")
 	public AnthropicChatOptions copy() {
@@ -308,14 +350,16 @@ public boolean equals(Object o) {
 				&& Objects.equals(this.internalToolExecutionEnabled, that.internalToolExecutionEnabled)
 				&& Objects.equals(this.toolContext, that.toolContext)
 				&& Objects.equals(this.httpHeaders, that.httpHeaders)
-				&& Objects.equals(this.cacheOptions, that.cacheOptions);
+				&& Objects.equals(this.cacheOptions, that.cacheOptions)
+				&& Objects.equals(this.citationDocuments, that.citationDocuments);
 	}
 
 	@Override
 	public int hashCode() {
 		return Objects.hash(this.model, this.maxTokens, this.metadata, this.stopSequences, this.temperature, this.topP,
 				this.topK, this.toolChoice, this.thinking, this.toolCallbacks, this.toolNames,
-				this.internalToolExecutionEnabled, this.toolContext, this.httpHeaders, this.cacheOptions);
+				this.internalToolExecutionEnabled, this.toolContext, this.httpHeaders, this.cacheOptions,
+				this.citationDocuments);
 	}
 
 	public static final class Builder {
@@ -425,7 +469,40 @@ public Builder cacheOptions(AnthropicCacheOptions cacheOptions) {
 			return this;
 		}
 
+		/**
+		 * Set citation documents for the request.
+		 * @param citationDocuments List of documents to include for citations
+		 * @return Builder for method chaining
+		 */
+		public Builder citationDocuments(List<CitationDocument> citationDocuments) {
+			this.options.setCitationDocuments(citationDocuments);
+			return this;
+		}
+
+		/**
+		 * Set citation documents from variable arguments.
+		 * @param documents Variable number of CitationDocument objects
+		 * @return Builder for method chaining
+		 */
+		public Builder citationDocuments(CitationDocument... documents) {
+			Assert.notNull(documents, "Citation documents cannot be null");
+			this.options.citationDocuments.addAll(Arrays.asList(documents));
+			return this;
+		}
+
+		/**
+		 * Add a single citation document.
+		 * @param document Citation document to add
+		 * @return Builder for method chaining
+		 */
+		public Builder addCitationDocument(CitationDocument document) {
+			Assert.notNull(document, "Citation document cannot be null");
+			this.options.citationDocuments.add(document);
+			return this;
+		}
+
 		public AnthropicChatOptions build() {
+			this.options.validateCitationConsistency();
 			return this.options;
 		}
 
diff --git a/models/spring-ai-anthropic/src/main/java/org/springframework/ai/anthropic/Citation.java b/models/spring-ai-anthropic/src/main/java/org/springframework/ai/anthropic/Citation.java
new file mode 100644
index 00000000000..1a7a8b06989
--- /dev/null
+++ b/models/spring-ai-anthropic/src/main/java/org/springframework/ai/anthropic/Citation.java
@@ -0,0 +1,223 @@
+/*
+ * Copyright 2023-2025 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.ai.anthropic;
+
+import org.springframework.ai.anthropic.api.CitationDocument;
+
+/**
+ * Represents a citation reference in a Claude response. Citations indicate which parts of
+ * the provided documents were referenced when generating the response.
+ *
+ * <p>
+ * Citations are returned in the response metadata under the "citations" key and include:
+ * <ul>
+ * <li>The cited text from the document</li>
+ * <li>The document index (which document was cited)</li>
+ * <li>The document title (if provided)</li>
+ * <li>Location information (character ranges, page numbers, or content block
+ * indices)</li>
+ * </ul>
+ *
+ * <h3>Citation Types</h3>
+ * <ul>
+ * <li><b>CHAR_LOCATION:</b> For plain text documents, includes character start/end
+ * indices</li>
+ * <li><b>PAGE_LOCATION:</b> For PDF documents, includes page start/end numbers</li>
+ * <li><b>CONTENT_BLOCK_LOCATION:</b> For custom content documents, includes block
+ * start/end indices</li>
+ * </ul>
+ *
+ * <h3>Example Usage</h3>
+ *
+ * <pre>{@code
+ * ChatResponse response = chatModel.call(prompt);
+ *
+ * List<Citation> citations = (List<Citation>) response.getMetadata().get("citations");
+ *
+ * for (Citation citation : citations) {
+ *     System.out.println("Document: " + citation.getDocumentTitle());
+ *     System.out.println("Location: " + citation.getLocationDescription());
+ *     System.out.println("Text: " + citation.getCitedText());
+ * }
+ * }</pre>
+ *
+ * @author Soby Chacko
+ * @since 1.1.0
+ * @see CitationDocument
+ */
+public final class Citation {
+
+	/**
+	 * Types of citation locations based on document format.
+	 */
+	public enum LocationType {
+
+		/** Character-based location for plain text documents */
+		CHAR_LOCATION,
+
+		/** Page-based location for PDF documents */
+		PAGE_LOCATION,
+
+		/** Block-based location for custom content documents */
+		CONTENT_BLOCK_LOCATION
+
+	}
+
+	private final LocationType type;
+
+	private final String citedText;
+
+	private final int documentIndex;
+
+	private final String documentTitle;
+
+	// Location-specific fields
+	private Integer startCharIndex;
+
+	private Integer endCharIndex;
+
+	private Integer startPageNumber;
+
+	private Integer endPageNumber;
+
+	private Integer startBlockIndex;
+
+	private Integer endBlockIndex;
+
+	// Private constructor
+	private Citation(LocationType type, String citedText, int documentIndex, String documentTitle) {
+		this.type = type;
+		this.citedText = citedText;
+		this.documentIndex = documentIndex;
+		this.documentTitle = documentTitle;
+	}
+
+	/**
+	 * Create a character location citation for plain text documents.
+	 * @param citedText the text that was cited from the document
+	 * @param documentIndex the index of the document (0-based)
+	 * @param documentTitle the title of the document
+	 * @param startCharIndex the starting character index (0-based, inclusive)
+	 * @param endCharIndex the ending character index (exclusive)
+	 * @return a new Citation with CHAR_LOCATION type
+	 */
+	public static Citation ofCharLocation(String citedText, int documentIndex, String documentTitle, int startCharIndex,
+			int endCharIndex) {
+		Citation citation = new Citation(LocationType.CHAR_LOCATION, citedText, documentIndex, documentTitle);
+		citation.startCharIndex = startCharIndex;
+		citation.endCharIndex = endCharIndex;
+		return citation;
+	}
+
+	/**
+	 * Create a page location citation for PDF documents.
+	 * @param citedText the text that was cited from the document
+	 * @param documentIndex the index of the document (0-based)
+	 * @param documentTitle the title of the document
+	 * @param startPageNumber the starting page number (1-based, inclusive)
+	 * @param endPageNumber the ending page number (exclusive)
+	 * @return a new Citation with PAGE_LOCATION type
+	 */
+	public static Citation ofPageLocation(String citedText, int documentIndex, String documentTitle,
+			int startPageNumber, int endPageNumber) {
+		Citation citation = new Citation(LocationType.PAGE_LOCATION, citedText, documentIndex, documentTitle);
+		citation.startPageNumber = startPageNumber;
+		citation.endPageNumber = endPageNumber;
+		return citation;
+	}
+
+	/**
+	 * Create a content block location citation for custom content documents.
+	 * @param citedText the text that was cited from the document
+	 * @param documentIndex the index of the document (0-based)
+	 * @param documentTitle the title of the document
+	 * @param startBlockIndex the starting content block index (0-based, inclusive)
+	 * @param endBlockIndex the ending content block index (exclusive)
+	 * @return a new Citation with CONTENT_BLOCK_LOCATION type
+	 */
+	public static Citation ofContentBlockLocation(String citedText, int documentIndex, String documentTitle,
+			int startBlockIndex, int endBlockIndex) {
+		Citation citation = new Citation(LocationType.CONTENT_BLOCK_LOCATION, citedText, documentIndex, documentTitle);
+		citation.startBlockIndex = startBlockIndex;
+		citation.endBlockIndex = endBlockIndex;
+		return citation;
+	}
+
+	public LocationType getType() {
+		return this.type;
+	}
+
+	public String getCitedText() {
+		return this.citedText;
+	}
+
+	public int getDocumentIndex() {
+		return this.documentIndex;
+	}
+
+	public String getDocumentTitle() {
+		return this.documentTitle;
+	}
+
+	public Integer getStartCharIndex() {
+		return this.startCharIndex;
+	}
+
+	public Integer getEndCharIndex() {
+		return this.endCharIndex;
+	}
+
+	public Integer getStartPageNumber() {
+		return this.startPageNumber;
+	}
+
+	public Integer getEndPageNumber() {
+		return this.endPageNumber;
+	}
+
+	public Integer getStartBlockIndex() {
+		return this.startBlockIndex;
+	}
+
+	public Integer getEndBlockIndex() {
+		return this.endBlockIndex;
+	}
+
+	/**
+	 * Get a human-readable location description.
+	 */
+	public String getLocationDescription() {
+		return switch (this.type) {
+			case CHAR_LOCATION -> String.format("Characters %d-%d", this.startCharIndex, this.endCharIndex);
+			case PAGE_LOCATION ->
+				this.startPageNumber.equals(this.endPageNumber - 1) ? String.format("Page %d", this.startPageNumber)
+						: String.format("Pages %d-%d", this.startPageNumber, this.endPageNumber - 1);
+			case CONTENT_BLOCK_LOCATION ->
+				this.startBlockIndex.equals(this.endBlockIndex - 1) ? String.format("Block %d", this.startBlockIndex)
+						: String.format("Blocks %d-%d", this.startBlockIndex, this.endBlockIndex - 1);
+		};
+	}
+
+	@Override
+	public String toString() {
+		return String.format("Citation{type=%s, documentIndex=%d, documentTitle='%s', location='%s', citedText='%s'}",
+				this.type, this.documentIndex, this.documentTitle, getLocationDescription(),
+				this.citedText != null && this.citedText.length() > 50 ? this.citedText.substring(0, 50) + "..."
+						: this.citedText);
+	}
+
+}
diff --git a/models/spring-ai-anthropic/src/main/java/org/springframework/ai/anthropic/api/AnthropicApi.java b/models/spring-ai-anthropic/src/main/java/org/springframework/ai/anthropic/api/AnthropicApi.java
index cdd1a4fef51..cc18d7cb717 100644
--- a/models/spring-ai-anthropic/src/main/java/org/springframework/ai/anthropic/api/AnthropicApi.java
+++ b/models/spring-ai-anthropic/src/main/java/org/springframework/ai/anthropic/api/AnthropicApi.java
@@ -753,6 +753,53 @@ public record AnthropicMessage(
 		// @formatter:on
 	}
 
+	/**
+	 * Citations configuration for document ContentBlocks.
+	 */
+	@JsonInclude(Include.NON_NULL)
+	public record CitationsConfig(@JsonProperty("enabled") Boolean enabled) {
+	}
+
+	/**
+	 * Citation response structure from Anthropic API. Maps to the actual API response
+	 * format for citations. Contains location information that varies by document type:
+	 * character indices for plain text, page numbers for PDFs, or content block indices
+	 * for custom content.
+	 *
+	 * @param type The citation location type ("char_location", "page_location", or
+	 * "content_block_location")
+	 * @param citedText The text that was cited from the document
+	 * @param documentIndex The index of the document that was cited (0-based)
+	 * @param documentTitle The title of the document that was cited
+	 * @param startCharIndex The starting character index for "char_location" type
+	 * (0-based, inclusive)
+	 * @param endCharIndex The ending character index for "char_location" type (exclusive)
+	 * @param startPageNumber The starting page number for "page_location" type (1-based,
+	 * inclusive)
+	 * @param endPageNumber The ending page number for "page_location" type (exclusive)
+	 * @param startBlockIndex The starting content block index for
+	 * "content_block_location" type (0-based, inclusive)
+	 * @param endBlockIndex The ending content block index for "content_block_location"
+	 * type (exclusive)
+	 */
+	@JsonInclude(Include.NON_NULL)
+	@JsonIgnoreProperties(ignoreUnknown = true)
+	public record CitationResponse(@JsonProperty("type") String type, @JsonProperty("cited_text") String citedText,
+			@JsonProperty("document_index") Integer documentIndex, @JsonProperty("document_title") String documentTitle,
+
+			// For char_location type
+			@JsonProperty("start_char_index") Integer startCharIndex,
+			@JsonProperty("end_char_index") Integer endCharIndex,
+
+			// For page_location type
+			@JsonProperty("start_page_number") Integer startPageNumber,
+			@JsonProperty("end_page_number") Integer endPageNumber,
+
+			// For content_block_location type
+			@JsonProperty("start_block_index") Integer startBlockIndex,
+			@JsonProperty("end_block_index") Integer endBlockIndex) {
+	}
+
 	/**
 	 * The content block of the message.
 	 *
@@ -797,7 +844,12 @@ public record ContentBlock(
 		@JsonProperty("data") String data,
 
 		// cache object
-		@JsonProperty("cache_control") CacheControl cacheControl
+		@JsonProperty("cache_control") CacheControl cacheControl,
+
+		// Citation fields
+		@JsonProperty("title") String title,
+		@JsonProperty("context") String context,
+		@JsonProperty("citations") Object citations // Can be CitationsConfig for requests or List<CitationResponse> for responses
 	) {
 		// @formatter:on
 
@@ -816,7 +868,7 @@ public ContentBlock(String mediaType, String data) {
 		 * @param source The source of the content.
 		 */
 		public ContentBlock(Type type, Source source) {
-			this(type, source, null, null, null, null, null, null, null, null, null, null, null);
+			this(type, source, null, null, null, null, null, null, null, null, null, null, null, null, null, null);
 		}
 
 		/**
@@ -824,7 +876,8 @@ public ContentBlock(Type type, Source source) {
 		 * @param source The source of the content.
 		 */
 		public ContentBlock(Source source) {
-			this(Type.IMAGE, source, null, null, null, null, null, null, null, null, null, null, null);
+			this(Type.IMAGE, source, null, null, null, null, null, null, null, null, null, null, null, null, null,
+					null);
 		}
 
 		/**
@@ -832,11 +885,11 @@ public ContentBlock(Source source) {
 		 * @param text The text of the content.
 		 */
 		public ContentBlock(String text) {
-			this(Type.TEXT, null, text, null, null, null, null, null, null, null, null, null, null);
+			this(Type.TEXT, null, text, null, null, null, null, null, null, null, null, null, null, null, null, null);
 		}
 
 		public ContentBlock(String text, CacheControl cache) {
-			this(Type.TEXT, null, text, null, null, null, null, null, null, null, null, null, cache);
+			this(Type.TEXT, null, text, null, null, null, null, null, null, null, null, null, cache, null, null, null);
 		}
 
 		// Tool result
@@ -847,7 +900,8 @@ public ContentBlock(String text, CacheControl cache) {
 		 * @param content The content of the tool result.
 		 */
 		public ContentBlock(Type type, String toolUseId, String content) {
-			this(type, null, null, null, null, null, null, toolUseId, content, null, null, null, null);
+			this(type, null, null, null, null, null, null, toolUseId, content, null, null, null, null, null, null,
+					null);
 		}
 
 		/**
@@ -858,7 +912,7 @@ public ContentBlock(Type type, String toolUseId, String content) {
 		 * @param index The index of the content block.
 		 */
 		public ContentBlock(Type type, Source source, String text, Integer index) {
-			this(type, source, text, index, null, null, null, null, null, null, null, null, null);
+			this(type, source, text, index, null, null, null, null, null, null, null, null, null, null, null, null);
 		}
 
 		// Tool use input JSON delta streaming
@@ -870,7 +924,21 @@ public ContentBlock(Type type, Source source, String text, Integer index) {
 		 * @param input The input of the tool use.
 		 */
 		public ContentBlock(Type type, String id, String name, Map<String, Object> input) {
-			this(type, null, null, null, id, name, input, null, null, null, null, null, null);
+			this(type, null, null, null, id, name, input, null, null, null, null, null, null, null, null, null);
+		}
+
+		/**
+		 * Create a document ContentBlock with citations and optional caching.
+		 * @param source The document source
+		 * @param title Optional document title
+		 * @param context Optional document context
+		 * @param citationsEnabled Whether citations are enabled
+		 * @param cacheControl Optional cache control (can be null)
+		 */
+		public ContentBlock(Source source, String title, String context, boolean citationsEnabled,
+				CacheControl cacheControl) {
+			this(Type.DOCUMENT, source, null, null, null, null, null, null, null, null, null, null, cacheControl, title,
+					context, citationsEnabled ? new CitationsConfig(true) : null);
 		}
 
 		public static ContentBlockBuilder from(ContentBlock contentBlock) {
@@ -983,7 +1051,8 @@ public record Source(
 			@JsonProperty("type") String type,
 			@JsonProperty("media_type") String mediaType,
 			@JsonProperty("data") String data,
-			@JsonProperty("url") String url) {
+			@JsonProperty("url") String url,
+			@JsonProperty("content") List<ContentBlock> content) {
 			// @formatter:on
 
 			/**
@@ -992,11 +1061,15 @@ public record Source(
 			 * @param data The content data.
 			 */
 			public Source(String mediaType, String data) {
-				this("base64", mediaType, data, null);
+				this("base64", mediaType, data, null, null);
 			}
 
 			public Source(String url) {
-				this("url", null, null, url);
+				this("url", null, null, url, null);
+			}
+
+			public Source(List<ContentBlock> content) {
+				this("content", null, null, null, content);
 			}
 
 		}
@@ -1029,6 +1102,12 @@ public static class ContentBlockBuilder {
 
 			private CacheControl cacheControl;
 
+			private String title;
+
+			private String context;
+
+			private Object citations;
+
 			public ContentBlockBuilder(ContentBlock contentBlock) {
 				this.type = contentBlock.type;
 				this.source = contentBlock.source;
@@ -1043,6 +1122,9 @@ public ContentBlockBuilder(ContentBlock contentBlock) {
 				this.thinking = contentBlock.thinking;
 				this.data = contentBlock.data;
 				this.cacheControl = contentBlock.cacheControl;
+				this.title = contentBlock.title;
+				this.context = contentBlock.context;
+				this.citations = contentBlock.citations;
 			}
 
 			public ContentBlockBuilder type(Type type) {
@@ -1112,7 +1194,8 @@ public ContentBlockBuilder cacheControl(CacheControl cacheControl) {
 
 			public ContentBlock build() {
 				return new ContentBlock(this.type, this.source, this.text, this.index, this.id, this.name, this.input,
-						this.toolUseId, this.content, this.signature, this.thinking, this.data, this.cacheControl);
+						this.toolUseId, this.content, this.signature, this.thinking, this.data, this.cacheControl,
+						this.title, this.context, this.citations);
 			}
 
 		}
diff --git a/models/spring-ai-anthropic/src/main/java/org/springframework/ai/anthropic/api/CitationDocument.java b/models/spring-ai-anthropic/src/main/java/org/springframework/ai/anthropic/api/CitationDocument.java
new file mode 100644
index 00000000000..c5da01b3a16
--- /dev/null
+++ b/models/spring-ai-anthropic/src/main/java/org/springframework/ai/anthropic/api/CitationDocument.java
@@ -0,0 +1,286 @@
+/*
+ * Copyright 2023-2025 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.ai.anthropic.api;
+
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Paths;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Base64;
+import java.util.List;
+import java.util.stream.Collectors;
+
+import org.springframework.ai.anthropic.AnthropicChatOptions;
+import org.springframework.ai.anthropic.Citation;
+import org.springframework.util.Assert;
+
+/**
+ * Builder class for creating citation-enabled documents. Provides a fluent API for
+ * constructing documents of different types that can be converted to ContentBlocks for
+ * the Anthropic API.
+ *
+ * <p>
+ * Citations allow Claude to reference specific parts of provided documents in its
+ * responses. When a citation document is included in a prompt, Claude can cite the source
+ * material, and citation metadata (character ranges, page numbers, or content blocks) is
+ * returned in the response.
+ *
+ * <h3>Usage Examples</h3>
+ *
+ * <p>
+ * <b>Plain Text Document:</b>
+ *
+ * <pre>{@code
+ * CitationDocument document = CitationDocument.builder()
+ *     .plainText("The Eiffel Tower was completed in 1889 in Paris, France.")
+ *     .title("Eiffel Tower Facts")
+ *     .build();
+ *
+ * AnthropicChatOptions options = AnthropicChatOptions.builder()
+ *     .model(AnthropicApi.ChatModel.CLAUDE_3_7_SONNET.getName())
+ *     .citationDocuments(document)
+ *     .build();
+ *
+ * ChatResponse response = chatModel.call(new Prompt("When was the Eiffel Tower built?", options));
+ *
+ * // Citations are available in response metadata
+ * List<Citation> citations = (List<Citation>) response.getMetadata().get("citations");
+ * }</pre>
+ *
+ * <p>
+ * <b>PDF Document:</b>
+ *
+ * <pre>{@code
+ * CitationDocument document = CitationDocument.builder()
+ *     .pdfFile("path/to/document.pdf")
+ *     .title("Technical Specification")
+ *     .build();
+ *
+ * // PDF citations include page numbers
+ * }</pre>
+ *
+ * <p>
+ * <b>Custom Content Blocks:</b>
+ *
+ * <pre>{@code
+ * CitationDocument document = CitationDocument.builder()
+ *     .customContent(
+ *         "Fact 1: The Great Wall spans 21,196 kilometers.",
+ *         "Fact 2: Construction began in the 7th century BC.",
+ *         "Fact 3: It was built to protect Chinese states."
+ *     )
+ *     .title("Great Wall Facts")
+ *     .build();
+ *
+ * // Custom content citations reference specific content blocks
+ * }</pre>
+ *
+ * @author Soby Chacko
+ * @since 1.1.0
+ * @see Citation
+ * @see AnthropicChatOptions#getCitationDocuments()
+ */
+public final class CitationDocument {
+
+	/**
+	 * Document types supported by Anthropic Citations API. Each type uses different
+	 * citation location formats in the response.
+	 */
+	public enum DocumentType {
+
+		/**
+		 * Plain text document with character-based citations. Text is automatically
+		 * chunked by sentences and citations return character start/end indices.
+		 */
+		PLAIN_TEXT,
+
+		/**
+		 * PDF document with page-based citations. Content is extracted and chunked from
+		 * the PDF, and citations return page start/end numbers.
+		 */
+		PDF,
+
+		/**
+		 * Custom content with user-defined blocks and block-based citations. Content is
+		 * provided as explicit blocks, and citations return block start/end indices.
+		 */
+		CUSTOM_CONTENT
+
+	}
+
+	private DocumentType type;
+
+	private String title;
+
+	private String context;
+
+	private Object sourceData; // String for text, byte[] for PDF, List<ContentBlock> for
+								// custom
+
+	private boolean citationsEnabled = false;
+
+	private CitationDocument() {
+	}
+
+	public static Builder builder() {
+		return new Builder();
+	}
+
+	/**
+	 * Convert this CitationDocument to a ContentBlock for API usage.
+	 * @return ContentBlock configured for citations
+	 */
+	public AnthropicApi.ContentBlock toContentBlock() {
+		AnthropicApi.ContentBlock.Source source = createSource();
+		return new AnthropicApi.ContentBlock(source, this.title, this.context, this.citationsEnabled, null);
+	}
+
+	private AnthropicApi.ContentBlock.Source createSource() {
+		return switch (this.type) {
+			case PLAIN_TEXT ->
+				new AnthropicApi.ContentBlock.Source("text", "text/plain", (String) this.sourceData, null, null);
+			case PDF -> {
+				String base64Data = Base64.getEncoder().encodeToString((byte[]) this.sourceData);
+				yield new AnthropicApi.ContentBlock.Source("base64", "application/pdf", base64Data, null, null);
+			}
+			case CUSTOM_CONTENT -> {
+				@SuppressWarnings("unchecked")
+				List<AnthropicApi.ContentBlock> content = (List<AnthropicApi.ContentBlock>) this.sourceData;
+				yield new AnthropicApi.ContentBlock.Source("content", null, null, null, content);
+			}
+		};
+	}
+
+	public boolean isCitationsEnabled() {
+		return this.citationsEnabled;
+	}
+
+	/**
+	 * Builder class for CitationDocument.
+	 */
+	public static class Builder {
+
+		private final CitationDocument document = new CitationDocument();
+
+		/**
+		 * Create a plain text document.
+		 * @param text The document text content
+		 * @return Builder for method chaining
+		 */
+		public Builder plainText(String text) {
+			Assert.hasText(text, "Text content cannot be null or empty");
+			this.document.type = DocumentType.PLAIN_TEXT;
+			this.document.sourceData = text;
+			return this;
+		}
+
+		/**
+		 * Create a PDF document from byte array.
+		 * @param pdfBytes The PDF file content as bytes
+		 * @return Builder for method chaining
+		 */
+		public Builder pdf(byte[] pdfBytes) {
+			Assert.notNull(pdfBytes, "PDF bytes cannot be null");
+			Assert.isTrue(pdfBytes.length > 0, "PDF bytes cannot be empty");
+			this.document.type = DocumentType.PDF;
+			this.document.sourceData = pdfBytes;
+			return this;
+		}
+
+		/**
+		 * Create a PDF document from file path.
+		 * @param filePath Path to the PDF file
+		 * @return Builder for method chaining
+		 * @throws IOException if file cannot be read
+		 */
+		public Builder pdfFile(String filePath) throws IOException {
+			Assert.hasText(filePath, "File path cannot be null or empty");
+			byte[] pdfBytes = Files.readAllBytes(Paths.get(filePath));
+			return pdf(pdfBytes);
+		}
+
+		/**
+		 * Create a custom content document with user-defined blocks.
+		 * @param contentBlocks List of content blocks for fine-grained citation control
+		 * @return Builder for method chaining
+		 */
+		public Builder customContent(List<AnthropicApi.ContentBlock> contentBlocks) {
+			Assert.notNull(contentBlocks, "Content blocks cannot be null");
+			Assert.notEmpty(contentBlocks, "Content blocks cannot be empty");
+			this.document.type = DocumentType.CUSTOM_CONTENT;
+			this.document.sourceData = new ArrayList<>(contentBlocks);
+			return this;
+		}
+
+		/**
+		 * Create a custom content document from text blocks.
+		 * @param textBlocks Variable number of text strings to create content blocks
+		 * @return Builder for method chaining
+		 */
+		public Builder customContent(String... textBlocks) {
+			Assert.notNull(textBlocks, "Text blocks cannot be null");
+			Assert.notEmpty(textBlocks, "Text blocks cannot be empty");
+			List<AnthropicApi.ContentBlock> blocks = Arrays.stream(textBlocks)
+				.map(AnthropicApi.ContentBlock::new)
+				.collect(Collectors.toList());
+			return customContent(blocks);
+		}
+
+		/**
+		 * Set the document title (optional, not included in citations).
+		 * @param title Document title for reference
+		 * @return Builder for method chaining
+		 */
+		public Builder title(String title) {
+			this.document.title = title;
+			return this;
+		}
+
+		/**
+		 * Set the document context (optional, not included in citations).
+		 * @param context Additional context or metadata about the document
+		 * @return Builder for method chaining
+		 */
+		public Builder context(String context) {
+			this.document.context = context;
+			return this;
+		}
+
+		/**
+		 * Enable or disable citations for this document.
+		 * @param enabled Whether citations should be enabled
+		 * @return Builder for method chaining
+		 */
+		public Builder citationsEnabled(boolean enabled) {
+			this.document.citationsEnabled = enabled;
+			return this;
+		}
+
+		/**
+		 * Build the CitationDocument.
+		 * @return Configured CitationDocument
+		 */
+		public CitationDocument build() {
+			Assert.notNull(this.document.type, "Document type must be specified");
+			Assert.notNull(this.document.sourceData, "Document source data must be specified");
+			return this.document;
+		}
+
+	}
+
+}
diff --git a/models/spring-ai-anthropic/src/main/java/org/springframework/ai/anthropic/api/StreamHelper.java b/models/spring-ai-anthropic/src/main/java/org/springframework/ai/anthropic/api/StreamHelper.java
index 2898a7b7aad..fbb26705450 100644
--- a/models/spring-ai-anthropic/src/main/java/org/springframework/ai/anthropic/api/StreamHelper.java
+++ b/models/spring-ai-anthropic/src/main/java/org/springframework/ai/anthropic/api/StreamHelper.java
@@ -164,7 +164,8 @@ else if (event.type().equals(EventType.CONTENT_BLOCK_START)) {
 			}
 			else if (contentBlockStartEvent.contentBlock() instanceof ContentBlockThinking thinkingBlock) {
 				ContentBlock cb = new ContentBlock(Type.THINKING, null, null, contentBlockStartEvent.index(), null,
-						null, null, null, null, thinkingBlock.signature(), thinkingBlock.thinking(), null, null);
+						null, null, null, null, thinkingBlock.signature(), thinkingBlock.thinking(), null, null, null,
+						null, null);
 				contentBlockReference.get().withType(event.type().name()).withContent(List.of(cb));
 			}
 			else {
@@ -181,12 +182,12 @@ else if (event.type().equals(EventType.CONTENT_BLOCK_DELTA)) {
 			}
 			else if (contentBlockDeltaEvent.delta() instanceof ContentBlockDeltaThinking thinking) {
 				ContentBlock cb = new ContentBlock(Type.THINKING_DELTA, null, null, contentBlockDeltaEvent.index(),
-						null, null, null, null, null, null, thinking.thinking(), null, null);
+						null, null, null, null, null, null, thinking.thinking(), null, null, null, null, null);
 				contentBlockReference.get().withType(event.type().name()).withContent(List.of(cb));
 			}
 			else if (contentBlockDeltaEvent.delta() instanceof ContentBlockDeltaSignature sig) {
 				ContentBlock cb = new ContentBlock(Type.SIGNATURE_DELTA, null, null, contentBlockDeltaEvent.index(),
-						null, null, null, null, null, sig.signature(), null, null, null);
+						null, null, null, null, null, sig.signature(), null, null, null, null, null, null);
 				contentBlockReference.get().withType(event.type().name()).withContent(List.of(cb));
 			}
 			else {
diff --git a/models/spring-ai-anthropic/src/test/java/org/springframework/ai/anthropic/AnthropicCitationIT.java b/models/spring-ai-anthropic/src/test/java/org/springframework/ai/anthropic/AnthropicCitationIT.java
new file mode 100644
index 00000000000..092455733ed
--- /dev/null
+++ b/models/spring-ai-anthropic/src/test/java/org/springframework/ai/anthropic/AnthropicCitationIT.java
@@ -0,0 +1,301 @@
+/*
+ * Copyright 2023-2025 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.ai.anthropic;
+
+import java.io.IOException;
+import java.util.List;
+
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.condition.EnabledIfEnvironmentVariable;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import org.springframework.ai.anthropic.api.AnthropicApi;
+import org.springframework.ai.anthropic.api.CitationDocument;
+import org.springframework.ai.chat.messages.UserMessage;
+import org.springframework.ai.chat.model.ChatResponse;
+import org.springframework.ai.chat.prompt.Prompt;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.SpringBootConfiguration;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.context.annotation.Bean;
+import org.springframework.util.StringUtils;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+/**
+ * Integration tests for Anthropic Citations API support.
+ *
+ * @author Soby Chacko
+ * @since 1.1.0
+ */
+@SpringBootTest(classes = AnthropicCitationIT.Config.class)
+@EnabledIfEnvironmentVariable(named = "ANTHROPIC_API_KEY", matches = ".+")
+class AnthropicCitationIT {
+
+	private static final Logger logger = LoggerFactory.getLogger(AnthropicCitationIT.class);
+
+	@Autowired
+	private AnthropicChatModel chatModel;
+
+	@Test
+	void testPlainTextCitation() {
+		// Create a citation document with plain text
+		CitationDocument document = CitationDocument.builder()
+			.plainText(
+					"The Eiffel Tower is located in Paris, France. It was completed in 1889 and stands 330 meters tall.")
+			.title("Eiffel Tower Facts")
+			.citationsEnabled(true)
+			.build();
+
+		// Create a prompt asking a question about the document
+		// Use explicit instruction to answer from the provided document
+		UserMessage userMessage = new UserMessage(
+				"Based solely on the provided document, where is the Eiffel Tower located and when was it completed?");
+
+		AnthropicChatOptions options = AnthropicChatOptions.builder()
+			.model(AnthropicApi.ChatModel.CLAUDE_3_7_SONNET.getName())
+			.maxTokens(2048)
+			.temperature(0.0) // Use temperature 0 for more deterministic responses
+			.citationDocuments(document)
+			.build();
+
+		Prompt prompt = new Prompt(List.of(userMessage), options);
+
+		// Call the model
+		ChatResponse response = this.chatModel.call(prompt);
+
+		// Verify response exists and is not empty
+		assertThat(response).isNotNull();
+		assertThat(response.getResults()).isNotEmpty();
+		String responseText = response.getResult().getOutput().getText();
+		assertThat(responseText).as("Response text should not be blank").isNotBlank();
+
+		// Verify citations are present in metadata (this is the core feature being
+		// tested)
+		Object citationsObj = response.getMetadata().get("citations");
+		assertThat(citationsObj).as("Citations should be present in response metadata").isNotNull();
+
+		@SuppressWarnings("unchecked")
+		List<Citation> citations = (List<Citation>) citationsObj;
+		assertThat(citations).as("Citation list should not be empty").isNotEmpty();
+
+		// Verify citation structure - all citations should have proper fields
+		for (Citation citation : citations) {
+			assertThat(citation.getType()).as("Citation type should be CHAR_LOCATION for plain text")
+				.isEqualTo(Citation.LocationType.CHAR_LOCATION);
+			assertThat(citation.getCitedText()).as("Cited text should not be blank").isNotBlank();
+			assertThat(citation.getDocumentIndex()).as("Document index should be 0 (first document)").isEqualTo(0);
+			assertThat(citation.getDocumentTitle()).as("Document title should match").isEqualTo("Eiffel Tower Facts");
+			assertThat(citation.getStartCharIndex()).as("Start char index should be non-negative")
+				.isGreaterThanOrEqualTo(0);
+			assertThat(citation.getEndCharIndex()).as("End char index should be greater than start")
+				.isGreaterThan(citation.getStartCharIndex());
+		}
+	}
+
+	@Test
+	void testMultipleCitationDocuments() {
+		// Create multiple citation documents
+		CitationDocument parisDoc = CitationDocument.builder()
+			.plainText("Paris is the capital city of France. It has a population of about 2.1 million people.")
+			.title("Paris Information")
+			.citationsEnabled(true)
+			.build();
+
+		CitationDocument eiffelDoc = CitationDocument.builder()
+			.plainText("The Eiffel Tower was designed by Gustave Eiffel and completed in 1889 for the World's Fair.")
+			.title("Eiffel Tower History")
+			.citationsEnabled(true)
+			.build();
+
+		// Use explicit instruction to answer from the provided documents
+		UserMessage userMessage = new UserMessage(
+				"Based solely on the provided documents, what is the capital of France and who designed the Eiffel Tower?");
+
+		AnthropicChatOptions options = AnthropicChatOptions.builder()
+			.model(AnthropicApi.ChatModel.CLAUDE_3_7_SONNET.getName())
+			.maxTokens(1024)
+			.temperature(0.0) // Use temperature 0 for more deterministic responses
+			.citationDocuments(parisDoc, eiffelDoc)
+			.build();
+
+		Prompt prompt = new Prompt(List.of(userMessage), options);
+
+		// Call the model
+		ChatResponse response = this.chatModel.call(prompt);
+
+		// Verify response exists and is not empty
+		assertThat(response).isNotNull();
+		assertThat(response.getResults()).isNotEmpty();
+		String responseText = response.getResult().getOutput().getText();
+		assertThat(responseText).as("Response text should not be blank").isNotBlank();
+
+		// Verify citations are present (this is the core feature being tested)
+		Object citationsObj = response.getMetadata().get("citations");
+		assertThat(citationsObj).as("Citations should be present in response metadata").isNotNull();
+
+		@SuppressWarnings("unchecked")
+		List<Citation> citations = (List<Citation>) citationsObj;
+		assertThat(citations).as("Citation list should not be empty").isNotEmpty();
+
+		// Verify we have citations from both documents
+		// Check that citations reference both document indices (0 and 1)
+		boolean hasDoc0 = citations.stream().anyMatch(c -> c.getDocumentIndex() == 0);
+		boolean hasDoc1 = citations.stream().anyMatch(c -> c.getDocumentIndex() == 1);
+		assertThat(hasDoc0 && hasDoc1).as("Should have citations from at least one document").isTrue();
+
+		// Verify citation structure for all citations
+		for (Citation citation : citations) {
+			assertThat(citation.getType()).as("Citation type should be CHAR_LOCATION for plain text")
+				.isEqualTo(Citation.LocationType.CHAR_LOCATION);
+			assertThat(citation.getCitedText()).as("Cited text should not be blank").isNotBlank();
+			assertThat(citation.getDocumentIndex()).as("Document index should be 0 or 1").isIn(0, 1);
+			assertThat(citation.getDocumentTitle()).as("Document title should be one of the provided titles")
+				.isIn("Paris Information", "Eiffel Tower History");
+			assertThat(citation.getStartCharIndex()).as("Start char index should be non-negative")
+				.isGreaterThanOrEqualTo(0);
+			assertThat(citation.getEndCharIndex()).as("End char index should be greater than start")
+				.isGreaterThan(citation.getStartCharIndex());
+		}
+	}
+
+	@Test
+	void testCustomContentCitation() {
+		// Create a citation document with custom content blocks for fine-grained citation
+		// control
+		CitationDocument document = CitationDocument.builder()
+			.customContent("The Great Wall of China is approximately 21,196 kilometers long.",
+					"It was built over many centuries, starting in the 7th century BC.",
+					"The wall was constructed to protect Chinese states from invasions.")
+			.title("Great Wall Facts")
+			.citationsEnabled(true)
+			.build();
+
+		UserMessage userMessage = new UserMessage(
+				"Based solely on the provided document, how long is the Great Wall of China and when was it started?");
+
+		AnthropicChatOptions options = AnthropicChatOptions.builder()
+			.model(AnthropicApi.ChatModel.CLAUDE_3_7_SONNET.getName())
+			.maxTokens(1024)
+			.temperature(0.0)
+			.citationDocuments(document)
+			.build();
+
+		Prompt prompt = new Prompt(List.of(userMessage), options);
+		ChatResponse response = this.chatModel.call(prompt);
+
+		// Verify response and citations
+		assertThat(response).isNotNull();
+		assertThat(response.getResults()).isNotEmpty();
+		assertThat(response.getResult().getOutput().getText()).isNotBlank();
+
+		Object citationsObj = response.getMetadata().get("citations");
+		assertThat(citationsObj).as("Citations should be present in response metadata").isNotNull();
+
+		@SuppressWarnings("unchecked")
+		List<Citation> citations = (List<Citation>) citationsObj;
+		assertThat(citations).as("Citation list should not be empty").isNotEmpty();
+
+		// For custom content, citations should use CONTENT_BLOCK_LOCATION type
+		for (Citation citation : citations) {
+			assertThat(citation.getType()).as("Citation type should be CONTENT_BLOCK_LOCATION for custom content")
+				.isEqualTo(Citation.LocationType.CONTENT_BLOCK_LOCATION);
+			assertThat(citation.getCitedText()).as("Cited text should not be blank").isNotBlank();
+			assertThat(citation.getDocumentIndex()).as("Document index should be 0").isEqualTo(0);
+			assertThat(citation.getDocumentTitle()).as("Document title should match").isEqualTo("Great Wall Facts");
+			// For content block citations, we have start/end block indices instead of
+			// char indices
+			assertThat(citation.getStartBlockIndex()).as("Start block index should be non-negative")
+				.isGreaterThanOrEqualTo(0);
+			assertThat(citation.getEndBlockIndex()).as("End block index should be >= start")
+				.isGreaterThanOrEqualTo(citation.getStartBlockIndex());
+		}
+	}
+
+	@Test
+	void testPdfCitation() throws IOException {
+		// Load the test PDF from resources
+		CitationDocument document = CitationDocument.builder()
+			.pdfFile("src/test/resources/spring-ai-reference-overview.pdf")
+			.title("Spring AI Reference")
+			.citationsEnabled(true)
+			.build();
+
+		UserMessage userMessage = new UserMessage("Based solely on the provided document, what is Spring AI?");
+
+		AnthropicChatOptions options = AnthropicChatOptions.builder()
+			.model(AnthropicApi.ChatModel.CLAUDE_3_7_SONNET.getName())
+			.maxTokens(1024)
+			.temperature(0.0)
+			.citationDocuments(document)
+			.build();
+
+		Prompt prompt = new Prompt(List.of(userMessage), options);
+		ChatResponse response = this.chatModel.call(prompt);
+
+		// Verify response and citations
+		assertThat(response).isNotNull();
+		assertThat(response.getResults()).isNotEmpty();
+		assertThat(response.getResult().getOutput().getText()).isNotBlank();
+
+		Object citationsObj = response.getMetadata().get("citations");
+		assertThat(citationsObj).as("Citations should be present for PDF documents").isNotNull();
+
+		@SuppressWarnings("unchecked")
+		List<Citation> citations = (List<Citation>) citationsObj;
+		assertThat(citations).as("Citation list should not be empty for PDF").isNotEmpty();
+
+		// For PDF documents, citations should use PAGE_LOCATION type
+		for (Citation citation : citations) {
+			assertThat(citation.getType()).as("Citation type should be PAGE_LOCATION for PDF")
+				.isEqualTo(Citation.LocationType.PAGE_LOCATION);
+			assertThat(citation.getCitedText()).as("Cited text should not be blank").isNotBlank();
+			assertThat(citation.getDocumentIndex()).as("Document index should be 0").isEqualTo(0);
+			assertThat(citation.getDocumentTitle()).as("Document title should match").isEqualTo("Spring AI Reference");
+			// For page citations, we have start/end page numbers instead of char indices
+			assertThat(citation.getStartPageNumber()).as("Start page number should be positive").isGreaterThan(0);
+			assertThat(citation.getEndPageNumber()).as("End page number should be >= start")
+				.isGreaterThanOrEqualTo(citation.getStartPageNumber());
+		}
+	}
+
+	@SpringBootConfiguration
+	public static class Config {
+
+		@Bean
+		public AnthropicApi anthropicApi() {
+			return AnthropicApi.builder().apiKey(getApiKey()).build();
+		}
+
+		private String getApiKey() {
+			String apiKey = System.getenv("ANTHROPIC_API_KEY");
+			if (!StringUtils.hasText(apiKey)) {
+				throw new IllegalArgumentException(
+						"You must provide an API key. Put it in an environment variable under the name ANTHROPIC_API_KEY");
+			}
+			return apiKey;
+		}
+
+		@Bean
+		public AnthropicChatModel anthropicChatModel(AnthropicApi api) {
+			return AnthropicChatModel.builder().anthropicApi(api).build();
+		}
+
+	}
+
+}
diff --git a/spring-ai-docs/src/main/antora/modules/ROOT/pages/api/chat/anthropic-chat.adoc b/spring-ai-docs/src/main/antora/modules/ROOT/pages/api/chat/anthropic-chat.adoc
index 55d48c91aa2..ce20b348cda 100644
--- a/spring-ai-docs/src/main/antora/modules/ROOT/pages/api/chat/anthropic-chat.adoc
+++ b/spring-ai-docs/src/main/antora/modules/ROOT/pages/api/chat/anthropic-chat.adoc
@@ -986,6 +986,398 @@ var userMessage = new UserMessage(
 var response = this.chatModel.call(new Prompt(List.of(userMessage)));
 ----
 
+== Citations
+
+Anthropic's https://docs.anthropic.com/en/docs/build-with-claude/citations[Citations API] allows Claude to reference specific parts of provided documents when generating responses.
+When citation documents are included in a prompt, Claude can cite the source material, and citation metadata (character ranges, page numbers, or content blocks) is returned in the response metadata.
+
+Citations help improve:
+
+* **Accuracy verification**: Users can verify Claude's responses against source material
+* **Transparency**: See exactly which parts of documents informed the response
+* **Compliance**: Meet requirements for source attribution in regulated industries
+* **Trust**: Build confidence by showing where information came from
+
+[NOTE]
+====
+*Supported Models*
+
+Citations are supported on Claude 3.7 Sonnet and Claude 4 models (Opus and Sonnet).
+
+*Document Types*
+
+Three types of citation documents are supported:
+
+* **Plain Text**: Text content with character-level citations
+* **PDF**: PDF documents with page-level citations
+* **Custom Content**: User-defined content blocks with block-level citations
+====
+
+=== Creating Citation Documents
+
+Use the `CitationDocument` builder to create documents that can be cited:
+
+==== Plain Text Documents
+
+[source,java]
+----
+CitationDocument document = CitationDocument.builder()
+    .plainText("The Eiffel Tower was completed in 1889 in Paris, France. " +
+               "It stands 330 meters tall and was designed by Gustave Eiffel.")
+    .title("Eiffel Tower Facts")
+    .citationsEnabled(true)
+    .build();
+----
+
+==== PDF Documents
+
+[source,java]
+----
+// From file path
+CitationDocument document = CitationDocument.builder()
+    .pdfFile("path/to/document.pdf")
+    .title("Technical Specification")
+    .citationsEnabled(true)
+    .build();
+
+// From byte array
+byte[] pdfBytes = loadPdfBytes();
+CitationDocument document = CitationDocument.builder()
+    .pdf(pdfBytes)
+    .title("Product Manual")
+    .citationsEnabled(true)
+    .build();
+----
+
+==== Custom Content Blocks
+
+For fine-grained citation control, use custom content blocks:
+
+[source,java]
+----
+CitationDocument document = CitationDocument.builder()
+    .customContent(
+        "The Great Wall of China is approximately 21,196 kilometers long.",
+        "It was built over many centuries, starting in the 7th century BC.",
+        "The wall was constructed to protect Chinese states from invasions."
+    )
+    .title("Great Wall Facts")
+    .citationsEnabled(true)
+    .build();
+----
+
+=== Using Citations in Requests
+
+Include citation documents in your chat options:
+
+[source,java]
+----
+ChatResponse response = chatModel.call(
+    new Prompt(
+        "When was the Eiffel Tower built and how tall is it?",
+        AnthropicChatOptions.builder()
+            .model("claude-3-7-sonnet-latest")
+            .maxTokens(1024)
+            .citationDocuments(document)
+            .build()
+    )
+);
+----
+
+==== Multiple Documents
+
+You can provide multiple documents for Claude to reference:
+
+[source,java]
+----
+CitationDocument parisDoc = CitationDocument.builder()
+    .plainText("Paris is the capital city of France with a population of 2.1 million.")
+    .title("Paris Information")
+    .citationsEnabled(true)
+    .build();
+
+CitationDocument eiffelDoc = CitationDocument.builder()
+    .plainText("The Eiffel Tower was designed by Gustave Eiffel for the 1889 World's Fair.")
+    .title("Eiffel Tower History")
+    .citationsEnabled(true)
+    .build();
+
+ChatResponse response = chatModel.call(
+    new Prompt(
+        "What is the capital of France and who designed the Eiffel Tower?",
+        AnthropicChatOptions.builder()
+            .model("claude-3-7-sonnet-latest")
+            .citationDocuments(parisDoc, eiffelDoc)
+            .build()
+    )
+);
+----
+
+=== Accessing Citations
+
+Citations are returned in the response metadata:
+
+[source,java]
+----
+ChatResponse response = chatModel.call(prompt);
+
+// Get citations from metadata
+@SuppressWarnings("unchecked")
+List<Citation> citations = (List<Citation>) response.getMetadata().get("citations");
+
+// Optional: Get citation count directly from metadata
+Integer citationCount = (Integer) response.getMetadata().get("citationCount");
+System.out.println("Total citations: " + citationCount);
+
+// Process each citation
+for (Citation citation : citations) {
+    System.out.println("Document: " + citation.getDocumentTitle());
+    System.out.println("Location: " + citation.getLocationDescription());
+    System.out.println("Cited text: " + citation.getCitedText());
+    System.out.println("Document index: " + citation.getDocumentIndex());
+    System.out.println();
+}
+----
+
+=== Citation Types
+
+Citations contain different location information depending on the document type:
+
+==== Character Location (Plain Text)
+
+For plain text documents, citations include character indices:
+
+[source,java]
+----
+Citation citation = citations.get(0);
+if (citation.getType() == Citation.LocationType.CHAR_LOCATION) {
+    int start = citation.getStartCharIndex();
+    int end = citation.getEndCharIndex();
+    String text = citation.getCitedText();
+    System.out.println("Characters " + start + "-" + end + ": " + text);
+}
+----
+
+==== Page Location (PDF)
+
+For PDF documents, citations include page numbers:
+
+[source,java]
+----
+Citation citation = citations.get(0);
+if (citation.getType() == Citation.LocationType.PAGE_LOCATION) {
+    int startPage = citation.getStartPageNumber();
+    int endPage = citation.getEndPageNumber();
+    System.out.println("Pages " + startPage + "-" + endPage);
+}
+----
+
+==== Content Block Location (Custom Content)
+
+For custom content, citations reference specific content blocks:
+
+[source,java]
+----
+Citation citation = citations.get(0);
+if (citation.getType() == Citation.LocationType.CONTENT_BLOCK_LOCATION) {
+    int startBlock = citation.getStartBlockIndex();
+    int endBlock = citation.getEndBlockIndex();
+    System.out.println("Content blocks " + startBlock + "-" + endBlock);
+}
+----
+
+=== Complete Example
+
+Here's a complete example demonstrating citation usage:
+
+[source,java]
+----
+// Create a citation document
+CitationDocument document = CitationDocument.builder()
+    .plainText("Spring AI is an application framework for AI engineering. " +
+               "It provides a Spring-friendly API for developing AI applications. " +
+               "The framework includes abstractions for chat models, embedding models, " +
+               "and vector databases.")
+    .title("Spring AI Overview")
+    .citationsEnabled(true)
+    .build();
+
+// Call the model with the document
+ChatResponse response = chatModel.call(
+    new Prompt(
+        "What is Spring AI?",
+        AnthropicChatOptions.builder()
+            .model("claude-3-7-sonnet-latest")
+            .maxTokens(1024)
+            .citationDocuments(document)
+            .build()
+    )
+);
+
+// Display the response
+System.out.println("Response: " + response.getResult().getOutput().getText());
+System.out.println("\nCitations:");
+
+// Process citations
+List<Citation> citations = (List<Citation>) response.getMetadata().get("citations");
+
+if (citations != null && !citations.isEmpty()) {
+    for (int i = 0; i < citations.size(); i++) {
+        Citation citation = citations.get(i);
+        System.out.println("\n[" + (i + 1) + "] " + citation.getDocumentTitle());
+        System.out.println("    Location: " + citation.getLocationDescription());
+        System.out.println("    Text: " + citation.getCitedText());
+    }
+} else {
+    System.out.println("No citations were provided in the response.");
+}
+----
+
+=== Best Practices
+
+1. **Use descriptive titles**: Provide meaningful titles for citation documents to help users identify sources in the citations.
+2. **Check for null citations**: Not all responses will include citations, so always validate the citations metadata exists before accessing it.
+3. **Consider document size**: Larger documents provide more context but consume more input tokens and may affect response time.
+4. **Leverage multiple documents**: When answering questions that span multiple sources, provide all relevant documents in a single request rather than making multiple calls.
+5. **Use appropriate document types**: Choose plain text for simple content, PDF for existing documents, and custom content blocks when you need fine-grained control over citation granularity.
+
+=== Real-World Use Cases
+
+==== Legal Document Analysis
+
+Analyze contracts and legal documents while maintaining source attribution:
+
+[source,java]
+----
+CitationDocument contract = CitationDocument.builder()
+    .pdfFile("merger-agreement.pdf")
+    .title("Merger Agreement 2024")
+    .citationsEnabled(true)
+    .build();
+
+ChatResponse response = chatModel.call(
+    new Prompt(
+        "What are the key termination clauses in this contract?",
+        AnthropicChatOptions.builder()
+            .model("claude-sonnet-4")
+            .maxTokens(2000)
+            .citationDocuments(contract)
+            .build()
+    )
+);
+
+// Citations will reference specific pages in the PDF
+----
+
+==== Customer Support Knowledge Base
+
+Provide accurate customer support answers with verifiable sources:
+
+[source,java]
+----
+CitationDocument kbArticle1 = CitationDocument.builder()
+    .plainText(loadKnowledgeBaseArticle("authentication"))
+    .title("Authentication Guide")
+    .citationsEnabled(true)
+    .build();
+
+CitationDocument kbArticle2 = CitationDocument.builder()
+    .plainText(loadKnowledgeBaseArticle("billing"))
+    .title("Billing FAQ")
+    .citationsEnabled(true)
+    .build();
+
+ChatResponse response = chatModel.call(
+    new Prompt(
+        "How do I reset my password and update my billing information?",
+        AnthropicChatOptions.builder()
+            .model("claude-3-7-sonnet-latest")
+            .citationDocuments(kbArticle1, kbArticle2)
+            .build()
+    )
+);
+
+// Citations show which KB articles were referenced
+----
+
+==== Research and Compliance
+
+Generate reports that require source citations for compliance:
+
+[source,java]
+----
+CitationDocument clinicalStudy = CitationDocument.builder()
+    .pdfFile("clinical-trial-results.pdf")
+    .title("Clinical Trial Phase III Results")
+    .citationsEnabled(true)
+    .build();
+
+CitationDocument regulatoryGuidance = CitationDocument.builder()
+    .plainText(loadRegulatoryDocument())
+    .title("FDA Guidance Document")
+    .citationsEnabled(true)
+    .build();
+
+ChatResponse response = chatModel.call(
+    new Prompt(
+        "Summarize the efficacy findings and regulatory implications.",
+        AnthropicChatOptions.builder()
+            .model("claude-sonnet-4")
+            .maxTokens(3000)
+            .citationDocuments(clinicalStudy, regulatoryGuidance)
+            .build()
+    )
+);
+
+// Citations provide audit trail for compliance
+----
+
+=== Citation Document Options
+
+==== Context Field
+
+Optionally provide context about the document that won't be cited but can guide Claude's understanding:
+
+[source,java]
+----
+CitationDocument document = CitationDocument.builder()
+    .plainText("...")
+    .title("Legal Contract")
+    .context("This is a merger agreement dated January 2024 between Company A and Company B")
+    .build();
+----
+
+==== Controlling Citations
+
+By default, citations are disabled for all documents (opt-in behavior).
+To enable citations, explicitly set `citationsEnabled(true)`:
+
+[source,java]
+----
+CitationDocument document = CitationDocument.builder()
+    .plainText("The Eiffel Tower was completed in 1889...")
+    .title("Historical Facts")
+    .citationsEnabled(true)  // Explicitly enable citations for this document
+    .build();
+----
+
+You can also provide documents without citations for background context:
+
+[source,java]
+----
+CitationDocument backgroundDoc = CitationDocument.builder()
+    .plainText("Background information about the industry...")
+    .title("Context Document")
+    // citationsEnabled defaults to false - Claude will use this but not cite it
+    .build();
+----
+
+[NOTE]
+====
+Anthropic requires consistent citation settings across all documents in a request.
+You cannot mix citation-enabled and citation-disabled documents in the same request.
+====
+
 == Sample Controller
 
 https://start.spring.io/[Create] a new Spring Boot project and add the `spring-ai-starter-model-anthropic` to your pom (or gradle) dependencies.