fix(web): preserve source revisions in chat citation links

CHANGELOG.md

@@ -19,6 +19,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Upgraded `hono` to `^4.12.18` to address CVE-2026-44455, CVE-2026-44456, CVE-2026-44457, CVE-2026-44458. [#1186](https://github.com/sourcebot-dev/sourcebot/pull/1186)
 - Upgraded `ip-address` to `^10.2.0` to address CVE-2026-42338. [#1189](https://github.com/sourcebot-dev/sourcebot/pull/1189)
 - Upgraded `fast-xml-builder` to `^1.2.0` to address CVE-2026-44664, CVE-2026-44665. [#1184](https://github.com/sourcebot-dev/sourcebot/pull/1184)
+- Fixed file citations from the `get_diff` tool not being reliably citable in chat answers. [#1205](https://github.com/sourcebot-dev/sourcebot/pull/1205)
 
 ### Changed
 - Reduced the log verbosity of the worker by changing various log messages from info to debug. [#1179](https://github.com/sourcebot-dev/sourcebot/pull/1179)

packages/web/src/features/chat/components/chatThread/answerCard.tsx

@@ -18,12 +18,14 @@ import useCaptureEvent from "@/hooks/useCaptureEvent";
 import { LangfuseWeb } from "langfuse";
 import { env } from "@sourcebot/shared/client";
 import isEqual from "fast-deep-equal/react";
+import { FileSource } from "../../types";
 
 interface AnswerCardProps {
     answerText: string;
     messageId: string;
     chatId: string;
     traceId?: string;
+    sources: FileSource[];
 }
 
 const langfuseWeb = env.NEXT_PUBLIC_LANGFUSE_PUBLIC_KEY ? new LangfuseWeb({
@@ -36,6 +38,7 @@ const AnswerCardComponent = forwardRef<HTMLDivElement, AnswerCardProps>(({
     messageId,
     chatId,
     traceId,
+    sources,
 }, forwardedRef) => {
     const markdownRendererRef = useRef<HTMLDivElement>(null);
     // eslint-disable-next-line react-hooks/refs -- ref.current is passed to a custom hook, not used directly in render output
@@ -53,14 +56,14 @@ const AnswerCardComponent = forwardRef<HTMLDivElement, AnswerCardProps>(({
 
     const onCopyAnswer = useCallback(() => {
         const baseUrl = typeof window !== 'undefined' ? window.location.origin : '';
-        const markdownText = convertLLMOutputToPortableMarkdown(answerText, baseUrl);
+        const markdownText = convertLLMOutputToPortableMarkdown(answerText, baseUrl, sources);
         navigator.clipboard.writeText(markdownText);
         toast({
             description: "✅ Copied to clipboard",
         });
         captureEvent('wa_chat_copy_answer_pressed', { chatId });
         return true;
-    }, [answerText, chatId, captureEvent, toast]);
+    }, [answerText, sources, chatId, captureEvent, toast]);
 
     const onFeedback = useCallback(async (feedbackType: 'like' | 'dislike') => {
         setIsSubmittingFeedback(true);

packages/web/src/features/chat/components/chatThread/chatThreadListItem.tsx

@@ -371,6 +371,7 @@ const ChatThreadListItemComponent = forwardRef<HTMLDivElement, ChatThreadListIte
                                 chatId={chatId}
                                 messageId={assistantMessage.id}
                                 traceId={assistantMessage.metadata?.traceId}
+                                sources={referencedFileSources}
                             />
                         ) : !isStreaming && (
                             <p className="text-destructive">Error: No answer response was provided</p>

packages/web/src/features/chat/utils.ts

@@ -244,13 +244,23 @@ export const createFileReference = ({ repo, path, startLine, endLine }: { repo:
  * Markdown format. Practically, this means converting references into Markdown
  * links and removing the answer tag.
  */
-export const convertLLMOutputToPortableMarkdown = (text: string, baseUrl: string): string => {
+export const convertLLMOutputToPortableMarkdown = (text: string, baseUrl: string, sources: FileSource[]): string => {
     return text
         .replace(ANSWER_TAG, '')
         .replace(FILE_REFERENCE_REGEX, (_, repo, fileName, startLine, endLine) => {
-            const displayName = fileName.split('/').pop() || fileName;
+            const reference = createFileReference({
+                repo,
+                path: fileName,
+                startLine,
+                endLine
+            });
+
+            const source = tryResolveFileReference(reference, sources);
+            if (!source) {
+                return fileName;
+            }
 
-            let linkText = displayName;
+            let linkText = source.name;
             if (startLine) {
                 if (endLine && startLine !== endLine) {
                     linkText += `:${startLine}-${endLine}`;
@@ -268,6 +278,7 @@ export const convertLLMOutputToPortableMarkdown = (text: string, baseUrl: string
             // Construct full browse URL
             const browsePath = getBrowsePath({
                 repoName: repo,
+                revisionName: source.revision,
                 path: fileName,
                 pathType: 'blob',
                 highlightRange,

packages/web/src/features/mcp/askCodebase.ts

@@ -196,8 +196,15 @@ export const askCodebase = (params: AskCodebaseParams): Promise<AskCodebaseResul
                 : undefined;
             const answerText = answerPart?.text ?? '';
 
+            const fileSources = finalMessages.flatMap((message) =>
+                message.parts
+                    .filter((part) => part.type === 'data-source')
+                    .map((part) => part.data)
+                    .filter((source) => source.type === 'file')
+            );
+
             const baseUrl = env.AUTH_URL;
-            const portableAnswer = convertLLMOutputToPortableMarkdown(answerText, baseUrl);
+            const portableAnswer = convertLLMOutputToPortableMarkdown(answerText, baseUrl, fileSources);
             const chatUrl = `${baseUrl}/chat/${chat.id}`;
 
             logger.debug(`Completed blocking agent for chat ${chat.id}`, { chatId: chat.id });

packages/web/src/features/tools/getDiff.ts

@@ -4,7 +4,7 @@ import { isServiceError } from '@/lib/utils';
 import description from './getDiff.txt';
 import { formatDiffAsGitDiff } from './utils';
 import { logger } from './logger';
-import { ToolDefinition } from './types';
+import { Source, ToolDefinition } from './types';
 import { CodeHostType } from '@sourcebot/db';
 import { getRepoInfoByName } from '@/actions';
 
@@ -49,6 +49,48 @@ export const getDiffDefinition: ToolDefinition<'get_diff', typeof getDiffRequest
 
         const gitDiffOutput = formatDiffAsGitDiff(response);
 
+        const sources: Source[] = response.files.flatMap((file) => {
+            // Deleted: only the base side exists.
+            if (file.newPath === null) {
+                return file.oldPath ? [{
+                    type: 'file' as const,
+                    repo: repoInfo.name,
+                    path: file.oldPath,
+                    name: file.oldPath.split('/').pop() ?? file.oldPath,
+                    revision: base,
+                }] : [];
+            }
+
+            // Renamed: emit both sides since they have distinct paths.
+            if (file.oldPath && file.oldPath !== file.newPath) {
+                return [
+                    {
+                        type: 'file' as const,
+                        repo: repoInfo.name,
+                        path: file.oldPath,
+                        name: file.oldPath.split('/').pop() ?? file.oldPath,
+                        revision: base,
+                    },
+                    {
+                        type: 'file' as const,
+                        repo: repoInfo.name,
+                        path: file.newPath,
+                        name: file.newPath.split('/').pop() ?? file.newPath,
+                        revision: head,
+                    },
+                ];
+            }
+
+            // Added or modified: only the head side is citable.
+            return [{
+                type: 'file' as const,
+                repo: repoInfo.name,
+                path: file.newPath,
+                name: file.newPath.split('/').pop() ?? file.newPath,
+                revision: head,
+            }];
+        });
+
         return {
             output: gitDiffOutput,
             metadata: {
@@ -58,6 +100,7 @@ export const getDiffDefinition: ToolDefinition<'get_diff', typeof getDiffRequest
                 base,
                 head,
             },
+            sources,
         };
     },
 };