fix(DIS-154): parse [ATTACH:] markers before sanitization

sanitizeForDiscord() replaced workspace paths with <disclaw> before
parseAttachments() could read them, making all resolved paths invalid.

Fix: extract attach paths from raw result.text first, then sanitize
the marker-free text. sendResponse() accepts pre-resolved paths to
skip redundant re-parsing.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/discord/send-response.ts

@@ -67,24 +67,30 @@ export function validateAttachPath(filePath: string, workspacePath: string): str
 
 /**
  * Sends an agent response to a Discord channel.
- * - Parses [ATTACH: path] markers and sends valid files as attachments.
- * - Text > 4000 chars (after stripping markers) is sent as a Markdown file attachment.
+ * - If preResolvedAttachPaths is given, those files are sent as attachments (markers
+ *   must already be stripped from `text`). Otherwise [ATTACH: path] markers are parsed
+ *   from `text` on the fly (requires workspacePath).
+ * - Text > 4000 chars is sent as a Markdown file attachment.
  * - Text <= 4000 chars is split with splitForDiscord and sent as plain messages.
  */
 export async function sendResponse(
   channel: TextChannel,
   text: string,
   _triggerMessage: Message,
-  workspacePath?: string
+  workspacePath?: string,
+  preResolvedAttachPaths?: string[]
 ): Promise<void> {
-  if (text.length === 0) {
+  if (text.length === 0 && (!preResolvedAttachPaths || preResolvedAttachPaths.length === 0)) {
     return;
   }
 
-  // Parse [ATTACH: ...] markers if we have a workspace context
+  // Use pre-resolved paths (already extracted before sanitization) when available,
+  // otherwise fall back to parsing markers from the text (requires workspacePath).
   let cleanText = text;
   let attachPaths: string[] = [];
-  if (workspacePath) {
+  if (preResolvedAttachPaths) {
+    attachPaths = preResolvedAttachPaths;
+  } else if (workspacePath) {
     const parsed = parseAttachments(text, workspacePath);
     cleanText = parsed.text;
     attachPaths = parsed.attachPaths;

src/router.ts

@@ -5,7 +5,7 @@ import { DisclawConfig } from "./config/loader";
 import { runAgent } from "./agent/runner";
 import { sanitizeForDiscord } from "./runtime/sanitize";
 import { ChannelQueue } from "./runtime/channel-queue";
-import { sendResponse } from "./discord/send-response";
+import { sendResponse, parseAttachments } from "./discord/send-response";
 import { processAttachments } from "./discord/attachment-inbox";
 import type { RunResult } from "./agent/types";
 
@@ -90,7 +90,13 @@ export async function routeMessage(
           message.author.username
         );
 
-        const sanitizedResponse = sanitizeForDiscord(result.text, sanitizeOpts);
+        // Extract [ATTACH: ...] markers BEFORE sanitization so that workspace
+        // paths inside the markers are still resolvable.
+        const { text: textWithoutMarkers, attachPaths } = parseAttachments(
+          result.text,
+          workspace.workspace_path
+        );
+        const sanitizedResponse = sanitizeForDiscord(textWithoutMarkers, sanitizeOpts);
 
         let firstMsgId: string | null = null;
 
@@ -108,7 +114,8 @@ export async function routeMessage(
         // Temporarily patch channel.send for sendResponse
         (channel as unknown as { send: typeof patchedSend }).send = patchedSend;
         try {
-          await sendResponse(channel, sanitizedResponse, message, workspace.workspace_path);
+          // Pass pre-parsed attachPaths; sendResponse skips re-parsing when provided
+          await sendResponse(channel, sanitizedResponse, message, workspace.workspace_path, attachPaths);
         } finally {
           (channel as unknown as { send: typeof originalSend }).send = originalSend;
         }