fix(session): always post session info as persistent message

src/slack/handler.ts

@@ -67,6 +67,37 @@ export function resolveSessionId(
 
 export const SESSION_ID_RE = /(?::link:\s*`|Session:\s*)([0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12})/;
 
+export function extractSessionIdFromMessage(m: any): string | null {
+  // 1. Try text field first
+  const text = (m.text || "").replace(/<@[A-Z0-9]+>/g, "").trim();
+  const textMatch = text.match(SESSION_ID_RE);
+  if (textMatch) return textMatch[1] ?? null;
+
+  // 2. Try blocks (markdown blocks from Assistant API may not populate text)
+  if (Array.isArray(m.blocks)) {
+    for (const block of m.blocks) {
+      // Direct text/content fields (markdown blocks)
+      const blockText = block.text ?? block.content ?? "";
+      const blockMatch = blockText.match(SESSION_ID_RE);
+      if (blockMatch) return blockMatch[1] ?? null;
+
+      // rich_text blocks: Slack may convert markdown blocks to rich_text in conversations.replies
+      if (block.type === "rich_text" && Array.isArray(block.elements)) {
+        for (const section of block.elements) {
+          if (!Array.isArray(section.elements)) continue;
+          const sectionText = section.elements
+            .map((elem: any) => (elem.type === "emoji" ? `:${elem.name}:` : (elem.text ?? "")))
+            .join("");
+          const sectionMatch = sectionText.match(SESSION_ID_RE);
+          if (sectionMatch) return sectionMatch[1] ?? null;
+        }
+      }
+    }
+  }
+
+  return null;
+}
+
 async function fetchThreadContext(
   client: any,
   channel: string,
@@ -92,11 +123,11 @@ async function fetchThreadContext(
         const role = isBot ? "assistant" : "user";
         const text = (m.text || "").replace(/<@[A-Z0-9]+>/g, "").trim();
 
-        // Extract session ID from bot messages
+        // Extract session ID from bot messages (check text + blocks)
         if (isBot) {
-          const sessionMatch = text.match(SESSION_ID_RE);
-          if (sessionMatch) {
-            lastSessionId = sessionMatch[1];
+          const sessionId = extractSessionIdFromMessage(m);
+          if (sessionId) {
+            lastSessionId = sessionId;
           }
         }
 
@@ -105,7 +136,7 @@ async function fetchThreadContext(
 
     if (messages.length === 0) return { context: "", lastSessionId };
 
-    console.log(`[thread] Loaded ${messages.length} prior message(s) from thread`);
+    console.log(`[thread] Loaded ${messages.length} prior message(s) from thread, lastSessionId: ${lastSessionId}`);
     const context = `Below is the prior conversation in this Slack thread for context:\n\n${messages.join("\n")}\n\n---\n`;
     return { context, lastSessionId };
   } catch (err: any) {
@@ -194,9 +225,9 @@ export function createMentionHandler(config: CCSlackConfig, queue: TaskQueue, ca
           .catch(() => {}),
       ]);
 
-      // Cancelled: send error + session info as ephemeral only
+      // Cancelled: send cancellation notice as ephemeral, session info as persistent
       if (isCancelled) {
-        const ephemeralParts: Promise<void>[] = [
+        const parts: Promise<void>[] = [
           client.chat.postEphemeral({
             channel: event.channel,
             user: event.user,
@@ -206,16 +237,15 @@ export function createMentionHandler(config: CCSlackConfig, queue: TaskQueue, ca
         ];
         if (sessionId) {
           const sessionMsg = formatSessionInfo(sessionId, resolved.repoPath, config.claudePath);
-          ephemeralParts.push(
-            client.chat.postEphemeral({
+          parts.push(
+            client.chat.postMessage({
               channel: event.channel,
-              user: event.user,
               thread_ts: event.ts,
               ...sessionMsg,
             }),
           );
         }
-        await Promise.all(ephemeralParts);
+        await Promise.all(parts);
       } else {
         // noreply: skip thread reply, send session info only to requester via ephemeral
         if (!noreply) {
@@ -225,14 +255,14 @@ export function createMentionHandler(config: CCSlackConfig, queue: TaskQueue, ca
           }
         }
 
-        // Post session info
+        // Post session info (always persistent for session continuity)
         if (sessionId) {
           const sessionMsg = formatSessionInfo(sessionId, resolved.repoPath, config.claudePath);
-          await postReplyOrEphemeral(
-            client,
-            { channel: event.channel, threadTs: noreply ? event.thread_ts : event.ts, user: event.user, noreply },
-            sessionMsg,
-          );
+          await client.chat.postMessage({
+            channel: event.channel,
+            thread_ts: event.thread_ts ?? event.ts,
+            ...sessionMsg,
+          });
         }
       }
 
@@ -343,7 +373,6 @@ export function createAssistant(config: CCSlackConfig, queue: TaskQueue, cancelM
       const startTime = Date.now();
       console.log(`[claude] Starting stream: claude -p "${prompt.slice(0, 50)}..." in ${resolved.repoPath}`);
 
-      let cancelled = false;
       try {
         await queue.enqueue(async () => {
           const streamer = client.chatStream({
@@ -387,9 +416,7 @@ export function createAssistant(config: CCSlackConfig, queue: TaskQueue, cancelM
                 console.log(`[thinking] ${preview}`);
               } else if (evt.type === "error") {
                 console.log(`[claude] Error: ${evt.error}`);
-                if (evt.error === "cancelled") {
-                  cancelled = true;
-                } else {
+                if (evt.error !== "cancelled") {
                   await streamer.append({ markdown_text: `\n\nError: ${evt.error}` });
                 }
               } else if (evt.type === "result") {
@@ -404,19 +431,10 @@ export function createAssistant(config: CCSlackConfig, queue: TaskQueue, cancelM
           }
         });
 
-        // Post session info: ephemeral if cancelled, public otherwise
+        // Post session info (always persistent for session continuity)
         if (sessionId) {
           const sessionMsg = formatSessionInfo(sessionId, resolved.repoPath, config.claudePath);
-          if (cancelled) {
-            await client.chat.postEphemeral({
-              channel: ev.channel,
-              user: ev.user,
-              thread_ts: ev.thread_ts || ev.ts,
-              ...sessionMsg,
-            });
-          } else {
-            await say(sessionMsg);
-          }
+          await say(sessionMsg);
         }
       } catch (err: any) {
         console.log(`[claude] Unhandled error: ${err.message}`);

tests/slack/handler.test.ts

@@ -1,6 +1,12 @@
 import { describe, expect, it, mock } from "bun:test";
 import type { CCSlackConfig } from "../../src/config";
-import { createReactionCancelHandler, resolveRepoPath, resolveSessionId, SESSION_ID_RE } from "../../src/slack/handler";
+import {
+  createReactionCancelHandler,
+  extractSessionIdFromMessage,
+  resolveRepoPath,
+  resolveSessionId,
+  SESSION_ID_RE,
+} from "../../src/slack/handler";
 import { formatSessionInfo } from "../../src/slack/responder";
 
 const mockConfig: CCSlackConfig = {
@@ -133,6 +139,108 @@ describe("SESSION_ID_RE", () => {
   });
 });
 
+describe("extractSessionIdFromMessage", () => {
+  const testUuid = "a1b2c3d4-e5f6-7890-abcd-ef1234567890";
+
+  it("extracts session ID from text field (Session: format)", () => {
+    const msg = { text: `Session: ${testUuid}`, bot_id: "B123" };
+    expect(extractSessionIdFromMessage(msg)).toBe(testUuid);
+  });
+
+  it("extracts session ID from text field (:link: format)", () => {
+    const msg = { text: `:link: \`${testUuid}\``, bot_id: "B123" };
+    expect(extractSessionIdFromMessage(msg)).toBe(testUuid);
+  });
+
+  it("extracts session ID from blocks when text is empty", () => {
+    const msg = {
+      text: "",
+      bot_id: "B123",
+      blocks: [
+        {
+          type: "markdown",
+          text: `---\n:link: \`${testUuid}\`\n\`\`\`\ncd /repo && claude --resume ${testUuid}\n\`\`\``,
+        },
+      ],
+    };
+    expect(extractSessionIdFromMessage(msg)).toBe(testUuid);
+  });
+
+  it("extracts session ID from blocks when text has no session info", () => {
+    const msg = {
+      text: "Some other text without session info",
+      bot_id: "B123",
+      blocks: [
+        { type: "markdown", text: "Here is my response..." },
+        { type: "markdown", text: `---\n:link: \`${testUuid}\`` },
+      ],
+    };
+    expect(extractSessionIdFromMessage(msg)).toBe(testUuid);
+  });
+
+  it("returns null when no session ID found anywhere", () => {
+    const msg = { text: "Just a regular message", bot_id: "B123", blocks: [] };
+    expect(extractSessionIdFromMessage(msg)).toBeNull();
+  });
+
+  it("returns null when message has no text and no blocks", () => {
+    const msg = { bot_id: "B123" };
+    expect(extractSessionIdFromMessage(msg)).toBeNull();
+  });
+
+  it("prefers text field over blocks", () => {
+    const textUuid = "11111111-2222-3333-4444-555555555555";
+    const blockUuid = "aaaaaaaa-bbbb-cccc-dddd-eeeeeeeeeeee";
+    const msg = {
+      text: `Session: ${textUuid}`,
+      bot_id: "B123",
+      blocks: [{ type: "markdown", text: `:link: \`${blockUuid}\`` }],
+    };
+    expect(extractSessionIdFromMessage(msg)).toBe(textUuid);
+  });
+
+  it("extracts session ID from rich_text blocks (Slack conversion of markdown blocks)", () => {
+    const msg = {
+      text: "",
+      bot_id: "B123",
+      blocks: [
+        {
+          type: "rich_text",
+          elements: [
+            {
+              type: "rich_text_section",
+              elements: [
+                { type: "emoji", name: "link" },
+                { type: "text", text: ` \`${testUuid}\`` },
+              ],
+            },
+          ],
+        },
+      ],
+    };
+    expect(extractSessionIdFromMessage(msg)).toBe(testUuid);
+  });
+
+  it("extracts session ID from rich_text with Session: prefix", () => {
+    const msg = {
+      text: "",
+      bot_id: "B123",
+      blocks: [
+        {
+          type: "rich_text",
+          elements: [
+            {
+              type: "rich_text_section",
+              elements: [{ type: "text", text: `Session: ${testUuid}` }],
+            },
+          ],
+        },
+      ],
+    };
+    expect(extractSessionIdFromMessage(msg)).toBe(testUuid);
+  });
+});
+
 describe("createReactionCancelHandler", () => {
   const config = mockConfig;