Auto-reply: ack think directives

CHANGELOG.md

@@ -4,6 +4,7 @@
 
 ### Highlights
 - **Thinking directives & state:** `/t|/think|/thinking <level>` (aliases off|minimal|low|medium|high|max/highest). Inline applies to that message; directive-only message pins the level for the session; `/think:off` clears. Resolution: inline > session override > `inbound.reply.thinkingDefault` > off. Pi/Tau get `--thinking <level>` (except off); other agents append cue words (`think` → `think hard` → `think harder` → `ultrathink`). Heartbeat probe uses `HEARTBEAT /think:high`.
+- **Directive confirmations:** Directive-only messages now reply with an acknowledgement (`Thinking level set to high.` / `Thinking disabled.`) and reject unknown levels with a helpful hint (state is unchanged).
 - **Pi/Tau stability:** RPC replies buffered until the assistant turn finishes; parsers return consistent `texts[]`; web auto-replies keep a warm Tau RPC process to avoid cold starts.
 - **Claude prompt flow:** One-time `sessionIntro` with per-message `/think:high` bodyPrefix; system prompt always sent on first turn even with `sendSystemOnce`.
 - **Heartbeat UX:** Backpressure skips reply heartbeats while other commands run; skips don’t refresh session `updatedAt`; web/Twilio heartbeats normalize array payloads and optional `heartbeatCommand`.

docs/thinking.md

@@ -18,6 +18,7 @@
 ## Setting a session default
 - Send a message that is **only** the directive (whitespace allowed), e.g. `/think:medium` or `/t high`.
 - That sticks for the current session (per-sender by default); cleared by `/think:off` or session idle reset.
+- Confirmation reply is sent (`Thinking level set to high.` / `Thinking disabled.`). If the level is invalid (e.g. `/thinking big`), the command is rejected with a hint and the session state is left unchanged.
 
 ## Application by agent
 - **Pi/Tau**: injects `--thinking <level>` (skipped for `off`).

src/auto-reply/reply.ts

@@ -53,8 +53,10 @@ function normalizeThinkLevel(raw?: string | null): ThinkLevel | undefined {
 function extractThinkDirective(body?: string): {
 	cleaned: string;
 	thinkLevel?: ThinkLevel;
+	rawLevel?: string;
+	hasDirective: boolean;
 } {
-	if (!body) return { cleaned: "" };
+	if (!body) return { cleaned: "", hasDirective: false };
 	// Match the longest keyword first to avoid partial captures (e.g. "/think:high")
 	const match = body.match(
 		/\/(?:thinking|think|t)\s*:?\s*([a-zA-Z-]+)\b/i,
@@ -63,7 +65,12 @@ function extractThinkDirective(body?: string): {
 	const cleaned = match
 		? body.replace(match[0], "").replace(/\s+/g, " ").trim()
 		: body.trim();
-	return { cleaned, thinkLevel };
+	return {
+		cleaned,
+		thinkLevel,
+		rawLevel: match?.[1],
+		hasDirective: !!match,
+	};
 }
 
 function isAbortTrigger(text?: string): boolean {
@@ -203,9 +210,12 @@ export async function getReplyFromConfig(
     IsNewSession: isNewSession ? "true" : "false",
   };
 
-	const { cleaned: thinkCleaned, thinkLevel: inlineThink } = extractThinkDirective(
-		sessionCtx.BodyStripped ?? sessionCtx.Body ?? "",
-	);
+	const {
+		cleaned: thinkCleaned,
+		thinkLevel: inlineThink,
+		rawLevel: rawThinkLevel,
+		hasDirective: hasThinkDirective,
+	} = extractThinkDirective(sessionCtx.BodyStripped ?? sessionCtx.Body ?? "");
 	sessionCtx.Body = thinkCleaned;
 	sessionCtx.BodyStripped = thinkCleaned;
 
@@ -215,7 +225,13 @@ export async function getReplyFromConfig(
 		(reply?.thinkingDefault as ThinkLevel | undefined);
 
 	// Directive-only message => persist session thinking level and return ack
-	if (inlineThink && !thinkCleaned) {
+	if (hasThinkDirective && !thinkCleaned) {
+		if (!inlineThink) {
+			cleanupTyping();
+			return {
+				text: `Unrecognized thinking level "${rawThinkLevel ?? ""}". Valid levels: off, minimal, low, medium, high.`,
+			};
+		}
 		if (sessionEntry && sessionStore && sessionKey) {
 			if (inlineThink === "off") {
 				delete sessionEntry.thinkingLevel;
@@ -226,8 +242,12 @@ export async function getReplyFromConfig(
 			sessionStore[sessionKey] = sessionEntry;
 			await saveSessionStore(storePath, sessionStore);
 		}
+		const ack =
+			inlineThink === "off"
+				? "Thinking disabled."
+				: `Thinking level set to ${inlineThink}.`;
 		cleanupTyping();
-		return { text: `Thinking level set to ${inlineThink}` };
+		return { text: ack };
 	}
 
   // Optional allowlist by origin number (E.164 without whatsapp: prefix)

src/index.core.test.ts

@@ -612,6 +612,82 @@ describe("config and templating", () => {
     expect(args.join(" ")).toContain("hi there think harder");
   });
 
+  it("confirms directive-only think level and skips command", async () => {
+    const runSpy = vi.spyOn(index, "runCommandWithTimeout").mockResolvedValue({
+      stdout: "ok",
+      stderr: "",
+      code: 0,
+      signal: null,
+      killed: false,
+    });
+    const cfg = {
+      inbound: {
+        reply: {
+          mode: "command" as const,
+          command: ["echo", "{{Body}}"],
+          agent: { kind: "claude" },
+        },
+      },
+    };
+
+    const ack = await index.getReplyFromConfig(
+      { Body: "/thinking high", From: "+1", To: "+2" },
+      undefined,
+      cfg,
+      runSpy,
+    );
+
+    expect(runSpy).not.toHaveBeenCalled();
+    expect(ack?.text).toBe("Thinking level set to high.");
+  });
+
+  it("rejects invalid directive-only think level without changing state", async () => {
+    const runSpy = vi.spyOn(index, "runCommandWithTimeout").mockResolvedValue({
+      stdout: "ok",
+      stderr: "",
+      code: 0,
+      signal: null,
+      killed: false,
+    });
+    const storeDir = await fs.promises.mkdtemp(
+      path.join(os.tmpdir(), "warelay-session-"),
+    );
+    const storePath = path.join(storeDir, "sessions.json");
+    const cfg = {
+      inbound: {
+        reply: {
+          mode: "command" as const,
+          command: ["echo", "{{Body}}"],
+          agent: { kind: "claude" },
+          session: { store: storePath },
+        },
+      },
+    };
+
+    const ack = await index.getReplyFromConfig(
+      { Body: "/thinking big", From: "+1", To: "+2" },
+      undefined,
+      cfg,
+      runSpy,
+    );
+
+    expect(runSpy).not.toHaveBeenCalled();
+    expect(ack?.text).toContain("Unrecognized thinking level \"big\"");
+
+    // Send another message; state should not carry any level.
+    const second = await index.getReplyFromConfig(
+      { Body: "hi", From: "+1", To: "+2" },
+      undefined,
+      cfg,
+      runSpy,
+    );
+    expect(runSpy).toHaveBeenCalledTimes(1);
+    const args = runSpy.mock.calls[0][0] as string[];
+    const bodyArg = args[args.length - 1];
+    expect(bodyArg).toBe("hi");
+    expect(second?.text).toBe("ok");
+  });
+
   it("uses global thinkingDefault when no directive or session override", async () => {
     const runSpy = vi.spyOn(index, "runCommandWithTimeout").mockResolvedValue({
       stdout: "ok",