optimistic submit: one Thinking placeholder everywhere — spinner from the instant of submit

components/chat.tsx

@@ -186,7 +186,7 @@ export function Chat({
 	// (core/view.ts projectView); sends are ONE explicit input event each
 	// ({chatId, input} — the stash indirection died with the SDK), and the
 	// turn stream is the VERBATIM AgentEvent passthrough the server emits.
-	const { messages, nativeMessages, send, submitAnswer, setMessages, adoptRecord, status, error, reattaching, stop, clearError, resumeStream, setReattachSettled } =
+	const { messages, nativeMessages, send, submitAnswer, setMessages, adoptRecord, status, error, stop, clearError, resumeStream, setReattachSettled } =
 		useChatSession({ chatId, initialMessages, initiallyInFlight });
 
 	// The reattach settled terminal → the sync-and-continue seam (below).
@@ -1177,28 +1177,26 @@ export function Chat({
 								</Fragment>
 							))}
 
-							{/* The pre-first-chunk line only (owner, streaming round
-							    2026-10-01): once a tool call starts writing, its LIVE card
-							    carries the activity inline — the old bottom tool-activity
-							    line retired rather than double-render. Same glimmer recipe
-							    as the thinking row: duration 1. The REATTACH variant
-							    (reattach round 2026-10-02): while a fresh mount reattaches
-							    to a server-side turn, the placeholder says what is actually
-							    happening — Reattaching… + the working-state spinner —
-							    instead of a bare Thinking shimmer. */}
-							{(status === "submitted" || turnInFlight) &&
-								(reattaching ? (
-									<span className="flex items-center gap-2">
-										<BrailleSpinner label="Reattaching to the running turn" />
-										<Shimmer duration={1} className="text-sm">
-											Reattaching…
-										</Shimmer>
-									</span>
-								) : (
+							{/* THE pre-first-chunk placeholder, ONE grammar everywhere
+							    (owner, optimistic round 2026-10-02): spinner + shimmered
+							    Thinking… from the instant anything is submitted (send,
+							    answer, reattach — status flips synchronously, so it shows
+							    before the first token, however slow the provider's
+							    connection) until the first event lands, then it hands off
+							    to the live stream — minimal change: the collapsible
+							    reasoning row carries the SAME look, now with content.
+							    Never collapsible itself (there is nothing to show yet).
+							    Once a tool call starts writing, its LIVE card carries the
+							    activity inline (the bottom tool-activity line retired,
+							    streaming round 2026-10-01). */}
+							{(status === "submitted" || turnInFlight) && (
+								<span className="flex items-center gap-2">
+									<BrailleSpinner label="Thinking" />
 									<Shimmer duration={1} className="text-sm">
 										Thinking…
 									</Shimmer>
-								))}
+								</span>
+							)}
 							{error && (
 								<div className="rounded-lg border border-destructive/50 bg-destructive/10 px-3 py-2 text-sm">
 									Something went wrong: {error.message}

components/session-core.ts

@@ -140,10 +140,6 @@ export interface SessionState {
 	nativeMessages: LhMessage[];
 	status: SessionStatus;
 	error: { message: string } | null;
-	/** A reattach handshake is in flight (resumeStream, no events yet):
-	 *  the view shows the honest “Reattaching…” placeholder instead of a
-	 *  bare Thinking shimmer (owner, reattach round 2026-10-02). */
-	reattaching: boolean;
 }
 
 export interface SessionModelOptions extends SessionModelDeps {
@@ -178,9 +174,6 @@ export class SessionModel {
 	private streamingMessageId: string | null = null;
 	private statusValue: SessionStatus = "ready";
 	private errorValue: { message: string } | null = null;
-	/** True from resumeStream() entry until its first event / settle /
-	 *  error — the handshake window (see SessionState.reattaching). */
-	private reattachingValue = false;
 	// The single live consume (POST response or reattach stream): a newer
 	// consume cancels the older — one reader at a time.
 	private consumeAbort: AbortController | null = null;
@@ -216,7 +209,6 @@ export class SessionModel {
 			nativeMessages: [...this.base, ...this.tail],
 			status: this.statusValue,
 			error: this.errorValue,
-			reattaching: this.reattachingValue,
 		};
 	}
 
@@ -393,7 +385,6 @@ export class SessionModel {
 				}
 				if (!sawEvent) {
 					sawEvent = true;
-					this.reattachingValue = false; // first event: content, not a handshake
 					if (this.statusValue !== "error") this.setStatus("streaming");
 				}
 				this.applyWireEvent(event);
@@ -401,7 +392,6 @@ export class SessionModel {
 		} finally {
 			this.streamingIds = new Set();
 			this.executions = new Map();
-			this.reattachingValue = false; // settled/aborted: no handshake anymore
 			if (this.statusValue !== "error") this.setStatus("ready");
 		}
 	}
@@ -423,7 +413,6 @@ export class SessionModel {
 		this.consumeAbort?.abort();
 		const controller = new AbortController();
 		this.consumeAbort = controller;
-		this.reattachingValue = true;
 		this.setStatus("submitted");
 		try {
 			if (refetchRecordFirst) {
@@ -447,7 +436,6 @@ export class SessionModel {
 			await this.consumeStream(res);
 		} catch (err) {
 			if ((err as Error).name === "AbortError") return; // a newer consume won
-			this.reattachingValue = false;
 			this.setError((err as Error).message);
 			this.setStatus("error");
 		}
@@ -465,7 +453,6 @@ export class SessionModel {
 		const controller = new AbortController();
 		this.consumeAbort = controller;
 		this.setError(null);
-		this.reattachingValue = false; // an aborted handshake is not a placeholder
 		this.setStatus("submitted");
 		// The optimistic appends — exactly the messages the server's
 		// write-ahead will persist (inputAppends), with LOCAL ids so
@@ -513,7 +500,6 @@ export class SessionModel {
 	stop(): void {
 		this.consumeAbort?.abort();
 		this.consumeAbort = null;
-		this.reattachingValue = false;
 		this.streamingIds = new Set();
 		this.streamingMessageId = null;
 		this.executions = new Map();

components/session.ts

@@ -86,7 +86,6 @@ export function useChatSession({ chatId, initialMessages, initiallyInFlight }: U
 		nativeMessages: state.nativeMessages,
 		status: state.status,
 		error: state.error,
-		reattaching: state.reattaching,
 		send,
 		submitAnswer,
 		setMessages,

tests/session-core.test.ts

@@ -492,28 +492,26 @@ describe("resumeStream (the reattach path)", () => {
 		// (the earlier test in this block pins that order).
 	});
 
-	it("reattaching is honest: true during the handshake, false once events flow", async () => {
+	it("OPTIMISTIC SUBMIT (owner, optimistic round 2026-10-02): send/reattach flip status synchronously — the Thinking… placeholder shows before the first token, however slow the provider", async () => {
 		let release!: (r: Response) => void;
 		const gate = new Promise<Response>((res) => (release = res));
 		globalThis.fetch = (async (input: RequestInfo | URL) => {
 			const url = String(input);
-			if (url === "/api/chats/chat_x") return gate; // the record fetch hangs
-			if (url === "/api/chats/chat_x/stream")
-				return sseResponse(
-					{ type: "message_start", message: { role: "assistant", content: [{ type: "text", text: "hi" }] } },
-					{ type: "agent_end", messages: [] },
-					"[DONE]",
-				);
+			if (url === "/api/chats/chat_x") return gate; // the POST hangs
 			throw new Error(`unexpected fetch: ${url}`);
 		}) as typeof globalThis.fetch;
 		const m = model();
-		const p = m.resumeStream(); // runs sync to the first await (the gated fetch)
-		assert.equal(m.getState().reattaching, true, "mid-handshake: the placeholder is Reattaching…");
-		assert.equal(m.getState().status, "submitted");
+		// send() runs synchronously to its first await — status is already
+		// "submitted" (and the optimistic user bubble is appended) before
+		// the server has answered ANYTHING.
+		const p = m.send({ type: "text", text: "q" });
+		assert.equal(m.getState().status, "submitted", "the placeholder is live pre-first-chunk");
+		assert.equal(m.getState().messages.at(-1)!.role, "user", "the optimistic bubble is up");
 		release(Response.json({ messages: [] }));
 		await p;
-		assert.equal(m.getState().reattaching, false, "first event landed: content, not a handshake");
-		assert.equal(m.getState().status, "ready");
+		// the reattach path is the same synchronous flip (resumeStream sets
+		// submitted at entry, before its fetches) — pinned by the handshake
+		// test above reading status mid-fetch.
 	});
 
 	it("turn-settled fires the settle hook and ends cleanly", async () => {