diff --git a/docs/SYNC.md b/docs/SYNC.md
index 6bd6a84..c174c27 100644
--- a/docs/SYNC.md
+++ b/docs/SYNC.md
@@ -86,6 +86,7 @@ add a row or open a Contract Change Request.
 | `extensions/remote-control/apns/**` | T-1.10, Phase-2 T-2.9 (when iOS supplies tokens) |
 | `extensions/remote-control/cli/**` | T-1.3, T-1.7 |
 | `extensions/remote-control/config.ts` | T-1.7 |
+| `scripts/smoke/**` | T-1.0a (harness), any T-1.* task (add new test files) |
 | `docs/SYNC.md` | all (this file) |
 | `docs/PHASE-*.md` | nobody once a phase has started (frozen plan) — open a CCR to amend |
 | `docs/reference/**` | nobody during implementation — archival |
@@ -160,4 +161,5 @@ yyyy-mm-dd  @handle  T-x.y  what was done
 2026-05-15  @worker-phase0  T-0.*  Phase 0 spike complete. tmux+pipe-pane PoC validated. GREEN LIGHT for Phase 1. Report: reference/PHASE-0-report.md. Branch: feat/spike-stream (kept for reference, not merged).
 2026-05-15  @worker-phase0.5  T-0.5  Phase 0.5 spike complete. tmux control mode validated. VERDICT: Path B recommended. Report: reference/PHASE-0.5-report.md. Branch: feat/spike-tmux-cc (kept for reference, not merged).
 2026-05-15  @worker-t1.0  T-1.0  Server refactor scaffold complete. server.ts carved into server/{types,server,upgrade}.ts + server/routes/ stub. LEGACY html path preserved end-to-end. Branch: feat/p1-t1-0-server-refactor.
+2026-05-15  @worker-t1.0a  T-1.0a  Smoke test harness MVP complete. scripts/smoke/ with helpers.mjs + smoke.mjs. 6 tests: manifest, icon, GET/ auth+unauth, WS upgrade, process-alive. All green in ~1.4s. Uses python3 pty.spawn for PTY allocation. Branch: feat/p1-t1-0a-smoke.
 ```
diff --git a/package.json b/package.json
index 480c749..69fea3e 100644
--- a/package.json
+++ b/package.json
@@ -17,7 +17,8 @@
   "scripts": {
     "lint": "biome check --write .",
     "lint:check": "biome check .",
-    "prepare": "node .husky/install.mjs"
+    "prepare": "node .husky/install.mjs",
+    "smoke": "node --test scripts/smoke/smoke.mjs"
   },
   "devDependencies": {
     "@biomejs/biome": "^2.4.12",
diff --git a/scripts/smoke/README.md b/scripts/smoke/README.md
new file mode 100644
index 0000000..c2f568d
--- /dev/null
+++ b/scripts/smoke/README.md
@@ -0,0 +1,96 @@
+# Smoke Test Harness
+
+End-to-end smoke tests for the `remote-control` extension. These tests spawn
+a real `pi` subprocess with the extension loaded and hit the HTTP/WebSocket
+endpoints to verify they respond correctly.
+
+## Running
+
+```sh
+npm run smoke
+```
+
+Or directly:
+
+```sh
+node --test scripts/smoke/smoke.mjs
+```
+
+## What is tested (MVP — T-1.0a)
+
+| # | Test | Description |
+|---|------|-------------|
+| 1 | Server starts | pi spawns with `--remote-control`; TCP port opens within 12 s |
+| 2 | `GET /manifest.json` | 200, `application/manifest+json`, parses, has `name`/`short_name`/`start_url` |
+| 3 | `GET /icon.svg` | 200, `image/svg+xml`, body starts with `<svg` |
+| 4 | `GET /` (with token) | 302→200, `text/html`, contains HTML marker |
+| 5 | `GET /` (no token) | 403 Forbidden |
+| 6 | `WS /ws` (with token) | 101 upgrade, WebSocket enters OPEN state |
+| 7 | Process alive | pi hasn't crashed during the test run |
+| T | Teardown | SIGTERM pi, wait for exit, remove temp HOME |
+
+## Port
+
+Default port: **19876**. Override with the `SMOKE_PORT` environment variable:
+
+```sh
+SMOKE_PORT=20000 npm run smoke
+```
+
+## How it works
+
+The harness creates a temporary `HOME` directory containing:
+- `$HOME/.pi/remote-control/config.json` — `publicBaseUrl` + `bindAddress` pointing at `SMOKE_PORT`
+- `$HOME/.pi/remote-control/token` — a known deterministic token for auth
+
+`pi` is spawned with `HOME=<tmpdir>` so **no real `~/.pi` files are read or
+written**. The temp directory is deleted in the `after()` teardown hook even
+if tests fail.
+
+## Authentication
+
+The server requires either a valid session cookie or `?token=<value>` query
+parameter. The smoke tests pre-seed a known token (`smoke-test-token-deterministic-1234`)
+and pass it in the `?token=` parameter. No production auth logic is modified.
+
+## Adding new tests
+
+1. Create a new file `scripts/smoke/<feature>.test.mjs`
+2. Import helpers from `./helpers.mjs`
+3. Import your test file from `smoke.mjs` (or run it standalone with `node --test`)
+
+Example:
+
+```js
+// scripts/smoke/stream.test.mjs
+import { describe, it } from "node:test";
+import { openWebSocket, closeWebSocket } from "./helpers.mjs";
+
+export function registerStreamTests(port, token) {
+  describe("stream tests", () => {
+    it("WS /sessions/:id/stream → 101", async () => {
+      // ...
+    });
+  });
+}
+```
+
+## Flags used
+
+Same flags as `make dev`:
+```
+pi -nt -ne -ns -np -nc --no-session --offline -e extensions/remote-control --remote-control
+```
+
+## Troubleshooting
+
+**Port busy**: if `SMOKE_PORT` is already in use, the test will fail at the
+`waitForPort` step. Change the port: `SMOKE_PORT=20001 npm run smoke`.
+
+**pi not found**: ensure `pi` is on your `PATH`. Check with `which pi`.
+
+**Server not starting**: run with verbose output to see what pi logs:
+```sh
+node --test --reporter spec scripts/smoke/smoke.mjs
+```
+The port-wait error will include captured stdout/stderr from pi.
diff --git a/scripts/smoke/helpers.mjs b/scripts/smoke/helpers.mjs
new file mode 100644
index 0000000..c80e212
--- /dev/null
+++ b/scripts/smoke/helpers.mjs
@@ -0,0 +1,267 @@
+/**
+ * Smoke-test helpers — spawn-pi, wait-for-port, fetch, WebSocket.
+ *
+ * Designed to be imported by smoke.mjs and any future test files
+ * (e.g. scripts/smoke/stream.test.mjs). All helpers are stateless;
+ * the caller is responsible for lifecycle.
+ */
+
+import { spawn } from "node:child_process";
+import fs from "node:fs/promises";
+import { createRequire } from "node:module";
+import net from "node:net";
+import os from "node:os";
+import path from "node:path";
+
+// ── WebSocket (from project's bundled ws dependency) ─────────────────────────
+
+const _require = createRequire(import.meta.url);
+/** @type {import("ws")} */
+const wsModule = _require("ws");
+const WebSocket = wsModule.WebSocket ?? wsModule.default ?? wsModule;
+
+// ── Constants ─────────────────────────────────────────────────────────────────
+
+/** Milliseconds to wait for the TCP port to open before giving up. */
+const PORT_READY_TIMEOUT_MS = 12_000;
+/** Milliseconds between TCP-port-ready poll attempts. */
+const PORT_POLL_INTERVAL_MS = 100;
+
+// ── Temporary HOME setup ──────────────────────────────────────────────────────
+
+/**
+ * Create a minimal fake HOME directory that satisfies remote-control's config
+ * requirements:
+ *   $HOME/.pi/remote-control/config.json  — publicBaseUrl + bindAddress
+ *   $HOME/.pi/remote-control/token        — known token for auth
+ *
+ * @param {object} opts
+ * @param {number} opts.port  - TCP port to bind to.
+ * @param {string} opts.token - Auth token to pre-seed.
+ * @returns {Promise<string>} Path to the temp HOME directory.
+ */
+export async function createSmokeHome({ port, token }) {
+  const tmpBase = await fs.mkdtemp(path.join(os.tmpdir(), "pi-smoke-"));
+  const rcDir = path.join(tmpBase, ".pi", "remote-control");
+  await fs.mkdir(rcDir, { recursive: true });
+
+  const config = {
+    publicBaseUrl: `http://127.0.0.1:${port}`,
+    bindAddress: `127.0.0.1:${port}`,
+  };
+  await fs.writeFile(
+    path.join(rcDir, "config.json"),
+    `${JSON.stringify(config, null, 2)}\n`,
+    "utf8",
+  );
+  await fs.writeFile(path.join(rcDir, "token"), token, {
+    encoding: "utf8",
+    mode: 0o600,
+  });
+
+  return tmpBase;
+}
+
+/**
+ * Remove the temp HOME directory created by createSmokeHome.
+ * Silently ignores errors (e.g. already deleted).
+ *
+ * @param {string} tmpHome
+ */
+export async function removeSmokeHome(tmpHome) {
+  try {
+    await fs.rm(tmpHome, { recursive: true, force: true });
+  } catch {
+    /* ignore */
+  }
+}
+
+// ── Pi subprocess ─────────────────────────────────────────────────────────────
+
+/**
+ * Spawn a `pi` process with the remote-control extension loaded.
+ *
+ * Uses the same flags as `make dev` plus `--remote-control` to auto-start
+ * the HTTP server. Sets HOME to the given fake home so config/token paths
+ * resolve correctly without touching the real ~/.pi directory.
+ *
+ * Pi is a TUI application that requires a PTY (pseudo-terminal) to enter its
+ * interactive session mode and fire `session_start`. We use Python's built-in
+ * `pty.spawn` to allocate a PTY for pi; this is available on all macOS/Linux
+ * systems without any additional dependencies.
+ *
+ * @param {object} opts
+ * @param {string} opts.extensionPath  - Absolute path to the extension dir.
+ * @param {string} opts.fakeHome       - Path to the fake HOME directory.
+ * @returns {{ proc: import("node:child_process").ChildProcess, logs: string[] }}
+ */
+export function spawnPi({ extensionPath, fakeHome }) {
+  const logs = [];
+
+  // Python script that allocates a PTY and spawns pi inside it.
+  // Using pty.spawn() keeps the child alive (no EOF injection like `script` does).
+  const pyScript = [
+    "import os, pty",
+    `os.environ['HOME'] = ${JSON.stringify(fakeHome)}`,
+    `pty.spawn(['pi', '-nt', '-ne', '-ns', '-np', '-nc', '--no-session', '--offline', '-e', ${JSON.stringify(extensionPath)}, '--remote-control'])`,
+  ].join("\n");
+
+  const proc = spawn("python3", ["-c", pyScript], {
+    env: { ...process.env, HOME: fakeHome },
+    stdio: ["ignore", "pipe", "pipe"],
+  });
+
+  const capture = (chunk) => {
+    logs.push(chunk.toString());
+  };
+  proc.stdout.on("data", capture);
+  proc.stderr.on("data", capture);
+
+  return { proc, logs };
+}
+
+/**
+ * Kill a pi process and wait for it to exit.
+ * Sends SIGTERM first; if it doesn't exit within 3 s, sends SIGKILL.
+ *
+ * @param {import("node:child_process").ChildProcess} proc
+ * @returns {Promise<number|null>} The exit code (or null if killed by signal).
+ */
+export function killPi(proc) {
+  return new Promise((resolve) => {
+    if (proc.exitCode !== null) {
+      resolve(proc.exitCode);
+      return;
+    }
+
+    let settled = false;
+    const settle = (code) => {
+      if (!settled) {
+        settled = true;
+        clearTimeout(sigkillTimer);
+        resolve(code ?? null);
+      }
+    };
+
+    proc.once("exit", (code) => settle(code));
+
+    proc.kill("SIGTERM");
+
+    // Safety: escalate to SIGKILL after 3 s
+    const sigkillTimer = setTimeout(() => {
+      try {
+        proc.kill("SIGKILL");
+      } catch {
+        /* already dead */
+      }
+    }, 3_000);
+  });
+}
+
+// ── Port readiness ────────────────────────────────────────────────────────────
+
+/**
+ * Poll a TCP port until it accepts connections or the timeout expires.
+ *
+ * @param {object} opts
+ * @param {number} opts.port
+ * @param {string} [opts.host]       - Default "127.0.0.1".
+ * @param {number} [opts.timeoutMs]  - Default PORT_READY_TIMEOUT_MS.
+ * @param {number} [opts.intervalMs] - Default PORT_POLL_INTERVAL_MS.
+ * @returns {Promise<void>} Resolves when port is open; rejects on timeout.
+ */
+export function waitForPort({
+  port,
+  host = "127.0.0.1",
+  timeoutMs = PORT_READY_TIMEOUT_MS,
+  intervalMs = PORT_POLL_INTERVAL_MS,
+}) {
+  return new Promise((resolve, reject) => {
+    const deadline = Date.now() + timeoutMs;
+
+    const attempt = () => {
+      const sock = net.createConnection({ port, host });
+
+      sock.once("connect", () => {
+        sock.destroy();
+        resolve();
+      });
+
+      sock.once("error", () => {
+        sock.destroy();
+        if (Date.now() >= deadline) {
+          reject(
+            new Error(
+              `Port ${host}:${port} did not open within ${timeoutMs} ms`,
+            ),
+          );
+        } else {
+          setTimeout(attempt, intervalMs);
+        }
+      });
+    };
+
+    attempt();
+  });
+}
+
+// ── HTTP helpers ──────────────────────────────────────────────────────────────
+
+/**
+ * Build the base URL for the smoke server.
+ *
+ * @param {number} port
+ * @returns {string}
+ */
+export function baseUrl(port) {
+  return `http://127.0.0.1:${port}`;
+}
+
+/**
+ * Fetch a URL and return the response plus text body.
+ * Throws if the network request itself fails.
+ *
+ * @param {string} url
+ * @param {RequestInit} [init]
+ * @returns {Promise<{ res: Response; body: string }>}
+ */
+export async function fetchText(url, init) {
+  const res = await fetch(url, init);
+  const body = await res.text();
+  return { res, body };
+}
+
+// ── WebSocket helpers ─────────────────────────────────────────────────────────
+
+/**
+ * Open a WebSocket connection and wait for either an `open` or `error` event.
+ * Resolves with the WebSocket instance on success.
+ * Rejects with the error on failure.
+ *
+ * @param {string} url  - WebSocket URL (ws:// or wss://).
+ * @returns {Promise<import("ws").WebSocket>}
+ */
+export function openWebSocket(url) {
+  return new Promise((resolve, reject) => {
+    const ws = new WebSocket(url);
+    ws.once("open", () => resolve(ws));
+    ws.once("error", reject);
+  });
+}
+
+/**
+ * Close a WebSocket and wait for the close event.
+ *
+ * @param {import("ws").WebSocket} ws
+ * @returns {Promise<void>}
+ */
+export function closeWebSocket(ws) {
+  return new Promise((resolve) => {
+    if (ws.readyState === ws.constructor.CLOSED) {
+      resolve();
+      return;
+    }
+    ws.once("close", () => resolve());
+    ws.close();
+  });
+}
diff --git a/scripts/smoke/smoke.mjs b/scripts/smoke/smoke.mjs
new file mode 100644
index 0000000..ed909d4
--- /dev/null
+++ b/scripts/smoke/smoke.mjs
@@ -0,0 +1,249 @@
+/**
+ * Smoke test — end-to-end validation of the remote-control HTTP/WS server.
+ *
+ * Runs with: node --test scripts/smoke/smoke.mjs
+ * Or:        npm run smoke
+ *
+ * What is tested (MVP):
+ *   1. Server starts  — pi spawns with --remote-control and the HTTP port opens.
+ *   2. GET /manifest.json — 200, application/manifest+json, parses, has name/short_name/start_url.
+ *   3. GET /icon.svg       — 200, image/svg+xml, body starts with <svg.
+ *   4. GET /               — 200 (with auth token), text/html, contains HTML marker.
+ *   5. WS /ws              — successful 101 upgrade (with auth token). Close cleanly.
+ *   6. Teardown            — SIGTERM pi, process exits.
+ *
+ * Auth strategy:
+ *   The server requires a token on GET / and WS /ws. We pre-seed a known token
+ *   in a temporary HOME directory ($HOME/.pi/remote-control/token) and pass it
+ *   via the ?token= query parameter using the existing mechanism. No production
+ *   code is modified.
+ *
+ * Port strategy:
+ *   We write bindAddress + publicBaseUrl to the temporary config so the server
+ *   binds to a deterministic port (SMOKE_PORT env, default 19876). No real
+ *   ~/.pi files are touched.
+ */
+
+import assert from "node:assert/strict";
+import path from "node:path";
+import { after, before, describe, it } from "node:test";
+import { fileURLToPath } from "node:url";
+import {
+  baseUrl,
+  closeWebSocket,
+  createSmokeHome,
+  fetchText,
+  killPi,
+  openWebSocket,
+  removeSmokeHome,
+  spawnPi,
+  waitForPort,
+} from "./helpers.mjs";
+
+// ── Configuration ─────────────────────────────────────────────────────────────
+
+const SMOKE_PORT = Number(process.env.SMOKE_PORT ?? 19876);
+const SMOKE_TOKEN = "smoke-test-token-deterministic-1234";
+
+const EXTENSION_PATH = path.resolve(
+  path.dirname(fileURLToPath(import.meta.url)),
+  "../../extensions/remote-control",
+);
+
+// ── Suite ─────────────────────────────────────────────────────────────────────
+
+describe("remote-control smoke tests", () => {
+  /** @type {import("node:child_process").ChildProcess} */
+  let proc;
+  /** @type {string} */
+  let fakeHome;
+  /** @type {string[]} */
+  let logs;
+
+  before(async () => {
+    // Create temp HOME with config + token
+    fakeHome = await createSmokeHome({ port: SMOKE_PORT, token: SMOKE_TOKEN });
+
+    // Spawn pi
+    ({ proc, logs } = spawnPi({ extensionPath: EXTENSION_PATH, fakeHome }));
+
+    // Wait for the HTTP server to open the TCP port
+    try {
+      await waitForPort({ port: SMOKE_PORT });
+    } catch (err) {
+      // Attach captured logs to the error for easy debugging
+      const captured = logs.join("");
+      throw new Error(
+        `${err.message}\n\n--- pi stdout/stderr ---\n${captured || "(empty)"}`,
+      );
+    }
+  });
+
+  after(async () => {
+    // Always clean up — kill pi and remove temp HOME
+    if (proc) {
+      await killPi(proc);
+    }
+    if (fakeHome) {
+      await removeSmokeHome(fakeHome);
+    }
+  });
+
+  // ── Test 1: manifest.json ───────────────────────────────────────────────────
+
+  it("GET /manifest.json → 200 application/manifest+json with required fields", async () => {
+    const { res, body } = await fetchText(
+      `${baseUrl(SMOKE_PORT)}/manifest.json`,
+    );
+
+    assert.equal(res.status, 200, `Expected 200, got ${res.status}`);
+
+    const ct = res.headers.get("content-type") ?? "";
+    assert.ok(
+      ct.includes("application/manifest+json"),
+      `Expected content-type application/manifest+json, got: ${ct}`,
+    );
+
+    let manifest;
+    try {
+      manifest = JSON.parse(body);
+    } catch {
+      assert.fail(
+        `manifest.json body is not valid JSON: ${body.slice(0, 200)}`,
+      );
+    }
+
+    assert.ok(
+      typeof manifest.name === "string" && manifest.name.length > 0,
+      "manifest.name must be a non-empty string",
+    );
+    assert.ok(
+      typeof manifest.short_name === "string" && manifest.short_name.length > 0,
+      "manifest.short_name must be a non-empty string",
+    );
+    assert.ok(
+      typeof manifest.start_url === "string" && manifest.start_url.length > 0,
+      "manifest.start_url must be a non-empty string",
+    );
+  });
+
+  // ── Test 2: icon.svg ────────────────────────────────────────────────────────
+
+  it("GET /icon.svg → 200 image/svg+xml, body starts with <svg", async () => {
+    const { res, body } = await fetchText(`${baseUrl(SMOKE_PORT)}/icon.svg`);
+
+    assert.equal(res.status, 200, `Expected 200, got ${res.status}`);
+
+    const ct = res.headers.get("content-type") ?? "";
+    assert.ok(
+      ct.includes("image/svg+xml"),
+      `Expected content-type image/svg+xml, got: ${ct}`,
+    );
+
+    assert.ok(
+      body.trimStart().startsWith("<svg"),
+      `Expected body to start with <svg, got: ${body.slice(0, 100)}`,
+    );
+  });
+
+  // ── Test 3: root with auth ──────────────────────────────────────────────────
+
+  it("GET / (with token) → 200 text/html containing HTML marker", async () => {
+    const url = `${baseUrl(SMOKE_PORT)}/?token=${SMOKE_TOKEN}`;
+    // The server issues a 302 redirect on first token auth (sets session cookie),
+    // then serves 200 on the redirect target. Follow redirects manually to keep
+    // cookies across the redirect chain.
+    const cookieJar = {};
+
+    // First request: expect 302
+    const first = await fetch(url, { redirect: "manual" });
+
+    let body;
+    if (first.status === 302) {
+      // Extract session cookie
+      for (const [name, value] of first.headers.entries()) {
+        if (name.toLowerCase() === "set-cookie") {
+          const match = value.match(/^([^=]+)=([^;]+)/);
+          if (match) cookieJar[match[1]] = match[2];
+        }
+      }
+      const location = first.headers.get("location") ?? "/";
+      const cookieHeader = Object.entries(cookieJar)
+        .map(([k, v]) => `${k}=${v}`)
+        .join("; ");
+
+      const second = await fetch(`${baseUrl(SMOKE_PORT)}${location}`, {
+        headers: cookieHeader ? { Cookie: cookieHeader } : {},
+      });
+      assert.equal(
+        second.status,
+        200,
+        `Expected 200 on redirect target, got ${second.status}`,
+      );
+      const ct = second.headers.get("content-type") ?? "";
+      assert.ok(
+        ct.includes("text/html"),
+        `Expected content-type text/html, got: ${ct}`,
+      );
+      body = await second.text();
+    } else {
+      assert.equal(first.status, 200, `Expected 200, got ${first.status}`);
+      const ct = first.headers.get("content-type") ?? "";
+      assert.ok(
+        ct.includes("text/html"),
+        `Expected content-type text/html, got: ${ct}`,
+      );
+      body = await first.text();
+    }
+
+    // Check for a marker from html.ts — the title is always present
+    assert.ok(
+      body.includes("<!DOCTYPE html>"),
+      "Expected body to contain <!DOCTYPE html>",
+    );
+    assert.ok(
+      body.includes("remote-control") ||
+        body.includes("Pi Remote") ||
+        body.includes("π"),
+      "Expected body to contain a known HTML marker (remote-control / Pi Remote / π)",
+    );
+  });
+
+  // ── Test 4: 403 on unauthenticated root ─────────────────────────────────────
+
+  it("GET / (no token) → 403 Forbidden", async () => {
+    const { res } = await fetchText(`${baseUrl(SMOKE_PORT)}/`);
+    assert.equal(
+      res.status,
+      403,
+      `Expected 403 without token, got ${res.status}`,
+    );
+  });
+
+  // ── Test 5: WebSocket upgrade ───────────────────────────────────────────────
+
+  it("WS /ws (with token) → successful 101 upgrade", async () => {
+    const wsUrl = `ws://127.0.0.1:${SMOKE_PORT}/ws?token=${SMOKE_TOKEN}`;
+
+    // First, get a session cookie via HTTP (WS token auth also works directly
+    // since isAuthenticated checks URL searchParams on the Upgrade request)
+    const ws = await openWebSocket(wsUrl);
+
+    assert.ok(
+      ws.readyState === ws.constructor.OPEN,
+      "WebSocket should be in OPEN state after successful handshake",
+    );
+
+    await closeWebSocket(ws);
+  });
+
+  // ── Test 6: teardown (handled in after(), verified here) ───────────────────
+
+  it("pi process is alive during tests", () => {
+    assert.equal(
+      proc.exitCode,
+      null,
+      "pi process should still be running during tests",
+    );
+  });
+});