diff --git a/apps/pwa/src/routes/moshpit.mjs b/apps/pwa/src/routes/moshpit.mjs
index 0bc76b6..08e1741 100644
--- a/apps/pwa/src/routes/moshpit.mjs
+++ b/apps/pwa/src/routes/moshpit.mjs
@@ -15,6 +15,7 @@
 import { Router } from "express";
 import { page, footer, appBar, esc } from "../lib/html.mjs";
 import { requireAuth, csrfInput } from "../lib/session.mjs";
+import { bearer, userForApiKey } from "../lib/apikey.mjs";
 import { balance } from "../lib/credits.mjs";
 import { resolverConfig } from "../lib/moshpit-resolvers.mjs";
 import { landingFor } from "../lib/moshpit-landing.mjs";
@@ -74,6 +75,31 @@ export const moshpitRouter = Router();
 const bad = (res, error, status = 400) => res.status(status).json({ error });
 const unauthorized = (res) => res.status(401).json({ error: "sign in first" });
 
+/**
+ * The machine half of the namespace.
+ *
+ * Everything under /api/moshpit is described at the top of this file as an API,
+ * and it was one only if you happened to have a browser cookie. `moshcode`
+ * holds an API key that /api/me and /api/sessions both accept; every endpoint
+ * here answered that same key with 401, so the namespace was the one part of
+ * the product no script could touch.
+ *
+ * Same helper, same keys, same 401 when there is no key -- this is not a new
+ * way in, it stops one router being the exception. A cookie session still wins
+ * when both are present, because that is the caller who is already identified.
+ *
+ * Only /api/moshpit. The /pit pages are browser routes: they are CSRF-guarded
+ * form posts, and a bearer token has no business standing in for a session
+ * there.
+ */
+moshpitRouter.use("/api/moshpit", async (req, _res, next) => {
+  if (!req.user) {
+    const user = await userForApiKey(bearer(req));
+    if (user) req.user = user;
+  }
+  next();
+});
+
 /* ---------- API ---------- */
 
 /**
diff --git a/apps/pwa/test/moshpit-api-key.test.mjs b/apps/pwa/test/moshpit-api-key.test.mjs
new file mode 100644
index 0000000..a71b31d
--- /dev/null
+++ b/apps/pwa/test/moshpit-api-key.test.mjs
@@ -0,0 +1,165 @@
+// The namespace API, driven by a machine.
+//
+// /api/moshpit/* reads as an API and behaved like one only for a browser: the
+// same API key that `moshcode whoami` uses against /api/me got 401 from every
+// endpoint here, so the namespace was the one part of the product no script
+// could touch.
+//
+// These tests pin both halves of that: a key works, and the absence of one
+// still does not.
+import assert from "node:assert/strict";
+import fs from "node:fs";
+import { mkdtempSync } from "node:fs";
+import { tmpdir } from "node:os";
+import path from "node:path";
+import { createRequire } from "node:module";
+import test from "node:test";
+
+const require = createRequire(import.meta.url);
+let deps = null;
+try {
+  deps = { express: require("express"), cookieParser: require("cookie-parser") };
+} catch {
+  deps = null;
+}
+
+const workdir = mkdtempSync(path.join(tmpdir(), "moshcode-pit-apikey-test-"));
+process.env.DATABASE_URL = `file:${path.join(workdir, "test.db")}`;
+process.env.SESSION_SECRET = "test-secret";
+
+async function boot() {
+  const { migrate } = await import("../src/migrate.mjs");
+  await migrate();
+  const { run, db } = await import("../src/db.mjs");
+  const { sessionMiddleware, csrfGuard } = await import("../src/lib/session.mjs");
+  const { moshpitRouter } = await import("../src/routes/moshpit.mjs");
+  const { createApiKey } = await import("../src/lib/apikey.mjs");
+
+  await run(`INSERT OR REPLACE INTO users (id, email, display_name, created_at) VALUES ('u1','a@b.c','one',1)`);
+  await run(`INSERT OR REPLACE INTO users (id, email, display_name, created_at) VALUES ('u2','x@y.z','two',1)`);
+  await run(`INSERT INTO moshpit_tlds (tld,user_id,owner_email,created_at) VALUES ('held','u1','a@b.c',1)`);
+  await run(`INSERT INTO moshpit_tlds (tld,user_id,owner_email,created_at) VALUES ('theirs','u2','x@y.z',1)`);
+
+  const keyOne = (await createApiKey("u1", "cli one")).plaintext;
+  const keyTwo = (await createApiKey("u2", "cli two")).plaintext;
+
+  // The real middleware stack, so the CSRF guard gets a vote on these requests
+  // exactly as it does in production.
+  const app = deps.express();
+  app.use(deps.express.json());
+  app.use(deps.express.urlencoded({ extended: false }));
+  app.use(deps.cookieParser());
+  app.use(sessionMiddleware);
+  app.use(csrfGuard);
+  app.use(moshpitRouter);
+  const server = await new Promise((resolve) => {
+    const s = app.listen(0, "127.0.0.1", () => resolve(s));
+  });
+  const base = `http://127.0.0.1:${server.address().port}`;
+
+  const call = (token) => async (method, p, body) => {
+    const res = await fetch(`${base}${p}`, {
+      method,
+      headers: {
+        "content-type": "application/json",
+        ...(token ? { authorization: `Bearer ${token}` } : {}),
+      },
+      body: body === undefined ? undefined : JSON.stringify(body),
+    });
+    const text = await res.text();
+    let json = null;
+    try { json = JSON.parse(text); } catch { /* HTML error page */ }
+    return { status: res.status, json, text };
+  };
+
+  return { server, db, one: call(keyOne), two: call(keyTwo), anon: call(null) };
+}
+
+let booted = null;
+const app = () => (booted ||= boot());
+
+test.after(() => {
+  if (!booted) return;
+  booted.then(({ server, db }) => { server.close(); db.close?.(); })
+    .finally(() => { try { fs.rmSync(workdir, { recursive: true, force: true }); } catch { /* noop */ } });
+});
+
+const skip = { skip: !deps && "apps/pwa deps not installed" };
+
+test("api key: reading your own endings no longer needs a browser", skip, async () => {
+  const { one, anon } = await app();
+
+  const mine = await one("GET", "/api/moshpit/tlds?mine=1");
+  assert.equal(mine.status, 200);
+  assert.deepEqual(mine.json.tlds.map((t) => t.tld), ["held"]);
+
+  // The absence of a key is still 401 — this widened who can authenticate, not
+  // whether anyone has to.
+  assert.equal((await anon("GET", "/api/moshpit/tlds?mine=1")).status, 401);
+});
+
+test("api key: claiming an ending works from a script", skip, async () => {
+  const { one } = await app();
+  const res = await one("POST", "/api/moshpit/tlds", { tld: "claimed" });
+  assert.equal(res.status, 201, res.text);   // 201: it created something
+
+  const mine = await one("GET", "/api/moshpit/tlds?mine=1");
+  assert.ok(mine.json.tlds.map((t) => t.tld).includes("claimed"));
+});
+
+test("api key: a write with no key is refused, not silently accepted", skip, async () => {
+  const { anon } = await app();
+  const res = await anon("POST", "/api/moshpit/tlds", { tld: "nokey" });
+  assert.equal(res.status, 401);
+
+  const { anon: check } = await app();
+  const still = await check("GET", "/api/moshpit/tlds/nokey");
+  assert.equal(still.json.available, true, "nothing was written");
+});
+
+test("api key: one key cannot act on another account's ending", skip, async () => {
+  const { two } = await app();
+  // u2 holds .theirs, not .held. Authenticating is not authorising.
+  const res = await two("PUT", "/api/moshpit/tlds/held/alias", { to: "theirs" });
+  assert.notEqual(res.status, 200);
+
+  const { one } = await app();
+  const mine = await one("GET", "/api/moshpit/tlds?mine=1");
+  const held = mine.json.tlds.find((t) => t.tld === "held");
+  assert.equal(held.alias_of, null, "somebody else's key did not repoint it");
+});
+
+test("api key: a made-up key is nobody", skip, async () => {
+  const { server } = await app();
+  const base = `http://127.0.0.1:${server.address().port}`;
+  const res = await fetch(`${base}/api/moshpit/tlds?mine=1`, {
+    headers: { authorization: "Bearer not-a-real-key" },
+  });
+  assert.equal(res.status, 401);
+});
+
+test("api key: names can be minted and pointed from a script", skip, async () => {
+  const { one } = await app();
+  assert.equal((await one("POST", "/api/moshpit/tlds/held/names", { label: "blue" })).status, 201);
+
+  const pointed = await one("PUT", "/api/moshpit/tlds/held/names", { label: "blue", target: "203.0.113.7" });
+  assert.equal(pointed.status, 200, pointed.text);
+
+  const resolved = await one("GET", "/api/moshpit/resolve?name=blue.held");
+  assert.equal(resolved.json.target, "203.0.113.7");
+});
+
+test("api key: the browser routes are still browser routes", skip, async () => {
+  const { one } = await app();
+  // /pit/claim is a CSRF-guarded form post. A bearer token must not stand in
+  // for a session there — the guard runs before the router and should reject it.
+  const res = await fetch(`http://127.0.0.1:${(await app()).server.address().port}/pit/claim`, {
+    method: "POST",
+    headers: { "content-type": "application/x-www-form-urlencoded", authorization: "Bearer whatever" },
+    body: "tld=sneaky",
+  });
+  assert.equal(res.status, 403, "csrf guard still owns the form routes");
+
+  const check = await one("GET", "/api/moshpit/tlds/sneaky");
+  assert.equal(check.json.available, true, "nothing was claimed");
+});