diff --git a/changelog.d/fixes/7522-codex-import-validate-refresh.md b/changelog.d/fixes/7522-codex-import-validate-refresh.md
new file mode 100644
index 0000000000..73ae7b0f20
--- /dev/null
+++ b/changelog.d/fixes/7522-codex-import-validate-refresh.md
@@ -0,0 +1 @@
+- The Codex account import (`POST /api/oauth/codex/import`) now validates each record's `refresh_token` against OpenAI's OAuth endpoint before persisting the connection: an already-invalidated session (`refresh_token_invalidated` / a dead `auth.json`) is rejected with a clear "run `codex login` again and re-import" message instead of importing as `active` and failing confusingly on first use. Valid tokens import as before, with any rotated tokens applied (#7522).
diff --git a/src/app/api/oauth/codex/import/route.ts b/src/app/api/oauth/codex/import/route.ts
index 5e37803696..a7302a3a6d 100644
--- a/src/app/api/oauth/codex/import/route.ts
+++ b/src/app/api/oauth/codex/import/route.ts
@@ -4,6 +4,63 @@ import { normalizeCodexImportRecord, flattenCodexImportPayload } from "@/lib/oau
 import { createProviderConnection } from "@/models";
 import { isAuthRequired, isAuthenticated } from "@/shared/utils/apiAuth";
 import { sanitizeErrorMessage } from "@omniroute/open-sse/utils/error.ts";
+import { refreshCodexToken, isUnrecoverableRefreshError } from "@omniroute/open-sse/services/tokenRefresh.ts";
+
+/**
+ * Message returned when the imported record's refresh_token is already dead
+ * (rotated/consumed/expired) — see #7522. Persisting a connection whose
+ * refresh_token can never succeed leaves an `active` connection that fails
+ * confusingly on first real use, long after the import looked successful.
+ */
+const EXPIRED_SESSION_MESSAGE =
+  "This Codex session has expired — run `codex login` again and re-import. " +
+  "(Esta sessão do Codex expirou — rode `codex login` novamente e reimporte.)";
+
+/**
+ * Validate a normalized Codex import record's refresh_token against OpenAI's
+ * OAuth token endpoint before it is persisted as a connection. Reuses
+ * `refreshCodexToken()` (the same rotating-refresh-token exchange used by the
+ * runtime token-refresh path) instead of re-implementing the POST — the
+ * exchange call itself is free (no model/quota usage).
+ *
+ * Returns `null` when the token is valid (or the check was inconclusive, e.g.
+ * a transient network error) — the import proceeds normally in that case,
+ * optionally with rotated tokens already applied to `payload`. Returns an
+ * error string when the refresh_token is confirmed dead and the import
+ * should be rejected.
+ */
+async function validateCodexRefreshToken(
+  payload: { accessToken: string; refreshToken: string },
+): Promise<string | null> {
+  let refreshResult: unknown;
+  try {
+    refreshResult = await refreshCodexToken(payload.refreshToken, undefined, null);
+  } catch {
+    // Network/transport failure: inconclusive, do not block the import.
+    return null;
+  }
+
+  if (isUnrecoverableRefreshError(refreshResult)) {
+    return EXPIRED_SESSION_MESSAGE;
+  }
+
+  if (
+    refreshResult &&
+    typeof refreshResult === "object" &&
+    typeof (refreshResult as { accessToken?: unknown }).accessToken === "string"
+  ) {
+    const refreshed = refreshResult as { accessToken: string; refreshToken?: string };
+    payload.accessToken = refreshed.accessToken;
+    if (typeof refreshed.refreshToken === "string" && refreshed.refreshToken) {
+      payload.refreshToken = refreshed.refreshToken;
+    }
+  }
+
+  // `refreshResult === null` (transient error already logged inside
+  // refreshCodexToken) is inconclusive — fall through and import the
+  // originally-supplied tokens rather than blocking on a network hiccup.
+  return null;
+}
 
 /**
  * POST /api/oauth/codex/import
@@ -78,6 +135,14 @@ export async function POST(request: Request) {
       results.push({ index: i, ok: false, error: norm.error });
       continue;
     }
+
+    const refreshError = await validateCodexRefreshToken(norm.payload);
+    if (refreshError) {
+      failed += 1;
+      results.push({ index: i, ok: false, error: refreshError });
+      continue;
+    }
+
     try {
       const conn = await createProviderConnection(norm.payload as Record<string, unknown>);
       imported += 1;
diff --git a/tests/unit/codex-import-refresh-validation-7522.test.ts b/tests/unit/codex-import-refresh-validation-7522.test.ts
new file mode 100644
index 0000000000..cb22a60748
--- /dev/null
+++ b/tests/unit/codex-import-refresh-validation-7522.test.ts
@@ -0,0 +1,172 @@
+// Regression test for #7522: POST /api/oauth/codex/import must validate the
+// imported refresh_token BEFORE persisting a connection. Previously a payload
+// carrying an already-invalidated refresh_token (e.g. `refresh_token_invalidated`
+// / a dead-on-arrival `auth.json`) was imported as `active` and only failed
+// confusingly on first real use.
+//
+// This test mocks global.fetch so `refreshCodexToken()` (open-sse/services/
+// tokenRefresh.ts) talks to a fake OpenAI OAuth token endpoint instead of the
+// network — the refresh exchange itself is reused, not reimplemented.
+//
+// DB handles are released in test.after (CLAUDE.md learning: unreleased
+// SQLite handles hang node:test).
+
+import test from "node:test";
+import assert from "node:assert/strict";
+import fs from "node:fs";
+import os from "node:os";
+import path from "node:path";
+
+const TEST_DATA_DIR = fs.mkdtempSync(path.join(os.tmpdir(), "omniroute-codex-import-refresh-"));
+process.env.DATA_DIR = TEST_DATA_DIR;
+
+const core = await import("../../src/lib/db/core.ts");
+const settingsDb = await import("../../src/lib/db/settings.ts");
+const providersDb = await import("../../src/lib/db/providers.ts");
+const route = await import("../../src/app/api/oauth/codex/import/route.ts");
+
+test.before(async () => {
+  await settingsDb.updateSettings({ requireLogin: false });
+});
+
+test.after(async () => {
+  core.resetDbInstance();
+  fs.rmSync(TEST_DATA_DIR, { recursive: true, force: true });
+});
+
+function jsonResponse(body: unknown, status = 200) {
+  return new Response(JSON.stringify(body), {
+    status,
+    headers: { "content-type": "application/json" },
+  });
+}
+
+async function withMockedFetch<T>(impl: typeof fetch, fn: () => Promise<T>): Promise<T> {
+  const original = globalThis.fetch;
+  globalThis.fetch = impl;
+  try {
+    return await fn();
+  } finally {
+    globalThis.fetch = original;
+  }
+}
+
+async function postImport(body: unknown) {
+  const request = new Request("http://localhost:20128/api/oauth/codex/import", {
+    method: "POST",
+    headers: { "Content-Type": "application/json" },
+    body: JSON.stringify(body),
+  });
+  const response = await route.POST(request);
+  return { status: response.status, body: await response.json() };
+}
+
+const BASE_RECORD = {
+  access_token: "seed-access-token",
+  refresh_token: "seed-refresh-token-2026-07-10",
+  email: "operator@example.com",
+};
+
+test("import: rejects a record whose refresh_token is already invalidated upstream (#7522)", async () => {
+  await withMockedFetch(
+    (async () =>
+      jsonResponse({ error: { code: "refresh_token_invalidated" } }, 401)) as unknown as typeof fetch,
+    async () => {
+      const { status, body } = await postImport({ accounts: BASE_RECORD });
+
+      assert.equal(status, 200);
+      assert.equal(body.success, false);
+      assert.equal(body.imported, 0);
+      assert.equal(body.failed, 1);
+      assert.equal(body.results[0].ok, false);
+      assert.match(body.results[0].error, /expired|codex login/i);
+
+      const rows = await providersDb.getProviderConnections({ provider: "codex" });
+      const created = rows.find((r) => r.email === BASE_RECORD.email);
+      assert.equal(created, undefined, "no connection should be persisted for a dead refresh_token");
+    }
+  );
+});
+
+test("import: rejects a record whose refresh_token was already consumed (refresh_token_reused)", async () => {
+  await withMockedFetch(
+    (async () =>
+      jsonResponse({ error: { code: "refresh_token_reused" } }, 400)) as unknown as typeof fetch,
+    async () => {
+      const { status, body } = await postImport({
+        accounts: { ...BASE_RECORD, email: "reused@example.com" },
+      });
+
+      assert.equal(status, 200);
+      assert.equal(body.success, false);
+      assert.equal(body.failed, 1);
+
+      const rows = await providersDb.getProviderConnections({ provider: "codex" });
+      const created = rows.find((r) => r.email === "reused@example.com");
+      assert.equal(created, undefined);
+    }
+  );
+});
+
+test("import: creates the connection (with rotated tokens) when the refresh_token is still valid", async () => {
+  await withMockedFetch(
+    (async () =>
+      jsonResponse({
+        access_token: "rotated-access-token",
+        refresh_token: "rotated-refresh-token",
+        expires_in: 3600,
+      })) as unknown as typeof fetch,
+    async () => {
+      const { status, body } = await postImport({
+        accounts: { ...BASE_RECORD, email: "valid@example.com" },
+      });
+
+      assert.equal(status, 200);
+      assert.equal(body.success, true);
+      assert.equal(body.imported, 1);
+      assert.equal(body.failed, 0);
+      assert.equal(body.results[0].ok, true);
+
+      const rows = await providersDb.getProviderConnections({ provider: "codex" });
+      const created = rows.find((r) => r.email === "valid@example.com");
+      assert.ok(created, "connection should be persisted for a valid refresh_token");
+      assert.equal(created?.accessToken, "rotated-access-token");
+      assert.equal(created?.refreshToken, "rotated-refresh-token");
+    }
+  );
+});
+
+test("import: a transient network error validating the refresh_token does not block the import", async () => {
+  await withMockedFetch(
+    (async () => {
+      throw new Error("ECONNRESET");
+    }) as unknown as typeof fetch,
+    async () => {
+      const { status, body } = await postImport({
+        accounts: { ...BASE_RECORD, email: "transient@example.com" },
+      });
+
+      assert.equal(status, 200);
+      assert.equal(body.success, true);
+      assert.equal(body.imported, 1);
+
+      const rows = await providersDb.getProviderConnections({ provider: "codex" });
+      const created = rows.find((r) => r.email === "transient@example.com");
+      assert.ok(created, "import should proceed with the original tokens on a transient failure");
+      assert.equal(created?.accessToken, BASE_RECORD.access_token);
+    }
+  );
+});
+
+test("import: error responses never leak a stack trace", async () => {
+  await withMockedFetch(
+    (async () => jsonResponse({ error: { code: "refresh_token_invalidated" } }, 401)) as unknown as typeof fetch,
+    async () => {
+      const { body } = await postImport({
+        accounts: { ...BASE_RECORD, email: "leak-check@example.com" },
+      });
+      assert.ok(!JSON.stringify(body).includes("at /"), "must not leak a stack trace");
+      assert.ok(!JSON.stringify(body).includes(".ts:"), "must not leak a source location");
+    }
+  );
+});