diff --git a/hermes_cli/auth_oauth_grants.py b/hermes_cli/auth_oauth_grants.py
index 59208ed2ad..1ccfd5b5db 100644
--- a/hermes_cli/auth_oauth_grants.py
+++ b/hermes_cli/auth_oauth_grants.py
@@ -30,7 +30,15 @@ SINGLE_USE_REFRESH_POOL_PROVIDERS = frozenset({"anthropic", "openai-codex", "xai
 SINGLE_USE_OAUTH_SINGLETON_FILES = (".anthropic_oauth.json",)
 
 # Providers whose device-code grants live under ``providers.<id>`` (not only the pool).
-_DEVICE_CODE_BLOCK_PROVIDERS = ("openai-codex", "xai-oauth")
+# Only a block carrying a refresh token is a forkable grant: an agent_key-only ``nous`` block is
+# not single-use and must survive.
+_DEVICE_CODE_BLOCK_PROVIDERS = ("openai-codex", "xai-oauth", "nous")
+
+
+def _block_tokens(block: Dict[str, Any]) -> Dict[str, Any]:
+    # Codex/xAI nest the pair under ``tokens``; Nous stores it flat on the block.
+    tokens = block.get("tokens")
+    return tokens if isinstance(tokens, dict) else block
 
 
 def _is_oauth_pool_payload(entry: Any) -> bool:
@@ -113,7 +121,7 @@ def strip_cloned_single_use_oauth_grants(profile_dir: Path) -> Dict[str, Any]:
         # profile working while removing the fork.
         for provider_id in _DEVICE_CODE_BLOCK_PROVIDERS:
             block = providers.get(provider_id)
-            if isinstance(block, dict) and block:
+            if isinstance(block, dict) and _block_tokens(block).get("refresh_token"):
                 del providers[provider_id]
                 stripped["providers"].append(provider_id)
                 changed = True
@@ -361,12 +369,12 @@ def _heal_forked_provider_block(
     if not (isinstance(p_providers, dict) and isinstance(r_providers, dict)):
         return None
     p_block, r_block = p_providers.get(provider_id), r_providers.get(provider_id)
-    if not (isinstance(p_block, dict) and p_block and isinstance(r_block, dict) and r_block):
+    if not (isinstance(p_block, dict) and _block_tokens(p_block).get("refresh_token")
+            and isinstance(r_block, dict) and r_block):
         return None
 
     def _flat(block: Dict[str, Any]) -> Dict[str, Any]:
-        tokens = block.get("tokens") if isinstance(block.get("tokens"), dict) else {}
-        return {**tokens, "last_refresh": block.get("last_refresh")}
+        return {**_block_tokens(block), "last_refresh": block.get("last_refresh")}
 
     p_flat, r_flat = _flat(p_block), _flat(r_block)
     # Provider blocks have no stable pool-row ID. Without a shared token pair
diff --git a/tests/agent/test_credential_pool_profile_oauth_fork.py b/tests/agent/test_credential_pool_profile_oauth_fork.py
index 85b5c1b107..3797c5a15f 100644
--- a/tests/agent/test_credential_pool_profile_oauth_fork.py
+++ b/tests/agent/test_credential_pool_profile_oauth_fork.py
@@ -155,6 +155,23 @@ def test_strip_helper_drops_device_code_blocks_and_reports(tmp_path):
     assert "openai-codex" not in store["providers"] and "nous" in store["providers"]
 
 
+def test_strip_helper_drops_cloned_nous_refresh_grant(tmp_path):
+    """Nous refresh tokens rotate on use: a cloned pool row or providers block is a fork (#121649)."""
+    from hermes_cli.auth import strip_cloned_single_use_oauth_grants
+    pdir = tmp_path / "p"
+    pdir.mkdir()
+    grant = {"access_token": "AT1", "refresh_token": "RT1", "agent_key": "AK"}
+    (pdir / "auth.json").write_text(json.dumps({
+        "version": 1,
+        "providers": {"nous": dict(grant)},
+        "credential_pool": {"nous": [dict(grant, id="n", source="device_code", auth_type="oauth")]},
+    }))
+    summary = strip_cloned_single_use_oauth_grants(pdir)
+    store = json.loads((pdir / "auth.json").read_text())
+    assert (summary["pool"], summary["providers"]) == (["nous"], ["nous"])
+    assert "nous" not in store["credential_pool"] and "nous" not in store["providers"]
+
+
 def test_strip_helper_is_a_noop_without_credentials(tmp_path):
     from hermes_cli.auth import strip_cloned_single_use_oauth_grants
     assert strip_cloned_single_use_oauth_grants(tmp_path) == {"pool": [], "providers": [], "files": []}