fix(auth): memoize the valid-token fast path too, add memo tests

Follow-ups on the startup-burst memo:

- Populate the memo on the valid-token fast path as well. The startup
  burst usually finds a VALID token, and each check_fn call still paid
  two cross-process file locks + state reads to reach that return; the
  original memo only engaged after a refresh. The token has at least
  refresh_skew_seconds (>=120s) of life at that return, so a 5s memo can
  never serve an expired token.
- Clear the module-level memo in test_nous_portal_staging_allowlist's
  refresh-capture helper: with the fast-path populate, a token memoized
  by an earlier test would otherwise short-circuit the refresh these
  tests assert on (3 tests failed without this).
- Add dedicated memo behavior tests (TTL hit, TTL expiry, insecure
  bypass) — the original PR shipped none. Mutation-checked: all 3 fail
  against main's un-memoized function, pass on this branch.

hermes_cli/auth.py

@@ -5825,6 +5825,15 @@ def resolve_nous_access_token(
             if not _is_expiring(state.get("expires_at"), refresh_skew_seconds):
                 if merged_shared:
                     _save_provider_state_to_source(auth_store, "nous", state, state_source_path)
+                # Populate the memo on the valid-token fast path too: the
+                # startup burst usually finds a *valid* token, but each
+                # check_fn call still pays two cross-process file locks and
+                # state reads to reach this return. The token has at least
+                # refresh_skew_seconds (>= 120s) of life here, so a 5s memo
+                # can never serve an expired token.
+                if not insecure and ca_bundle is None:
+                    with _RESOLVE_TOKEN_CACHE_LOCK:
+                        _RESOLVE_TOKEN_CACHE = (time.monotonic(), access_token)
                 return access_token
 
             if not isinstance(refresh_token, str) or not refresh_token:

tests/hermes_cli/test_nous_portal_staging_allowlist.py

@@ -87,6 +87,11 @@ class TestResolveAccessTokenEnvOverrideWins:
     def _run_and_capture(self, monkeypatch, auth):
         seen_portal_urls = []
 
+        # The resolve memo is module-level state; clear it so each test's
+        # resolution actually exercises the refresh path instead of serving
+        # a token cached by a previous test.
+        monkeypatch.setattr(auth, "_RESOLVE_TOKEN_CACHE", None)
+
         def _fake_refresh(*, client, portal_base_url, client_id, refresh_token):
             seen_portal_urls.append(portal_base_url)
             return {

tests/hermes_cli/test_resolve_token_memo.py

@@ -0,0 +1,96 @@
+"""Tests for the resolve_nous_access_token startup-burst memo (PR #66016).
+
+The memo collapses the startup burst of managed-tool check_fn calls into a
+single expensive resolution: within the short TTL, repeat calls return the
+cached token without re-entering _provider_state_transaction (two
+cross-process file locks + state reads) or triggering a network refresh.
+"""
+
+import json
+import time
+
+import pytest
+
+import hermes_cli.auth as auth
+
+
+@pytest.fixture(autouse=True)
+def _fresh_memo(monkeypatch, tmp_path):
+    monkeypatch.setenv("HERMES_HOME", str(tmp_path))
+    monkeypatch.delenv("HERMES_PORTAL_BASE_URL", raising=False)
+    monkeypatch.delenv("NOUS_PORTAL_BASE_URL", raising=False)
+    monkeypatch.setattr(auth, "_RESOLVE_TOKEN_CACHE", None)
+    yield
+
+
+def _write_valid_auth_file(tmp_path, token="memo-token"):
+    (tmp_path / "auth.json").write_text(
+        json.dumps(
+            {
+                "version": 1,
+                "active_provider": "nous",
+                "providers": {
+                    "nous": {
+                        "access_token": token,
+                        "refresh_token": "r",
+                        "client_id": "hermes-cli-vps",
+                        "expires_at": time.strftime(
+                            "%Y-%m-%dT%H:%M:%S+00:00", time.gmtime(time.time() + 3600)
+                        ),
+                    }
+                },
+            }
+        )
+    )
+
+
+def _count_transactions(monkeypatch):
+    calls = {"n": 0}
+    real = auth._provider_state_transaction
+
+    def _counting(provider):
+        calls["n"] += 1
+        return real(provider)
+
+    monkeypatch.setattr(auth, "_provider_state_transaction", _counting)
+    return calls
+
+
+def test_repeat_calls_within_ttl_hit_memo(monkeypatch, tmp_path):
+    _write_valid_auth_file(tmp_path)
+    calls = _count_transactions(monkeypatch)
+
+    first = auth.resolve_nous_access_token()
+    second = auth.resolve_nous_access_token()
+    third = auth.resolve_nous_access_token()
+
+    assert first == second == third == "memo-token"
+    assert calls["n"] == 1, (
+        "repeat calls within the TTL must not re-enter the state transaction"
+    )
+
+
+def test_memo_expires_after_ttl(monkeypatch, tmp_path):
+    _write_valid_auth_file(tmp_path)
+    calls = _count_transactions(monkeypatch)
+
+    auth.resolve_nous_access_token()
+    cached_at, tok = auth._RESOLVE_TOKEN_CACHE
+    monkeypatch.setattr(
+        auth,
+        "_RESOLVE_TOKEN_CACHE",
+        (cached_at - auth._RESOLVE_TOKEN_CACHE_TTL_S - 1.0, tok),
+    )
+    auth.resolve_nous_access_token()
+
+    assert calls["n"] == 2, "an expired memo must re-resolve"
+
+
+def test_insecure_callers_bypass_memo(monkeypatch, tmp_path):
+    _write_valid_auth_file(tmp_path)
+    calls = _count_transactions(monkeypatch)
+
+    auth.resolve_nous_access_token()
+    auth.resolve_nous_access_token(insecure=True)
+
+    assert calls["n"] == 2, "insecure callers must bypass the memo entirely"