diff --git a/agent/credential_pool.py b/agent/credential_pool.py
index 004b5749..27a16bd4 100644
--- a/agent/credential_pool.py
+++ b/agent/credential_pool.py
@@ -3,6 +3,7 @@
 from __future__ import annotations
 
 import logging
+import os
 import random
 import threading
 import time
@@ -13,7 +14,7 @@ from datetime import datetime
 from typing import Any, Dict, List, Optional, Set, Tuple
 
 from hermes_constants import OPENROUTER_BASE_URL
-from hermes_cli.config import get_env_value
+from hermes_cli.config import get_env_value, load_env
 import hermes_cli.auth as auth_mod
 from hermes_cli.auth import (
     CODEX_ACCESS_TOKEN_REFRESH_SKEW_SECONDS,
@@ -1380,6 +1381,16 @@ def _seed_from_singletons(provider: str, entries: List[PooledCredential]) -> Tup
 def _seed_from_env(provider: str, entries: List[PooledCredential]) -> Tuple[bool, Set[str]]:
     changed = False
     active_sources: Set[str] = set()
+
+    # Prefer ~/.hermes/.env over os.environ — the user's config file is the
+    # authoritative source for Hermes credentials. Stale env vars from parent
+    # processes (Codex CLI, test scripts, etc.) should not override deliberate
+    # changes to the .env file.
+    def _get_env_prefer_dotenv(key: str) -> str:
+        env_file = load_env()
+        val = env_file.get(key) or os.environ.get(key) or ""
+        return val.strip()
+
     # Honour user suppression — `hermes auth remove <provider> <N>` for an
     # env-seeded credential marks the env:<VAR> source as suppressed so it
     # won't be re-seeded from the user's shell environment or ~/.hermes/.env.
@@ -1391,8 +1402,8 @@ def _seed_from_env(provider: str, entries: List[PooledCredential]) -> Tuple[bool
         def _is_source_suppressed(_p, _s):  # type: ignore[misc]
             return False
     if provider == "openrouter":
-        # Check both os.environ and ~/.hermes/.env file
-        token = (get_env_value("OPENROUTER_API_KEY") or "").strip()
+        # Prefer ~/.hermes/.env over os.environ
+        token = _get_env_prefer_dotenv("OPENROUTER_API_KEY")
         if token:
             source = "env:OPENROUTER_API_KEY"
             if _is_source_suppressed(provider, source):
@@ -1418,7 +1429,7 @@ def _seed_from_env(provider: str, entries: List[PooledCredential]) -> Tuple[bool
 
     env_url = ""
     if pconfig.base_url_env_var:
-        env_url = (get_env_value(pconfig.base_url_env_var) or "").strip().rstrip("/")
+        env_url = _get_env_prefer_dotenv(pconfig.base_url_env_var).rstrip("/")
 
     env_vars = list(pconfig.api_key_env_vars)
     if provider == "anthropic":
@@ -1429,8 +1440,8 @@ def _seed_from_env(provider: str, entries: List[PooledCredential]) -> Tuple[bool
         ]
 
     for env_var in env_vars:
-        # Check both os.environ and ~/.hermes/.env file
-        token = (get_env_value(env_var) or "").strip()
+        # Prefer ~/.hermes/.env over os.environ
+        token = _get_env_prefer_dotenv(env_var)
         if not token:
             continue
         source = f"env:{env_var}"