diff --git a/hermes_cli/auth.py b/hermes_cli/auth.py
index 52bdf646fbc93..80a57a361ff2f 100644
--- a/hermes_cli/auth.py
+++ b/hermes_cli/auth.py
@@ -1715,11 +1715,29 @@ def write_credential_pool(
 
 
 def suppress_credential_source(provider_id: str, source: str) -> None:
-    """Mark a credential source as suppressed so it won't be re-seeded."""
+    """Mark a credential source as suppressed so it won't be re-seeded.
+
+    Older auth stores may represent a provider's suppressed sources as a
+    mapping.  Treat its keys as source names and migrate the value to the
+    canonical list form before appending the requested source.
+    """
     with _auth_store_lock():
         auth_store = _load_auth_store()
-        suppressed = auth_store.setdefault("suppressed_sources", {})
-        provider_list = suppressed.setdefault(provider_id, [])
+        suppressed = auth_store.get("suppressed_sources")
+        if not isinstance(suppressed, dict):
+            suppressed = {}
+            auth_store["suppressed_sources"] = suppressed
+
+        raw_sources = suppressed.get(provider_id)
+        if isinstance(raw_sources, list):
+            provider_list = raw_sources
+        elif isinstance(raw_sources, dict):
+            provider_list = [str(name) for name in raw_sources]
+            suppressed[provider_id] = provider_list
+        else:
+            provider_list = []
+            suppressed[provider_id] = provider_list
+
         if source not in provider_list:
             provider_list.append(source)
         _save_auth_store(auth_store)
@@ -1745,8 +1763,15 @@ def unsuppress_credential_source(provider_id: str, source: str) -> bool:
         suppressed = auth_store.get("suppressed_sources")
         if not isinstance(suppressed, dict):
             return False
-        provider_list = suppressed.get(provider_id)
-        if not isinstance(provider_list, list) or source not in provider_list:
+        raw_sources = suppressed.get(provider_id)
+        if isinstance(raw_sources, dict):
+            provider_list = [str(name) for name in raw_sources]
+            suppressed[provider_id] = provider_list
+        elif isinstance(raw_sources, list):
+            provider_list = raw_sources
+        else:
+            return False
+        if source not in provider_list:
             return False
         provider_list.remove(source)
         if not provider_list:
diff --git a/tests/agent/test_anthropic_output_field_leak.py b/tests/agent/test_anthropic_output_field_leak.py
index 93c05c3e62299..138aba2c0ef38 100644
--- a/tests/agent/test_anthropic_output_field_leak.py
+++ b/tests/agent/test_anthropic_output_field_leak.py
@@ -10,9 +10,6 @@
 normalize_response capture, _sanitize_replay_block (ordered-blocks replay), and
 _convert_content_part_to_anthropic (content-list replay).
 """
-import sys, os
-sys.path.insert(0, os.path.expanduser("~/.hermes/hermes-agent"))
-
 import pytest
 from agent.anthropic_adapter import (
     _sanitize_replay_block,
diff --git a/tests/hermes_cli/test_auth_commands.py b/tests/hermes_cli/test_auth_commands.py
index 3da85849c0448..f0a1010fb72a5 100644
--- a/tests/hermes_cli/test_auth_commands.py
+++ b/tests/hermes_cli/test_auth_commands.py
@@ -521,6 +521,40 @@ class _Args:
     assert entries[0]["priority"] == 0
 
 
+def test_auth_remove_codex_migrates_legacy_dict_suppression(tmp_path, monkeypatch):
+    """Removing a Codex credential must tolerate legacy dict suppression data."""
+    monkeypatch.setenv("HERMES_HOME", str(tmp_path / "hermes"))
+    store = _codex_pool_only_store()
+    primary = store["credential_pool"]["openai-codex"][0]
+    primary.update({"id": "codex-qb", "label": "qb"})
+    store["suppressed_sources"] = {"openai-codex": {"legacy": True}}
+    _write_auth_store(tmp_path, store)
+
+    from hermes_cli.auth_commands import auth_remove_command
+
+    class _Args:
+        provider = "openai-codex"
+        target = "qb"
+
+    auth_remove_command(_Args())
+
+    payload = json.loads((tmp_path / "hermes" / "auth.json").read_text(encoding="utf-8"))
+    assert payload.get("credential_pool", {}).get("openai-codex", []) == []
+    assert payload["suppressed_sources"]["openai-codex"] == [
+        "legacy",
+        "device_code",
+        "manual:device_code",
+    ]
+
+    from hermes_cli.auth import unsuppress_credential_source
+
+    assert unsuppress_credential_source("openai-codex", "legacy") is True
+
+    from agent.credential_pool import load_pool
+
+    assert load_pool("openai-codex").peek() is None
+
+
 def test_clear_provider_auth_removes_provider_pool_entries(tmp_path, monkeypatch):
     monkeypatch.setenv("HERMES_HOME", str(tmp_path / "hermes"))
     _write_auth_store(