diff --git a/agent/account_usage.py b/agent/account_usage.py
index b6de6e65bb..564b74572c 100644
--- a/agent/account_usage.py
+++ b/agent/account_usage.py
@@ -8,7 +8,7 @@ from typing import TYPE_CHECKING, Any, Callable, Optional
 
 import httpx
 
-from agent.anthropic_adapter import _is_oauth_token, resolve_anthropic_token
+from agent.anthropic_credentials import _is_oauth_token, resolve_anthropic_token
 from hermes_cli.auth import AuthError, _read_codex_tokens, resolve_codex_runtime_credentials
 from hermes_cli.runtime_provider import resolve_runtime_provider
 
diff --git a/agent/agent_init.py b/agent/agent_init.py
index a0158d4305..a12099a431 100644
--- a/agent/agent_init.py
+++ b/agent/agent_init.py
@@ -723,7 +723,8 @@ def _print_key_banner(key, label: str, warn_missing: bool = False) -> None:
 
 def _init_anthropic_client(agent, api_key, base_url, _provider_timeout):
     """anthropic_messages: native Anthropic SDK (or AnthropicBedrock for Bedrock+Claude)."""
-    from agent.anthropic_adapter import build_anthropic_client, resolve_anthropic_token
+    from agent.anthropic_adapter import build_anthropic_client
+    from agent.anthropic_credentials import resolve_anthropic_token
     agent.client = None
     agent._client_kwargs = {}
     agent._anthropic_base_url = base_url
@@ -766,7 +767,7 @@ def _init_anthropic_client(agent, api_key, base_url, _provider_timeout):
     # Third-party providers (MiniMax, Kimi, GLM, LiteLLM proxies) that accept the Anthropic protocol must
     # never trip OAuth code paths — doing so injects Claude-Code identity headers and system prompts that
     # cause 401/403 on their endpoints. See #1739.
-    from agent.anthropic_adapter import _is_oauth_token as _is_oat
+    from agent.anthropic_credentials import _is_oauth_token as _is_oat
     agent._is_anthropic_oauth = _is_oat(effective_key) if (_is_native_anthropic and isinstance(effective_key, str)) else False
     agent._anthropic_client = build_anthropic_client(effective_key, base_url, timeout=_provider_timeout)
     if not agent.quiet_mode:
diff --git a/agent/agent_runtime_helpers.py b/agent/agent_runtime_helpers.py
index e5d6e9c52a..8df9c243f4 100644
--- a/agent/agent_runtime_helpers.py
+++ b/agent/agent_runtime_helpers.py
@@ -1499,7 +1499,7 @@ def anthropic_prompt_cache_policy(
     # 64K-token prompts and re-billing the full prompt on every turn. Observed within-turn progression with
     # cache enabled: 1% → 67% → 84% → 97% (#25970). Reuses the canonical family matcher (covers bare
     # k1./k2./k25 release slugs the substring check missed).
-    from agent.anthropic_adapter import _model_name_is_kimi_family
+    from agent.anthropic_endpoints import _model_name_is_kimi_family
     is_kimi = _model_name_is_kimi_family(eff_model) or "moonshot" in model_lower
     is_openrouter = base_url_host_matches(eff_base_url, "openrouter.ai")
     # Nous Portal proxies to OpenRouter; treat as OpenRouter-equivalent for cache layout.
@@ -1859,7 +1859,8 @@ def _build_switched_client(agent, new_provider, api_key, base_url, api_mode, new
         agent.client = build_moa_facade(agent, agent.model)
         return
     if api_mode == "anthropic_messages":
-        from agent.anthropic_adapter import build_anthropic_client, resolve_anthropic_token, _is_oauth_token
+        from agent.anthropic_adapter import build_anthropic_client
+        from agent.anthropic_credentials import resolve_anthropic_token, _is_oauth_token
         # Only fall back to ANTHROPIC_TOKEN for native Anthropic; other anthropic_messages providers
         # must never receive Anthropic credentials.
         is_native_anthropic = new_provider == "anthropic"
diff --git a/agent/anthropic_adapter.py b/agent/anthropic_adapter.py
index cd21338fa5..4db2e2ea9b 100644
--- a/agent/anthropic_adapter.py
+++ b/agent/anthropic_adapter.py
@@ -2,38 +2,26 @@
 OpenAI-style internals. Auth: API keys (``sk-ant-api*``) -> x-api-key; OAuth setup-tokens
 (``sk-ant-oat*``) and Claude Code credentials -> Bearer + beta header. Endpoint predicates,
 payload conversion and credentials live in ``agent/anthropic_{endpoints,message_convert,
-credentials}.py`` and are re-exported here for long-standing imports."""
+credentials}.py``; import them from there."""
 
 import logging
 import math
 import re
 import subprocess
 from contextlib import suppress
-from pathlib import Path  # noqa: F401  (tests patch ``anthropic_adapter.Path.home``)
 from typing import Any, Dict, List, Optional
 
 from utils import normalize_proxy_env_vars
 
-from agent.anthropic_endpoints import (  # noqa: F401
+from agent.anthropic_credentials import _is_oauth_token
+from agent.anthropic_endpoints import (
     _base_url_needs_context_1m_beta, _is_azure_anthropic_endpoint, _is_kimi_coding_endpoint,
     _is_minimax_anthropic_endpoint, _is_nous_portal_endpoint, _is_opencode_endpoint,
     _is_third_party_anthropic_endpoint, _model_name_is_kimi_family, _normalize_base_url_text,
     _requires_bearer_auth,
 )
-from agent.anthropic_message_convert import (  # noqa: F401
-    _EMPTY_TEXT_PLACEHOLDER, _convert_assistant_message, _convert_content_part_to_anthropic,
-    _convert_user_message, _ensure_leading_user_turn, _is_bedrock_model_id, _safe_text,
-    _sanitize_replay_block, _scrub_blank_text_blocks, _to_plain_data, convert_messages_to_anthropic,
-    convert_tools_to_anthropic, normalize_model_name,
-)
-from agent.anthropic_credentials import (  # noqa: F401
-    _OAUTH_TOKEN_USER_AGENT, CredentialPersistError, _get_hermes_oauth_file, _getenv, _is_oauth_token,
-    _read_claude_code_credentials_from_keychain, _refresh_oauth_token, _resolve_anthropic_pool_token,
-    _resolve_claude_code_token_from_credentials, _write_claude_code_credentials,
-    _write_hermes_oauth_credentials, claude_code_credentials_path, is_claude_code_token_valid,
-    is_rotation_consumed_uncommitted, mark_rotation_consumed_uncommitted, read_claude_code_credentials,
-    read_hermes_oauth_credentials, refresh_anthropic_oauth_pure, resolve_anthropic_token,
-    run_hermes_oauth_login_pure, run_oauth_setup_token,
+from agent.anthropic_message_convert import (
+    convert_messages_to_anthropic, convert_tools_to_anthropic, normalize_model_name,
 )
 
 from hermes_cli import __version__ as _HERMES_VERSION
diff --git a/agent/anthropic_credentials.py b/agent/anthropic_credentials.py
index 5dcf3eab38..ed3f57f0ac 100644
--- a/agent/anthropic_credentials.py
+++ b/agent/anthropic_credentials.py
@@ -5,8 +5,7 @@
 ``auth.json`` credential pool. ``~/.hermes/.anthropic_oauth.json`` (Hermes PKCE) and
 the Claude Code file are *singletons*: ``credential_pool._seed_from_singletons()``
 re-reads them on every ``load_pool()``, so a failed write here is a failed refresh
-(``CredentialPersistError``), not a cache miss. ``agent.anthropic_adapter`` re-exports
-every public name below.
+(``CredentialPersistError``), not a cache miss.
 """
 
 import base64
@@ -33,11 +32,9 @@ logger = logging.getLogger(__name__)
 
 _OAUTH_CLIENT_ID = "9d1c250a-e61b-44d9-88ed-5944d1962f5e"
 # platform.claude.com is the live token host; console.anthropic.com 404s but is kept as a fallback.
-# _OAUTH_TOKEN_URL stays for backward-compatible imports.
 _OAUTH_TOKEN_URLS = [
     "https://platform.claude.com/v1/oauth/token", "https://console.anthropic.com/v1/oauth/token"
 ]
-_OAUTH_TOKEN_URL = _OAUTH_TOKEN_URLS[0]
 # Anthropic 429s token-endpoint requests whose UA starts with ``claude-code/`` (or Mozilla); the real CLI uses
 # bare axios there. Inference (build_anthropic_kwargs) still needs claude-code/.
 _OAUTH_TOKEN_USER_AGENT = "axios/1.7.9"
diff --git a/agent/anthropic_endpoints.py b/agent/anthropic_endpoints.py
index e261c1d34d..82b96c5af1 100644
--- a/agent/anthropic_endpoints.py
+++ b/agent/anthropic_endpoints.py
@@ -5,7 +5,7 @@ headers, and request quirks (MiniMax, Kimi/Moonshot, DeepSeek, OpenCode, Azure A
 Portal, Bedrock). Every such difference is decided from the configured base URL, so the
 predicates live together here as pure functions (no I/O, SDK or credentials) that both
 ``agent/anthropic_adapter.py`` and ``agent/anthropic_message_convert.py`` can import without a
-cycle. ``agent.anthropic_adapter`` re-exports every name below.
+cycle.
 """
 
 from urllib.parse import urlparse
diff --git a/agent/anthropic_message_convert.py b/agent/anthropic_message_convert.py
index cbfeb5c7cb..2335345ea7 100644
--- a/agent/anthropic_message_convert.py
+++ b/agent/anthropic_message_convert.py
@@ -2,7 +2,7 @@
 schemas, and the message list (content blocks, thinking blocks and their signatures,
 tool_use/tool_result pairing, cache_control placement, screenshot eviction, blank-block
 scrubbing). Endpoint predicates come from ``agent/anthropic_endpoints.py`` so this module never
-imports the adapter (no cycle); ``agent.anthropic_adapter`` re-exports the public names."""
+imports the adapter (no cycle)."""
 
 import copy
 import json
diff --git a/agent/auxiliary_client.py b/agent/auxiliary_client.py
index 9796ac8d8c..92e12a18e0 100644
--- a/agent/auxiliary_client.py
+++ b/agent/auxiliary_client.py
@@ -1600,7 +1600,7 @@ class _AnthropicCompletionsAdapter:
             candidate = str(getattr(real_client, "base_url", "") or "") or None
             if candidate:
                 with contextlib.suppress(Exception):
-                    from agent.anthropic_adapter import _is_nous_portal_endpoint
+                    from agent.anthropic_endpoints import _is_nous_portal_endpoint
                     if _is_nous_portal_endpoint(candidate):
                         self._base_url = candidate
 
@@ -2810,7 +2810,8 @@ def _try_azure_foundry(
 
 def _try_anthropic(explicit_api_key: str = None) -> Tuple[Optional[Any], Optional[str]]:
     try:
-        from agent.anthropic_adapter import build_anthropic_client, resolve_anthropic_token
+        from agent.anthropic_adapter import build_anthropic_client
+        from agent.anthropic_credentials import resolve_anthropic_token
     except ImportError:
         return None, None
     pool_present, entry = _select_pool_entry("anthropic")
@@ -2835,7 +2836,7 @@ def _try_anthropic(explicit_api_key: str = None) -> Tuple[Optional[Any], Optiona
                 cfg_base_url = (model_cfg.get("base_url") or "").strip().rstrip("/")
                 if cfg_base_url and _is_anthropic_compatible_host(cfg_base_url):
                     base_url = cfg_base_url
-    from agent.anthropic_adapter import _is_oauth_token
+    from agent.anthropic_credentials import _is_oauth_token
     is_oauth = _is_oauth_token(token)
     model = _get_aux_model_for_provider("anthropic") or "claude-haiku-4-5-20251001"
     if _aux_probe_active():
diff --git a/agent/chat_completion_helpers.py b/agent/chat_completion_helpers.py
index 6a1350082c..4fa0d7b545 100644
--- a/agent/chat_completion_helpers.py
+++ b/agent/chat_completion_helpers.py
@@ -1922,7 +1922,8 @@ def _swap_fallback_clients(agent, fb_client, fb_provider: str, fb_model: str, fb
     """Install the fallback client(s) in place, honoring request_timeout_seconds (None = SDK default)."""
     timeout = get_provider_request_timeout(fb_provider, fb_model)
     if fb_api_mode == "anthropic_messages":
-        from agent.anthropic_adapter import build_anthropic_client, resolve_anthropic_token, _is_oauth_token
+        from agent.anthropic_adapter import build_anthropic_client
+        from agent.anthropic_credentials import resolve_anthropic_token, _is_oauth_token
         is_anthropic = fb_provider == "anthropic"
         effective_key = fb_client.api_key or (resolve_anthropic_token() if is_anthropic else None) or ""
         agent.api_key = agent._anthropic_api_key = effective_key
diff --git a/agent/client_lifecycle.py b/agent/client_lifecycle.py
index 46b0d26448..a782654afe 100644
--- a/agent/client_lifecycle.py
+++ b/agent/client_lifecycle.py
@@ -420,7 +420,7 @@ class ClientLifecycleMixin:
 
     def _anthropic_oauth_flag(self, token: str) -> bool:
         """OAuth flag only on native Anthropic; third-party Anthropic-protocol endpoints must not trip OAuth paths."""
-        from agent.anthropic_adapter import _is_oauth_token
+        from agent.anthropic_credentials import _is_oauth_token
         return _is_oauth_token(token) if self.provider == "anthropic" else False
 
     def _build_anthropic_client_for_key(self, key: tuple) -> Any:
@@ -752,7 +752,7 @@ class ClientLifecycleMixin:
         ):
             return False
         try:
-            from agent.anthropic_adapter import resolve_anthropic_token
+            from agent.anthropic_credentials import resolve_anthropic_token
             new_token = resolve_anthropic_token()
         except Exception as exc:
             logger.debug("Anthropic credential refresh failed: %s", exc)
diff --git a/agent/transports/anthropic.py b/agent/transports/anthropic.py
index c80ad07099..978a0d4af2 100644
--- a/agent/transports/anthropic.py
+++ b/agent/transports/anthropic.py
@@ -44,12 +44,12 @@ class AnthropicTransport(ProviderTransport):
 
     def convert_messages(self, messages: List[Dict[str, Any]], **kwargs) -> Any:
         """Convert OpenAI messages to an Anthropic (system, messages) tuple; ``base_url`` affects thinking-signature handling."""
-        from agent.anthropic_adapter import convert_messages_to_anthropic
+        from agent.anthropic_message_convert import convert_messages_to_anthropic
         return convert_messages_to_anthropic(messages, base_url=kwargs.get("base_url"))
 
     def convert_tools(self, tools: List[Dict[str, Any]]) -> Any:
         """Convert OpenAI tool schemas to Anthropic input_schema format."""
-        from agent.anthropic_adapter import convert_tools_to_anthropic
+        from agent.anthropic_message_convert import convert_tools_to_anthropic
         return convert_tools_to_anthropic(tools)
 
     def build_kwargs(
@@ -65,7 +65,7 @@ class AnthropicTransport(ProviderTransport):
     def normalize_response(self, response: Any, **kwargs) -> NormalizedResponse:
         """Parse content blocks (text/thinking/tool_use), map stop_reason, collect reasoning_details."""
         import json
-        from agent.anthropic_adapter import _sanitize_replay_block, _to_plain_data
+        from agent.anthropic_message_convert import _sanitize_replay_block, _to_plain_data
         strip_tool_prefix = kwargs.get("strip_tool_prefix", False)
         text_parts, reasoning_parts, reasoning_details, tool_calls = [], [], [], []
         # Anthropic signs each thinking block against the blocks PRECEDING it; when thinking
diff --git a/hermes_cli/auth_commands.py b/hermes_cli/auth_commands.py
index 7b6b7f0cd1..a3c76ad564 100644
--- a/hermes_cli/auth_commands.py
+++ b/hermes_cli/auth_commands.py
@@ -179,7 +179,7 @@ def _format_exhausted_status(entry) -> str:
 
 
 def _anthropic_oauth_login(args) -> dict:
-    from agent import anthropic_adapter as anthropic_mod
+    from agent import anthropic_credentials as anthropic_mod
     creds = anthropic_mod.run_hermes_oauth_login_pure()
     if not creds:
         raise SystemExit("Anthropic OAuth login did not return credentials.")
diff --git a/hermes_cli/doctor_connectivity.py b/hermes_cli/doctor_connectivity.py
index 27ad855a0e..f5628c6b5c 100644
--- a/hermes_cli/doctor_connectivity.py
+++ b/hermes_cli/doctor_connectivity.py
@@ -154,7 +154,8 @@ def _probe_anthropic() -> ProbeResult:
         return _skip(name)
     try:
         import httpx
-        from agent.anthropic_adapter import _is_oauth_token, _COMMON_BETAS, _OAUTH_ONLY_BETAS, _CONTEXT_1M_BETA
+        from agent.anthropic_adapter import _COMMON_BETAS, _OAUTH_ONLY_BETAS, _CONTEXT_1M_BETA
+        from agent.anthropic_credentials import _is_oauth_token
         is_oauth = _is_oauth_token(key)
         headers = {"anthropic-version": "2023-06-01", **({"Authorization": f"Bearer {key}", "anthropic-beta": ",".join(_COMMON_BETAS + _OAUTH_ONLY_BETAS)}
                                                          if is_oauth else {"x-api-key": key})}
diff --git a/hermes_cli/inventory.py b/hermes_cli/inventory.py
index 9f910f8162..4102115891 100644
--- a/hermes_cli/inventory.py
+++ b/hermes_cli/inventory.py
@@ -439,7 +439,7 @@ def _anthropic_oauth_credentials_present() -> bool:
     """True when the user explicitly authenticated Anthropic via OAuth (Hermes device flow or Claude Code
     login) — those leave no trace in active_provider / model.provider / API-key env vars."""
     try:
-        from agent.anthropic_adapter import read_claude_code_credentials, read_hermes_oauth_credentials
+        from agent.anthropic_credentials import read_claude_code_credentials, read_hermes_oauth_credentials
 
         readers = (read_hermes_oauth_credentials, read_claude_code_credentials)
         if any((read() or {}).get("accessToken") for read in readers):
diff --git a/hermes_cli/main.py b/hermes_cli/main.py
index d113bc9143..918a3e0e6c 100644
--- a/hermes_cli/main.py
+++ b/hermes_cli/main.py
@@ -1164,10 +1164,7 @@ def _has_any_provider_configured(*, strict_profile_scope: bool = False) -> bool:
     # configured — having Claude Code installed isn't consent to use its tokens.
     if _has_hermes_config and not strict_profile_scope:
         try:
-            from agent.anthropic_adapter import (
-                read_claude_code_credentials,
-                is_claude_code_token_valid,
-            )
+            from agent.anthropic_credentials import read_claude_code_credentials, is_claude_code_token_valid
 
             creds = read_claude_code_credentials()
             if creds and (
diff --git a/hermes_cli/main_provider_setup.py b/hermes_cli/main_provider_setup.py
index 06ad533e51..c35bcb2f51 100644
--- a/hermes_cli/main_provider_setup.py
+++ b/hermes_cli/main_provider_setup.py
@@ -644,7 +644,7 @@ def _stepfun_base_url_for_region(region: str) -> str:
 
 def _run_anthropic_oauth_flow(save_env_value):
     """Run the Claude OAuth setup-token flow. Returns True if credentials were saved."""
-    from agent.anthropic_adapter import run_oauth_setup_token, read_claude_code_credentials, is_claude_code_token_valid
+    from agent.anthropic_credentials import run_oauth_setup_token, read_claude_code_credentials, is_claude_code_token_valid
     from hermes_cli.config import save_anthropic_oauth_token, use_anthropic_claude_code_credentials
 
     def _activate_claude_code_credentials_if_available() -> bool:
diff --git a/hermes_cli/model_setup_flows.py b/hermes_cli/model_setup_flows.py
index b065a652d1..c227aa7c12 100644
--- a/hermes_cli/model_setup_flows.py
+++ b/hermes_cli/model_setup_flows.py
@@ -999,7 +999,7 @@ def _model_flow_anthropic(config, current_model=""):
     existing_key = get_anthropic_key()
     cc_available = False
     with contextlib.suppress(Exception):
-        from agent.anthropic_adapter import read_claude_code_credentials, is_claude_code_token_valid, _is_oauth_token
+        from agent.anthropic_credentials import read_claude_code_credentials, is_claude_code_token_valid, _is_oauth_token
         cc_creds = read_claude_code_credentials()
         if cc_creds and is_claude_code_token_valid(cc_creds):
             cc_available = True
diff --git a/hermes_cli/model_switch_providers.py b/hermes_cli/model_switch_providers.py
index d673407546..72e3f3e036 100644
--- a/hermes_cli/model_switch_providers.py
+++ b/hermes_cli/model_switch_providers.py
@@ -747,7 +747,7 @@ def _overlay_has_creds(b: _PickerBuild, pid: str, hermes_slug: str, overlay) ->
         # The pool gates anthropic behind is_provider_explicitly_configured() (aux tasks must not
         # consume Claude Code tokens); the picker is discovery-oriented, so read the files directly.
         try:
-            from agent.anthropic_adapter import read_claude_code_credentials, read_hermes_oauth_credentials
+            from agent.anthropic_credentials import read_claude_code_credentials, read_hermes_oauth_credentials
             hermes_creds = read_hermes_oauth_credentials()
             cc_creds = read_claude_code_credentials()
             if (hermes_creds and hermes_creds.get("accessToken")) or (cc_creds and cc_creds.get("accessToken")):
diff --git a/hermes_cli/models.py b/hermes_cli/models.py
index 57a709eadf..dac18836e3 100644
--- a/hermes_cli/models.py
+++ b/hermes_cli/models.py
@@ -1668,7 +1668,7 @@ def _fetch_anthropic_models(
     ``api_key``, else ``resolve_anthropic_token()`` (env / OAuth / Claude Code), else a read-only
     API-key credential_pool entry."""
     try:
-        from agent.anthropic_adapter import resolve_anthropic_token, _is_oauth_token
+        from agent.anthropic_credentials import resolve_anthropic_token, _is_oauth_token
     except ImportError:
         return None
 
diff --git a/hermes_cli/runtime_provider.py b/hermes_cli/runtime_provider.py
index cc8c6e2ff7..d1807bdc2c 100644
--- a/hermes_cli/runtime_provider.py
+++ b/hermes_cli/runtime_provider.py
@@ -273,7 +273,7 @@ def _anthropic_cfg_base_url(model_cfg: Dict[str, Any]) -> str:
 
 
 def _anthropic_token_or_raise() -> str:
-    from agent.anthropic_adapter import resolve_anthropic_token
+    from agent.anthropic_credentials import resolve_anthropic_token
     token = resolve_anthropic_token()
     if not token:
         raise AuthError(_NO_ANTHROPIC_CREDENTIALS_MSG)
diff --git a/hermes_cli/web_routers/oauth.py b/hermes_cli/web_routers/oauth.py
index 3157b8f2b9..fb37c12fbf 100644
--- a/hermes_cli/web_routers/oauth.py
+++ b/hermes_cli/web_routers/oauth.py
@@ -528,7 +528,7 @@ def _clear_anthropic_auth() -> bool:
     """Clear only the Hermes-managed PKCE file and auth-store entry (never ~/.claude/*)."""
     cleared = False
     try:
-        from agent.anthropic_adapter import _get_hermes_oauth_file
+        from agent.anthropic_credentials import _get_hermes_oauth_file
         oauth_file = _get_hermes_oauth_file()
         if oauth_file.exists():
             oauth_file.unlink()
diff --git a/hermes_cli/web_server_oauth.py b/hermes_cli/web_server_oauth.py
index b4b83bb653..ceac055848 100644
--- a/hermes_cli/web_server_oauth.py
+++ b/hermes_cli/web_server_oauth.py
@@ -51,7 +51,7 @@ def _anthropic_oauth_status() -> Dict[str, Any]:
     ``claude-code`` entry, and counting it here would shadow a real ANTHROPIC_API_KEY.
     """
     try:
-        from agent.anthropic_adapter import read_hermes_oauth_credentials, _get_hermes_oauth_file
+        from agent.anthropic_credentials import read_hermes_oauth_credentials, _get_hermes_oauth_file
         hermes_creds = read_hermes_oauth_credentials()
     except Exception:
         hermes_creds = None
@@ -79,7 +79,7 @@ def _anthropic_oauth_status() -> Dict[str, Any]:
 def _claude_code_only_status() -> Dict[str, Any]:
     """Claude Code CLI credentials as their own entry, independent of the Anthropic card."""
     try:
-        from agent.anthropic_adapter import read_claude_code_credentials
+        from agent.anthropic_credentials import read_claude_code_credentials
         creds = read_claude_code_credentials()
     except Exception:
         creds = None
diff --git a/tests/agent/test_anthropic_adapter.py b/tests/agent/test_anthropic_adapter.py
index 61754a4307..3ded294a6c 100644
--- a/tests/agent/test_anthropic_adapter.py
+++ b/tests/agent/test_anthropic_adapter.py
@@ -9,23 +9,10 @@ from unittest.mock import patch, MagicMock
 import pytest
 
 from agent.prompt_caching import apply_anthropic_cache_control
-from agent.anthropic_adapter import (
-    _is_azure_anthropic_endpoint,
-    _is_oauth_token,
-    _refresh_oauth_token,
-    _to_plain_data,
-    _write_claude_code_credentials,
-    build_anthropic_client,
-    build_anthropic_bedrock_client,
-    build_anthropic_kwargs,
-    convert_messages_to_anthropic,
-    convert_tools_to_anthropic,
-    is_claude_code_token_valid,
-    normalize_model_name,
-    read_claude_code_credentials,
-    resolve_anthropic_token,
-    run_oauth_setup_token,
-)
+from agent.anthropic_adapter import build_anthropic_client, build_anthropic_bedrock_client, build_anthropic_kwargs
+from agent.anthropic_credentials import _is_oauth_token, _refresh_oauth_token, _write_claude_code_credentials, is_claude_code_token_valid, read_claude_code_credentials, resolve_anthropic_token, run_oauth_setup_token
+from agent.anthropic_endpoints import _is_azure_anthropic_endpoint
+from agent.anthropic_message_convert import _to_plain_data, convert_messages_to_anthropic, convert_tools_to_anthropic, normalize_model_name
 from agent.transports import get_transport
 
 
@@ -169,7 +156,7 @@ class TestReadClaudeCodeCredentials:
                 "expiresAt": int(time.time() * 1000) + 3600_000,
             }
         }))
-        monkeypatch.setattr("agent.anthropic_adapter.Path.home", lambda: tmp_path)
+        monkeypatch.setattr("agent.anthropic_credentials.Path.home", lambda: tmp_path)
         creds = read_claude_code_credentials()
         assert creds is not None
         assert creds["accessToken"] == "sk-ant-oat01-token"
@@ -179,7 +166,7 @@ class TestReadClaudeCodeCredentials:
     def test_ignores_primary_api_key_for_native_anthropic_resolution(self, tmp_path, monkeypatch):
         claude_json = tmp_path / ".claude.json"
         claude_json.write_text(json.dumps({"primaryApiKey": "sk-ant-api03-primary"}))
-        monkeypatch.setattr("agent.anthropic_adapter.Path.home", lambda: tmp_path)
+        monkeypatch.setattr("agent.anthropic_credentials.Path.home", lambda: tmp_path)
 
         creds = read_claude_code_credentials()
         assert creds is None
@@ -210,7 +197,7 @@ class TestResolveAnthropicToken:
         monkeypatch.setenv("ANTHROPIC_API_KEY", "sk-ant-api03-mykey")
         monkeypatch.setenv("ANTHROPIC_TOKEN", "sk-ant-oat01-mytoken")
         monkeypatch.delenv("CLAUDE_CODE_OAUTH_TOKEN", raising=False)
-        monkeypatch.setattr("agent.anthropic_adapter.Path.home", lambda: tmp_path)
+        monkeypatch.setattr("agent.anthropic_credentials.Path.home", lambda: tmp_path)
         assert resolve_anthropic_token() == "sk-ant-oat01-mytoken"
 
     def test_does_not_resolve_primary_api_key_as_native_anthropic_token(self, monkeypatch, tmp_path):
@@ -218,7 +205,7 @@ class TestResolveAnthropicToken:
         monkeypatch.delenv("ANTHROPIC_TOKEN", raising=False)
         monkeypatch.delenv("CLAUDE_CODE_OAUTH_TOKEN", raising=False)
         (tmp_path / ".claude.json").write_text(json.dumps({"primaryApiKey": "sk-ant-api03-primary"}))
-        monkeypatch.setattr("agent.anthropic_adapter.Path.home", lambda: tmp_path)
+        monkeypatch.setattr("agent.anthropic_credentials.Path.home", lambda: tmp_path)
 
         assert resolve_anthropic_token() is None
 
@@ -226,7 +213,7 @@ class TestResolveAnthropicToken:
         monkeypatch.setenv("ANTHROPIC_API_KEY", "sk-ant...ykey")
         monkeypatch.delenv("ANTHROPIC_TOKEN", raising=False)
         monkeypatch.delenv("CLAUDE_CODE_OAUTH_TOKEN", raising=False)
-        monkeypatch.setattr("agent.anthropic_adapter.Path.home", lambda: tmp_path)
+        monkeypatch.setattr("agent.anthropic_credentials.Path.home", lambda: tmp_path)
         assert resolve_anthropic_token() == "sk-ant...ykey"
 
     def test_api_key_wins_over_auto_discovered_claude_code_credentials(
@@ -244,7 +231,7 @@ class TestResolveAnthropicToken:
                 "expiresAt": int(time.time() * 1000) + 3600_000,
             }
         }))
-        monkeypatch.setattr("agent.anthropic_adapter.Path.home", lambda: tmp_path)
+        monkeypatch.setattr("agent.anthropic_credentials.Path.home", lambda: tmp_path)
 
         assert resolve_anthropic_token() == "sk-ant...ykey"
 
@@ -272,14 +259,14 @@ class TestResolveAnthropicToken:
                 "expiresAt": int(time.time() * 1000) + 3600_000,
             }
         }))
-        monkeypatch.setattr("agent.anthropic_adapter.Path.home", lambda: tmp_path)
+        monkeypatch.setattr("agent.anthropic_credentials.Path.home", lambda: tmp_path)
         assert resolve_anthropic_token() == "cc-auto-token"
 
     def test_falls_back_to_anthropic_credential_pool_oauth(self, monkeypatch, tmp_path):
         monkeypatch.delenv("ANTHROPIC_API_KEY", raising=False)
         monkeypatch.delenv("ANTHROPIC_TOKEN", raising=False)
         monkeypatch.delenv("CLAUDE_CODE_OAUTH_TOKEN", raising=False)
-        monkeypatch.setattr("agent.anthropic_adapter.Path.home", lambda: tmp_path)
+        monkeypatch.setattr("agent.anthropic_credentials.Path.home", lambda: tmp_path)
         # Isolate source #5 (credential_pool): ensure source #4 (Claude Code
         # creds, incl. the macOS keychain read which Path.home does not cover)
         # returns nothing, mirroring a Hermes-PKCE-only setup.
@@ -300,7 +287,7 @@ class TestResolveAnthropicToken:
         monkeypatch.setenv("ANTHROPIC_API_KEY", "sk-ant...ykey")
         monkeypatch.delenv("ANTHROPIC_TOKEN", raising=False)
         monkeypatch.delenv("CLAUDE_CODE_OAUTH_TOKEN", raising=False)
-        monkeypatch.setattr("agent.anthropic_adapter.Path.home", lambda: tmp_path)
+        monkeypatch.setattr("agent.anthropic_credentials.Path.home", lambda: tmp_path)
         monkeypatch.setattr(
             "agent.anthropic_credentials.read_claude_code_credentials",
             self._assert_not_called,
@@ -320,7 +307,7 @@ class TestResolveAnthropicToken:
         monkeypatch.setenv("ANTHROPIC_API_KEY", "sk-ant...ykey")
         monkeypatch.delenv("ANTHROPIC_TOKEN", raising=False)
         monkeypatch.delenv("CLAUDE_CODE_OAUTH_TOKEN", raising=False)
-        monkeypatch.setattr("agent.anthropic_adapter.Path.home", lambda: tmp_path)
+        monkeypatch.setattr("agent.anthropic_credentials.Path.home", lambda: tmp_path)
         monkeypatch.setattr("agent.anthropic_credentials.read_claude_code_credentials", lambda: None)
 
         broken_entry = SimpleNamespace(auth_type="oauth", access_token=None)
@@ -340,7 +327,7 @@ class TestResolveAnthropicToken:
         monkeypatch.delenv("ANTHROPIC_API_KEY", raising=False)
         monkeypatch.delenv("ANTHROPIC_TOKEN", raising=False)
         monkeypatch.delenv("CLAUDE_CODE_OAUTH_TOKEN", raising=False)
-        monkeypatch.setattr("agent.anthropic_adapter.Path.home", lambda: tmp_path)
+        monkeypatch.setattr("agent.anthropic_credentials.Path.home", lambda: tmp_path)
         monkeypatch.setattr("agent.anthropic_credentials.read_claude_code_credentials", lambda: None)
 
         api_key_entry = SimpleNamespace(auth_type="api_key", access_token="sk-pool-apikey")
@@ -360,7 +347,7 @@ class TestResolveAnthropicToken:
         monkeypatch.delenv("ANTHROPIC_API_KEY", raising=False)
         monkeypatch.delenv("ANTHROPIC_TOKEN", raising=False)
         monkeypatch.delenv("CLAUDE_CODE_OAUTH_TOKEN", raising=False)
-        monkeypatch.setattr("agent.anthropic_adapter.Path.home", lambda: tmp_path)
+        monkeypatch.setattr("agent.anthropic_credentials.Path.home", lambda: tmp_path)
         monkeypatch.setattr("agent.anthropic_credentials.read_claude_code_credentials", lambda: None)
 
         captured = {}
@@ -389,7 +376,7 @@ class TestResolveAnthropicToken:
                 "expiresAt": int(time.time() * 1000) + 3600_000,
             }
         }))
-        monkeypatch.setattr("agent.anthropic_adapter.Path.home", lambda: tmp_path)
+        monkeypatch.setattr("agent.anthropic_credentials.Path.home", lambda: tmp_path)
 
         assert resolve_anthropic_token() == "cc-auto-token"
 
@@ -397,7 +384,7 @@ class TestResolveAnthropicToken:
 
 class TestRefreshOauthToken:
     def test_returns_none_without_refresh_token(self, tmp_path, monkeypatch):
-        monkeypatch.setattr("agent.anthropic_adapter.Path.home", lambda: tmp_path)
+        monkeypatch.setattr("agent.anthropic_credentials.Path.home", lambda: tmp_path)
         # Neutralize live Claude Code sources (macOS Keychain + ~/.claude file)
         # so the adopt-already-refreshed branch can't short-circuit with a real
         # credential on a dev/CI machine that happens to have Claude Code creds.
@@ -408,7 +395,7 @@ class TestRefreshOauthToken:
         assert _refresh_oauth_token(creds) is None
 
     def test_successful_refresh(self, tmp_path, monkeypatch):
-        monkeypatch.setattr("agent.anthropic_adapter.Path.home", lambda: tmp_path)
+        monkeypatch.setattr("agent.anthropic_credentials.Path.home", lambda: tmp_path)
         monkeypatch.setattr(
             "agent.anthropic_credentials.read_claude_code_credentials", lambda: None
         )
@@ -444,7 +431,7 @@ class TestRefreshOauthToken:
         assert written["claudeAiOauth"]["refreshToken"] == "new-refresh-456"
 
     def test_failed_refresh_returns_none(self, tmp_path, monkeypatch):
-        monkeypatch.setattr("agent.anthropic_adapter.Path.home", lambda: tmp_path)
+        monkeypatch.setattr("agent.anthropic_credentials.Path.home", lambda: tmp_path)
         monkeypatch.setattr(
             "agent.anthropic_credentials.read_claude_code_credentials", lambda: None
         )
@@ -460,7 +447,7 @@ class TestRefreshOauthToken:
 
 class TestWriteClaudeCodeCredentials:
     def test_writes_new_file(self, tmp_path, monkeypatch):
-        monkeypatch.setattr("agent.anthropic_adapter.Path.home", lambda: tmp_path)
+        monkeypatch.setattr("agent.anthropic_credentials.Path.home", lambda: tmp_path)
         _write_claude_code_credentials("tok", "ref", 12345)
         cred_file = tmp_path / ".claude" / ".credentials.json"
         assert cred_file.exists()
@@ -470,7 +457,7 @@ class TestWriteClaudeCodeCredentials:
         assert data["claudeAiOauth"]["expiresAt"] == 12345
 
     def test_preserves_existing_fields(self, tmp_path, monkeypatch):
-        monkeypatch.setattr("agent.anthropic_adapter.Path.home", lambda: tmp_path)
+        monkeypatch.setattr("agent.anthropic_credentials.Path.home", lambda: tmp_path)
         cred_dir = tmp_path / ".claude"
         cred_dir.mkdir()
         cred_file = cred_dir / ".credentials.json"
@@ -490,7 +477,7 @@ class TestWriteClaudeCodeCredentials:
         the fix shipped in #19673 (google_oauth) and #21148 (mcp_oauth).
         """
         import stat as _stat
-        monkeypatch.setattr("agent.anthropic_adapter.Path.home", lambda: tmp_path)
+        monkeypatch.setattr("agent.anthropic_credentials.Path.home", lambda: tmp_path)
         _write_claude_code_credentials("tok", "ref", 12345)
 
         cred_file = tmp_path / ".claude" / ".credentials.json"
@@ -516,7 +503,7 @@ class TestResolveWithRefresh:
                 "expiresAt": int(time.time() * 1000) - 3600_000,
             }
         }))
-        monkeypatch.setattr("agent.anthropic_adapter.Path.home", lambda: tmp_path)
+        monkeypatch.setattr("agent.anthropic_credentials.Path.home", lambda: tmp_path)
 
         # Mock refresh to succeed
         with patch("agent.anthropic_credentials._refresh_oauth_token", return_value="refreshed-token"):
@@ -538,7 +525,7 @@ class TestResolveWithRefresh:
                 "expiresAt": int(time.time() * 1000) - 3600_000,
             }
         }))
-        monkeypatch.setattr("agent.anthropic_adapter.Path.home", lambda: tmp_path)
+        monkeypatch.setattr("agent.anthropic_credentials.Path.home", lambda: tmp_path)
 
         with patch("agent.anthropic_credentials._refresh_oauth_token", return_value="refreshed-token"):
             result = resolve_anthropic_token()
@@ -564,7 +551,7 @@ class TestRunOauthSetupToken:
                 "expiresAt": int(time.time() * 1000) + 3600_000,
             }
         }))
-        monkeypatch.setattr("agent.anthropic_adapter.Path.home", lambda: tmp_path)
+        monkeypatch.setattr("agent.anthropic_credentials.Path.home", lambda: tmp_path)
 
         with patch("subprocess.run") as mock_run:
             mock_run.return_value = MagicMock(returncode=0)
@@ -583,7 +570,7 @@ class TestRunOauthSetupToken:
         monkeypatch.setattr("shutil.which", lambda _: "/usr/bin/claude")
         monkeypatch.delenv("CLAUDE_CODE_OAUTH_TOKEN", raising=False)
         monkeypatch.delenv("ANTHROPIC_TOKEN", raising=False)
-        monkeypatch.setattr("agent.anthropic_adapter.Path.home", lambda: tmp_path)
+        monkeypatch.setattr("agent.anthropic_credentials.Path.home", lambda: tmp_path)
 
         with patch("subprocess.run") as mock_run:
             mock_run.return_value = MagicMock(returncode=0)
@@ -1053,10 +1040,8 @@ class TestBuildAnthropicKwargs:
         classified as Kimi family (adaptive thinking) even on proxied
         endpoints where only the model name is available. Lookalike
         non-Kimi names must NOT match the exact-slug rule."""
-        from agent.anthropic_adapter import (
-            _model_name_is_kimi_family,
-            _supports_adaptive_thinking,
-        )
+        from agent.anthropic_adapter import _supports_adaptive_thinking
+        from agent.anthropic_endpoints import _model_name_is_kimi_family
         for m in ("k3", "K3", "moonshotai/k3", "k3.1-preview", "k3-turbo"):
             assert _model_name_is_kimi_family(m) is True, m
         assert _supports_adaptive_thinking("k3") is True
@@ -1502,7 +1487,7 @@ class TestBlankTextBlockFiltering:
     """
 
     def _convert(self, message):
-        from agent.anthropic_adapter import _convert_assistant_message
+        from agent.anthropic_message_convert import _convert_assistant_message
         return _convert_assistant_message(message)
 
 
@@ -1563,7 +1548,7 @@ class TestBlankTextBlockFiltering:
         a blank text block carrying cache_control (e.g. a stored, previously
         cache-marked turn where prompt_caching later becomes blank on replay)
         must not silently lose the breakpoint when dropped."""
-        from agent.anthropic_adapter import _convert_assistant_message
+        from agent.anthropic_message_convert import _convert_assistant_message
         msg = {
             "role": "assistant",
             "content": "",
@@ -1604,7 +1589,7 @@ class TestAllBlankFallbackAndNonStringText:
     """
 
     def _convert(self, message):
-        from agent.anthropic_adapter import _convert_assistant_message
+        from agent.anthropic_message_convert import _convert_assistant_message
         return _convert_assistant_message(message)
 
 
@@ -1674,7 +1659,7 @@ class TestReplayAllBlankFallback:
     """
 
     def _convert(self, message):
-        from agent.anthropic_adapter import _convert_assistant_message
+        from agent.anthropic_message_convert import _convert_assistant_message
         return _convert_assistant_message(message)
 
     def test_sole_blank_marked_replay_block_keeps_marker_on_placeholder(self):
diff --git a/tests/agent/test_anthropic_keychain.py b/tests/agent/test_anthropic_keychain.py
index 7f1174967c..3b7cfffeca 100644
--- a/tests/agent/test_anthropic_keychain.py
+++ b/tests/agent/test_anthropic_keychain.py
@@ -7,11 +7,7 @@ from unittest.mock import patch, MagicMock
 
 import pytest
 
-from agent.anthropic_adapter import (
-    _read_claude_code_credentials_from_keychain,
-    read_claude_code_credentials,
-    _refresh_oauth_token,
-)
+from agent.anthropic_credentials import _read_claude_code_credentials_from_keychain, read_claude_code_credentials, _refresh_oauth_token
 
 
 # This module exercises the reader itself with explicit platform and subprocess
@@ -67,7 +63,7 @@ class TestReadClaudeCodeCredentialsPriority:
                 "expiresAt": 9999999999999,
             }
         }))
-        monkeypatch.setattr("agent.anthropic_adapter.Path.home", lambda: tmp_path)
+        monkeypatch.setattr("agent.anthropic_credentials.Path.home", lambda: tmp_path)
 
         # Mock Keychain to return a "newer" token
         with patch("agent.anthropic_adapter.subprocess.run") as mock_run:
@@ -100,7 +96,7 @@ class TestReadClaudeCodeCredentialsPriority:
                 "expiresAt": 9999999999999,
             }
         }))
-        monkeypatch.setattr("agent.anthropic_adapter.Path.home", lambda: tmp_path)
+        monkeypatch.setattr("agent.anthropic_credentials.Path.home", lambda: tmp_path)
 
         with patch("agent.anthropic_adapter.subprocess.run") as mock_run:
             # Simulate Keychain entry not found
@@ -113,7 +109,7 @@ class TestReadClaudeCodeCredentialsPriority:
 
     def test_returns_none_when_neither_keychain_nor_json_has_creds(self, tmp_path, monkeypatch):
         """No credentials anywhere — must return None cleanly."""
-        monkeypatch.setattr("agent.anthropic_adapter.Path.home", lambda: tmp_path)
+        monkeypatch.setattr("agent.anthropic_credentials.Path.home", lambda: tmp_path)
 
         with patch("agent.anthropic_adapter.subprocess.run") as mock_run:
             mock_run.return_value = MagicMock(returncode=1, stdout="", stderr="")
@@ -147,7 +143,7 @@ class TestReadClaudeCodeCredentialsDesync:
                 "expiresAt": file_expires_at,
             }
         }))
-        monkeypatch.setattr("agent.anthropic_adapter.Path.home", lambda: tmp_path)
+        monkeypatch.setattr("agent.anthropic_credentials.Path.home", lambda: tmp_path)
 
     def _keychain_payload(self, *, access_token, expires_at, refresh_token="kc-refresh"):
         return MagicMock(
diff --git a/tests/agent/test_anthropic_kimi_signed_thinking_replay.py b/tests/agent/test_anthropic_kimi_signed_thinking_replay.py
index efb3edabca..bd3058c409 100644
--- a/tests/agent/test_anthropic_kimi_signed_thinking_replay.py
+++ b/tests/agent/test_anthropic_kimi_signed_thinking_replay.py
@@ -3,7 +3,7 @@
 from types import SimpleNamespace
 
 from agent.transports import get_transport
-from agent.anthropic_adapter import convert_messages_to_anthropic
+from agent.anthropic_message_convert import convert_messages_to_anthropic
 
 SIG = "sig-k3"
 
diff --git a/tests/agent/test_anthropic_oauth_pkce.py b/tests/agent/test_anthropic_oauth_pkce.py
index 764623232c..3336317643 100644
--- a/tests/agent/test_anthropic_oauth_pkce.py
+++ b/tests/agent/test_anthropic_oauth_pkce.py
@@ -120,7 +120,7 @@ def test_authorization_url_state_is_not_pkce_verifier(monkeypatch, tmp_path):
 
     monkeypatch.setattr(builtins, "input", fake_input)
 
-    from agent.anthropic_adapter import run_hermes_oauth_login_pure
+    from agent.anthropic_credentials import run_hermes_oauth_login_pure
 
     result = run_hermes_oauth_login_pure()
     assert result is not None, "OAuth flow should succeed with matching state"
@@ -176,7 +176,7 @@ def test_login_token_exchange_uses_platform_claude_host(monkeypatch, tmp_path):
 
     monkeypatch.setattr(builtins, "input", fake_input)
 
-    from agent.anthropic_adapter import run_hermes_oauth_login_pure
+    from agent.anthropic_credentials import run_hermes_oauth_login_pure
 
     result = run_hermes_oauth_login_pure()
 
@@ -207,7 +207,7 @@ def test_callback_state_mismatch_aborts(monkeypatch, tmp_path, caplog):
         capture_token_request=captured_token,
     )
 
-    from agent.anthropic_adapter import run_hermes_oauth_login_pure
+    from agent.anthropic_credentials import run_hermes_oauth_login_pure
 
     result = run_hermes_oauth_login_pure()
 
diff --git a/tests/agent/test_anthropic_oauth_ua_prefix.py b/tests/agent/test_anthropic_oauth_ua_prefix.py
index 8f0ae90fa7..e5161afa2d 100644
--- a/tests/agent/test_anthropic_oauth_ua_prefix.py
+++ b/tests/agent/test_anthropic_oauth_ua_prefix.py
@@ -45,7 +45,7 @@ class TestOAuthUserAgentPrefix:
     def test_token_refresh_ua_not_throttled(self):
         """refresh_anthropic_oauth_pure must NOT send a throttled token-endpoint UA."""
         import inspect
-        import agent.anthropic_adapter as mod
+        import agent.anthropic_credentials as mod
 
         func = getattr(mod, "refresh_anthropic_oauth_pure", None)
         if func is None or not callable(func):
diff --git a/tests/agent/test_anthropic_output_field_leak.py b/tests/agent/test_anthropic_output_field_leak.py
index 138aba2c0e..d2b883c317 100644
--- a/tests/agent/test_anthropic_output_field_leak.py
+++ b/tests/agent/test_anthropic_output_field_leak.py
@@ -11,11 +11,7 @@ normalize_response capture, _sanitize_replay_block (ordered-blocks replay), and
 _convert_content_part_to_anthropic (content-list replay).
 """
 import pytest
-from agent.anthropic_adapter import (
-    _sanitize_replay_block,
-    _convert_content_part_to_anthropic,
-    _convert_assistant_message,
-)
+from agent.anthropic_message_convert import _sanitize_replay_block, _convert_content_part_to_anthropic, _convert_assistant_message
 
 FORBIDDEN = {"parsed_output", "caller"}
 
diff --git a/tests/agent/test_anthropic_request_blank_block_guard.py b/tests/agent/test_anthropic_request_blank_block_guard.py
index e253436911..cc8095a306 100644
--- a/tests/agent/test_anthropic_request_blank_block_guard.py
+++ b/tests/agent/test_anthropic_request_blank_block_guard.py
@@ -13,10 +13,7 @@ list, and the system-block path coerces blanks at extraction time (a blank block
 carrying a cache_control breakpoint cannot be dropped).
 Ref #69512 / #70909 (follow-up: request-level guard, not just per-message).
 """
-from agent.anthropic_adapter import (
-    _EMPTY_TEXT_PLACEHOLDER,
-    convert_messages_to_anthropic,
-)
+from agent.anthropic_message_convert import _EMPTY_TEXT_PLACEHOLDER, convert_messages_to_anthropic
 
 
 def _all_text_blocks(messages):
diff --git a/tests/agent/test_anthropic_thinking_block_order.py b/tests/agent/test_anthropic_thinking_block_order.py
index 5455b3339a..db73d46b80 100644
--- a/tests/agent/test_anthropic_thinking_block_order.py
+++ b/tests/agent/test_anthropic_thinking_block_order.py
@@ -36,7 +36,7 @@ from types import SimpleNamespace
 import pytest
 
 from agent.transports import get_transport
-from agent.anthropic_adapter import convert_messages_to_anthropic
+from agent.anthropic_message_convert import convert_messages_to_anthropic
 
 
 def _thinking_block(text: str, signature: str) -> SimpleNamespace:
diff --git a/tests/agent/test_anthropic_token_scope_isolation.py b/tests/agent/test_anthropic_token_scope_isolation.py
index 6f3a48c1ab..a435e3d74b 100644
--- a/tests/agent/test_anthropic_token_scope_isolation.py
+++ b/tests/agent/test_anthropic_token_scope_isolation.py
@@ -32,7 +32,7 @@ import pytest
 from unittest.mock import patch
 
 from agent import secret_scope as ss
-from agent.anthropic_adapter import resolve_anthropic_token
+from agent.anthropic_credentials import resolve_anthropic_token
 
 
 @pytest.fixture(autouse=True)
diff --git a/tests/agent/test_anthropic_whitespace_text_blocks.py b/tests/agent/test_anthropic_whitespace_text_blocks.py
index 4232240f05..9aac5aa111 100644
--- a/tests/agent/test_anthropic_whitespace_text_blocks.py
+++ b/tests/agent/test_anthropic_whitespace_text_blocks.py
@@ -12,12 +12,7 @@ text to a non-whitespace placeholder at two points on the Anthropic request path
 in ``_convert_assistant_message`` (main path). Ref #69512.
 """
 import pytest
-from agent.anthropic_adapter import (
-    _EMPTY_TEXT_PLACEHOLDER,
-    _safe_text,
-    _sanitize_replay_block,
-    _convert_assistant_message,
-)
+from agent.anthropic_message_convert import _EMPTY_TEXT_PLACEHOLDER, _safe_text, _sanitize_replay_block, _convert_assistant_message
 
 
 def _text_blocks(msg):
diff --git a/tests/agent/test_auxiliary_anthropic_pool_fallback_regression.py b/tests/agent/test_auxiliary_anthropic_pool_fallback_regression.py
index 6277bac5f1..e797765ef0 100644
--- a/tests/agent/test_auxiliary_anthropic_pool_fallback_regression.py
+++ b/tests/agent/test_auxiliary_anthropic_pool_fallback_regression.py
@@ -53,7 +53,7 @@ class TestAnthropicPoolExhaustedFallsBackToEnv:
         with patch(
             "agent.auxiliary_client._select_pool_entry", return_value=(True, None)
         ), patch(
-            "agent.anthropic_adapter.resolve_anthropic_token", return_value=None
+            "agent.anthropic_credentials.resolve_anthropic_token", return_value=None
         ):
             from agent.auxiliary_client import _try_anthropic
 
diff --git a/tests/agent/test_auxiliary_client.py b/tests/agent/test_auxiliary_client.py
index c0c485ea72..f2930a0604 100644
--- a/tests/agent/test_auxiliary_client.py
+++ b/tests/agent/test_auxiliary_client.py
@@ -670,7 +670,7 @@ class TestAnthropicOAuthFlag:
 
     def test_api_key_no_oauth_flag(self, monkeypatch):
         """Regular API keys (sk-ant-api-*) should create client with is_oauth=False."""
-        with patch("agent.anthropic_adapter.resolve_anthropic_token", return_value="sk-ant-api03-testkey1234"), \
+        with patch("agent.anthropic_credentials.resolve_anthropic_token", return_value="sk-ant-api03-testkey1234"), \
              patch("agent.anthropic_adapter.build_anthropic_client") as mock_build, \
              patch("agent.auxiliary_client._select_pool_entry", return_value=(False, None)):
             mock_build.return_value = MagicMock()
@@ -695,7 +695,7 @@ class TestAnthropicOAuthFlag:
 
         with (
             patch("agent.auxiliary_client.load_pool", return_value=_Pool()),
-            patch("agent.anthropic_adapter.resolve_anthropic_token", side_effect=AssertionError("legacy path should not run")),
+            patch("agent.anthropic_credentials.resolve_anthropic_token", side_effect=AssertionError("legacy path should not run")),
             patch("agent.anthropic_adapter.build_anthropic_client", return_value=MagicMock()) as mock_build,
         ):
             from agent.auxiliary_client import _try_anthropic
@@ -961,7 +961,7 @@ class TestExplicitProviderRouting:
 
     def test_explicit_anthropic_api_key(self, monkeypatch):
         """provider='anthropic' + regular API key should work with is_oauth=False."""
-        with patch("agent.anthropic_adapter.resolve_anthropic_token", return_value="sk-ant-api-regular-key"), \
+        with patch("agent.anthropic_credentials.resolve_anthropic_token", return_value="sk-ant-api-regular-key"), \
              patch("agent.anthropic_adapter.build_anthropic_client") as mock_build, \
              patch("agent.auxiliary_client._select_pool_entry", return_value=(False, None)):
             mock_build.return_value = MagicMock()
@@ -1217,7 +1217,7 @@ class TestVisionClientFallback:
             patch("agent.auxiliary_client._read_main_provider", return_value="anthropic"),
             patch("agent.auxiliary_client._read_main_model", return_value="claude-sonnet-4"),
             patch("agent.anthropic_adapter.build_anthropic_client", return_value=MagicMock()),
-            patch("agent.anthropic_adapter.resolve_anthropic_token", return_value="***"),
+            patch("agent.anthropic_credentials.resolve_anthropic_token", return_value="***"),
         ):
             backends = get_available_vision_backends()
 
@@ -4027,7 +4027,7 @@ class TestAnthropicExplicitApiKey:
 
     def test_try_anthropic_uses_explicit_api_key_over_env(self):
         """_try_anthropic(explicit_api_key) must use the supplied key, not the env fallback."""
-        with patch("agent.anthropic_adapter.resolve_anthropic_token", return_value="env-fallback-key"), \
+        with patch("agent.anthropic_credentials.resolve_anthropic_token", return_value="env-fallback-key"), \
              patch("agent.anthropic_adapter.build_anthropic_client") as mock_build, \
              patch("agent.auxiliary_client._select_pool_entry", return_value=(False, None)):
             mock_build.return_value = MagicMock()
@@ -4041,7 +4041,7 @@ class TestAnthropicExplicitApiKey:
 
     def test_try_anthropic_without_explicit_key_falls_back_to_resolve(self):
         """Without explicit_api_key, _try_anthropic falls back to resolve_anthropic_token."""
-        with patch("agent.anthropic_adapter.resolve_anthropic_token", return_value="env-fallback-key"), \
+        with patch("agent.anthropic_credentials.resolve_anthropic_token", return_value="env-fallback-key"), \
              patch("agent.anthropic_adapter.build_anthropic_client") as mock_build, \
              patch("agent.auxiliary_client._select_pool_entry", return_value=(False, None)):
             mock_build.return_value = MagicMock()
@@ -4052,7 +4052,7 @@ class TestAnthropicExplicitApiKey:
 
     def test_resolve_provider_client_passes_explicit_api_key_to_anthropic(self):
         """resolve_provider_client(provider='anthropic', explicit_api_key=...) must propagate the key."""
-        with patch("agent.anthropic_adapter.resolve_anthropic_token", return_value="env-key"), \
+        with patch("agent.anthropic_credentials.resolve_anthropic_token", return_value="env-key"), \
              patch("agent.anthropic_adapter.build_anthropic_client") as mock_build, \
              patch("agent.auxiliary_client._select_pool_entry", return_value=(False, None)):
             mock_build.return_value = MagicMock()
diff --git a/tests/agent/test_auxiliary_client_base_url_host_validation_52608.py b/tests/agent/test_auxiliary_client_base_url_host_validation_52608.py
index 478a366078..a55d01a07d 100644
--- a/tests/agent/test_auxiliary_client_base_url_host_validation_52608.py
+++ b/tests/agent/test_auxiliary_client_base_url_host_validation_52608.py
@@ -39,7 +39,7 @@ class TestTryAnthropicBaseUrlHostValidation:
                 "agent.auxiliary_client._select_pool_entry", return_value=(False, None)
             ),
             patch(
-                "agent.anthropic_adapter.resolve_anthropic_token",
+                "agent.anthropic_credentials.resolve_anthropic_token",
                 return_value="***",
             ),
             patch(
@@ -74,7 +74,7 @@ class TestTryAnthropicBaseUrlHostValidation:
                 "agent.auxiliary_client._select_pool_entry", return_value=(False, None)
             ),
             patch(
-                "agent.anthropic_adapter.resolve_anthropic_token",
+                "agent.anthropic_credentials.resolve_anthropic_token",
                 return_value="***",
             ),
             patch(
@@ -106,7 +106,7 @@ class TestTryAnthropicBaseUrlHostValidation:
                 "agent.auxiliary_client._select_pool_entry", return_value=(False, None)
             ),
             patch(
-                "agent.anthropic_adapter.resolve_anthropic_token",
+                "agent.anthropic_credentials.resolve_anthropic_token",
                 return_value="***",
             ),
             patch(
@@ -141,7 +141,7 @@ class TestTryAnthropicBaseUrlHostValidation:
                 "agent.auxiliary_client._select_pool_entry", return_value=(False, None)
             ),
             patch(
-                "agent.anthropic_adapter.resolve_anthropic_token",
+                "agent.anthropic_credentials.resolve_anthropic_token",
                 return_value="***",
             ),
             patch(
@@ -175,7 +175,7 @@ class TestTryAnthropicBaseUrlHostValidation:
                 "agent.auxiliary_client._select_pool_entry", return_value=(False, None)
             ),
             patch(
-                "agent.anthropic_adapter.resolve_anthropic_token",
+                "agent.anthropic_credentials.resolve_anthropic_token",
                 return_value="***",
             ),
             patch(
@@ -220,7 +220,7 @@ class TestTryAnthropicBaseUrlHostValidation:
                 "agent.auxiliary_client._select_pool_entry", return_value=(False, None)
             ),
             patch(
-                "agent.anthropic_adapter.resolve_anthropic_token",
+                "agent.anthropic_credentials.resolve_anthropic_token",
                 return_value="***",
             ),
             patch(
diff --git a/tests/agent/test_bedrock_integration.py b/tests/agent/test_bedrock_integration.py
index bd9da1cfe0..fb4476447b 100644
--- a/tests/agent/test_bedrock_integration.py
+++ b/tests/agent/test_bedrock_integration.py
@@ -290,7 +290,7 @@ class TestPackaging:
 #   us.anthropic.claude-sonnet-4-5-20250929-v1:0
 #   apac.anthropic.claude-haiku-4-5
 #
-# ``agent.anthropic_adapter.normalize_model_name`` converts dots to hyphens
+# ``agent.anthropic_message_convert.normalize_model_name`` converts dots to hyphens
 # unless the caller opts in via ``preserve_dots=True``.  Before this fix,
 # ``AIAgent._anthropic_preserve_dots`` returned False for the ``bedrock``
 # provider, so Claude-on-Bedrock requests went out with
@@ -339,7 +339,7 @@ class TestBedrockModelNameNormalization:
 
     def test_global_anthropic_inference_profile_preserved(self):
         """The reporter's exact model ID."""
-        from agent.anthropic_adapter import normalize_model_name
+        from agent.anthropic_message_convert import normalize_model_name
         assert normalize_model_name(
             "global.anthropic.claude-opus-4-7", preserve_dots=True
         ) == "global.anthropic.claude-opus-4-7"
@@ -351,7 +351,7 @@ class TestBedrockModelNameNormalization:
         always returned unmangled -- ``preserve_dots`` is irrelevant for
         these IDs because the dots are namespace separators, not version
         separators.  Regression for #12295."""
-        from agent.anthropic_adapter import normalize_model_name
+        from agent.anthropic_message_convert import normalize_model_name
         assert normalize_model_name(
             "global.anthropic.claude-opus-4-7", preserve_dots=False
         ) == "global.anthropic.claude-opus-4-7"
@@ -403,7 +403,7 @@ class TestBedrockModelIdDetection:
     regardless of ``preserve_dots``.  Regression for #12295."""
 
     def test_bare_bedrock_id_detected(self):
-        from agent.anthropic_adapter import _is_bedrock_model_id
+        from agent.anthropic_message_convert import _is_bedrock_model_id
         assert _is_bedrock_model_id("anthropic.claude-opus-4-7") is True
 
 
@@ -415,7 +415,7 @@ class TestBedrockModelIdDetection:
         """The primary bug from #12295: ``anthropic.claude-opus-4-7``
         sent to bedrock-mantle via auxiliary clients that don't pass
         ``preserve_dots=True``."""
-        from agent.anthropic_adapter import normalize_model_name
+        from agent.anthropic_message_convert import normalize_model_name
         assert normalize_model_name(
             "anthropic.claude-opus-4-7", preserve_dots=False
         ) == "anthropic.claude-opus-4-7"
diff --git a/tests/agent/test_credential_pool_oat_authtype.py b/tests/agent/test_credential_pool_oat_authtype.py
index 468e2b1e96..409d2c5397 100644
--- a/tests/agent/test_credential_pool_oat_authtype.py
+++ b/tests/agent/test_credential_pool_oat_authtype.py
@@ -53,7 +53,7 @@ def test_load_heals_legacy_row_and_exposes_it_to_resolver(tmp_path, monkeypatch)
         },
     }))
 
-    from agent.anthropic_adapter import resolve_anthropic_token
+    from agent.anthropic_credentials import resolve_anthropic_token
     from agent.credential_pool import load_pool
 
     entry = load_pool("anthropic").entries()[0]
diff --git a/tests/agent/test_deepseek_anthropic_thinking.py b/tests/agent/test_deepseek_anthropic_thinking.py
index 845f230de8..9f0dd66f00 100644
--- a/tests/agent/test_deepseek_anthropic_thinking.py
+++ b/tests/agent/test_deepseek_anthropic_thinking.py
@@ -35,7 +35,7 @@ class TestDeepSeekAnthropicPreservesThinking:
         DeepSeek issues its own signatures and cannot validate Anthropic's —
         the strip-signed / keep-unsigned split matches the Kimi policy.
         """
-        from agent.anthropic_adapter import convert_messages_to_anthropic
+        from agent.anthropic_message_convert import convert_messages_to_anthropic
 
         messages = [
             {"role": "user", "content": "hi"},
@@ -73,7 +73,7 @@ class TestDeepSeekAnthropicPreservesThinking:
         as ignored — cache markers interfere with signature validation on
         upstreams that do check them, so Hermes strips them everywhere.
         """
-        from agent.anthropic_adapter import convert_messages_to_anthropic
+        from agent.anthropic_message_convert import convert_messages_to_anthropic
 
         messages = [
             {"role": "user", "content": "hi"},
diff --git a/tests/agent/test_kimi_coding_anthropic_thinking.py b/tests/agent/test_kimi_coding_anthropic_thinking.py
index 309fa8a400..24a1180f9c 100644
--- a/tests/agent/test_kimi_coding_anthropic_thinking.py
+++ b/tests/agent/test_kimi_coding_anthropic_thinking.py
@@ -118,7 +118,7 @@ class TestKimiFamilyGetsAdaptiveThinking:
         blocks must survive the third-party signature-stripping pass so
         the upstream's message-history validation passes.
         """
-        from agent.anthropic_adapter import convert_messages_to_anthropic
+        from agent.anthropic_message_convert import convert_messages_to_anthropic
 
         messages = [
             {"role": "user", "content": "hi"},
diff --git a/tests/agent/test_meta_agent_init.py b/tests/agent/test_meta_agent_init.py
index 60be0da0bf..2d56453d10 100644
--- a/tests/agent/test_meta_agent_init.py
+++ b/tests/agent/test_meta_agent_init.py
@@ -97,7 +97,7 @@ def test_agent_init_anthropic_url_implies_provider_and_api_mode():
     from run_agent import AIAgent
 
     with patch("agent.anthropic_adapter.build_anthropic_client", return_value=MagicMock()), patch(
-        "agent.anthropic_adapter._is_oauth_token", return_value=False
+        "agent.anthropic_credentials._is_oauth_token", return_value=False
     ):
         agent = AIAgent(
             provider=None,
@@ -127,7 +127,7 @@ def test_agent_init_anthropic_url_preserves_credential_pool():
     pool = SimpleNamespace(provider="anthropic")
 
     with patch("agent.anthropic_adapter.build_anthropic_client", return_value=MagicMock()), patch(
-        "agent.anthropic_adapter._is_oauth_token", return_value=False
+        "agent.anthropic_credentials._is_oauth_token", return_value=False
     ):
         agent = AIAgent(
             provider=None,
diff --git a/tests/agent/test_minimax_provider.py b/tests/agent/test_minimax_provider.py
index bd50838337..a6996e8179 100644
--- a/tests/agent/test_minimax_provider.py
+++ b/tests/agent/test_minimax_provider.py
@@ -275,7 +275,7 @@ class TestMinimaxPreserveDots:
 
 
     def test_normalize_preserves_m25_free_dot(self):
-        from agent.anthropic_adapter import normalize_model_name
+        from agent.anthropic_message_convert import normalize_model_name
         assert normalize_model_name("minimax-m2.5-free", preserve_dots=True) == "minimax-m2.5-free"
 
 
@@ -312,8 +312,8 @@ class TestMinimaxSwitchModelCredentialGuard:
             agent._fallback_chain = []
 
         with patch("agent.anthropic_adapter.build_anthropic_client") as mock_build, \
-             patch("agent.anthropic_adapter.resolve_anthropic_token", return_value="sk-ant-leaked") as mock_resolve, \
-             patch("agent.anthropic_adapter._is_oauth_token", return_value=False):
+             patch("agent.anthropic_credentials.resolve_anthropic_token", return_value="sk-ant-leaked") as mock_resolve, \
+             patch("agent.anthropic_credentials._is_oauth_token", return_value=False):
 
             agent.switch_model(
                 new_model="MiniMax-M2.7",
diff --git a/tests/agent/test_none_deref_guards.py b/tests/agent/test_none_deref_guards.py
index 58ff72c456..7834ced543 100644
--- a/tests/agent/test_none_deref_guards.py
+++ b/tests/agent/test_none_deref_guards.py
@@ -6,7 +6,7 @@ a present-but-null value sails through as None and crashes any chained
 method call.
 """
 
-from agent.anthropic_adapter import _convert_user_message
+from agent.anthropic_message_convert import _convert_user_message
 from agent.moa_loop import _slot_label
 
 
diff --git a/tests/agent/test_nous_portal_anthropic_wire.py b/tests/agent/test_nous_portal_anthropic_wire.py
index 2b4521c87e..af85a6003e 100644
--- a/tests/agent/test_nous_portal_anthropic_wire.py
+++ b/tests/agent/test_nous_portal_anthropic_wire.py
@@ -172,10 +172,7 @@ class TestClientShape:
     def test_lookalike_host_does_not_get_portal_treatment(self):
         """Substring matching would hand a spoofed host the Portal JWT as a
         Bearer token. Hostname matching must reject it."""
-        from agent.anthropic_adapter import (
-            _is_nous_portal_endpoint,
-            _requires_bearer_auth,
-        )
+        from agent.anthropic_endpoints import _is_nous_portal_endpoint, _requires_bearer_auth
 
         spoofed = "https://inference-api.nousresearch.com.attacker.test/v1"
         assert not _is_nous_portal_endpoint(spoofed)
@@ -369,7 +366,7 @@ class TestPortalThinkingReplay:
         ]
 
     def _assert_thinking_kept(self, base_url):
-        from agent.anthropic_adapter import convert_messages_to_anthropic
+        from agent.anthropic_message_convert import convert_messages_to_anthropic
 
         _system, converted = convert_messages_to_anthropic(
             self._messages(),
@@ -402,7 +399,7 @@ class TestPortalThinkingReplay:
 
     def test_other_third_party_gateways_still_strip_thinking(self):
         """The Portal carve-out must not leak into MiniMax-style proxies."""
-        from agent.anthropic_adapter import convert_messages_to_anthropic
+        from agent.anthropic_message_convert import convert_messages_to_anthropic
 
         _system, converted = convert_messages_to_anthropic(
             self._messages(),
diff --git a/tests/agent/test_pydantic_dump_warning_leak.py b/tests/agent/test_pydantic_dump_warning_leak.py
index 48f18de71c..d17794bedc 100644
--- a/tests/agent/test_pydantic_dump_warning_leak.py
+++ b/tests/agent/test_pydantic_dump_warning_leak.py
@@ -101,7 +101,7 @@ def test_relay_tools_jsonable_no_warning_leak():
 
 
 def test_anthropic_to_plain_data_no_warning_leak():
-    from agent.anthropic_adapter import _to_plain_data
+    from agent.anthropic_message_convert import _to_plain_data
 
     _, snapshot = _accumulated_stop_event()
     with warnings.catch_warnings(record=True) as recorded:
@@ -126,7 +126,7 @@ def test_duck_typed_model_dump_fallback():
     """Non-pydantic objects with a bare model_dump() must still serialize."""
     from agent.relay_llm import _jsonable as rl_jsonable
     from agent.relay_tools import _jsonable as rt_jsonable
-    from agent.anthropic_adapter import _to_plain_data
+    from agent.anthropic_message_convert import _to_plain_data
 
     class Duck:
         def model_dump(self):  # no mode/warnings kwargs
diff --git a/tests/conftest.py b/tests/conftest.py
index e4dfb0ed06..fb62a748c2 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -631,21 +631,16 @@ def _neutralize_macos_keychain_creds(request, monkeypatch):
     if request.node.get_closest_marker(_ALLOW_MACOS_KEYCHAIN_MARK):
         return None
 
-    # Patch the implementation owner (agent.anthropic_credentials) AND the
-    # adapter re-export: after the adapter godfile split, the real call
-    # executes inside agent.anthropic_credentials, so patching only the
-    # adapter alias silently stopped intercepting Keychain reads.
-    for _module_name in ("agent.anthropic_credentials", "agent.anthropic_adapter"):
-        try:
-            _mod = importlib.import_module(_module_name)
-        except Exception:
-            continue
-        monkeypatch.setattr(
-            _mod,
-            "_read_claude_code_credentials_from_keychain",
-            lambda *_args, **_kwargs: None,
-            raising=False,
-        )
+    try:
+        _mod = importlib.import_module("agent.anthropic_credentials")
+    except Exception:
+        return None
+    monkeypatch.setattr(
+        _mod,
+        "_read_claude_code_credentials_from_keychain",
+        lambda *_args, **_kwargs: None,
+        raising=False,
+    )
     return None
 
 
diff --git a/tests/hermes_cli/test_anthropic_model_flow_stale_oauth.py b/tests/hermes_cli/test_anthropic_model_flow_stale_oauth.py
index 7691724459..40526514cd 100644
--- a/tests/hermes_cli/test_anthropic_model_flow_stale_oauth.py
+++ b/tests/hermes_cli/test_anthropic_model_flow_stale_oauth.py
@@ -27,7 +27,7 @@ class TestStaleOAuthTokenDetection:
 
         # No valid Claude Code credentials available (expired, no refresh token)
         monkeypatch.setattr(
-            "agent.anthropic_adapter.read_claude_code_credentials",
+            "agent.anthropic_credentials.read_claude_code_credentials",
             lambda: {
                 "accessToken": "expired-cc-token",
                 "refreshToken": "",          # No refresh — can't recover
@@ -36,16 +36,16 @@ class TestStaleOAuthTokenDetection:
             },
         )
         monkeypatch.setattr(
-            "agent.anthropic_adapter.is_claude_code_token_valid",
+            "agent.anthropic_credentials.is_claude_code_token_valid",
             lambda creds: False,             # Explicitly expired
         )
         monkeypatch.setattr(
-            "agent.anthropic_adapter._is_oauth_token",
+            "agent.anthropic_credentials._is_oauth_token",
             lambda key: key.startswith("sk-ant-"),
         )
         # _resolve_claude_code_token_from_credentials has no valid path
         monkeypatch.setattr(
-            "agent.anthropic_adapter._resolve_claude_code_token_from_credentials",
+            "agent.anthropic_credentials._resolve_claude_code_token_from_credentials",
             lambda creds=None: None,
         )
 
@@ -77,15 +77,15 @@ class TestStaleOAuthTokenDetection:
         save_env_value("ANTHROPIC_TOKEN", "")
 
         monkeypatch.setattr(
-            "agent.anthropic_adapter.read_claude_code_credentials",
+            "agent.anthropic_credentials.read_claude_code_credentials",
             lambda: None,   # No CC creds
         )
         monkeypatch.setattr(
-            "agent.anthropic_adapter.is_claude_code_token_valid",
+            "agent.anthropic_credentials.is_claude_code_token_valid",
             lambda creds: False,
         )
         monkeypatch.setattr(
-            "agent.anthropic_adapter._is_oauth_token",
+            "agent.anthropic_credentials._is_oauth_token",
             lambda key: key.startswith("sk-ant-") and "oat" in key,
         )
 
diff --git a/tests/hermes_cli/test_anthropic_oauth_flow.py b/tests/hermes_cli/test_anthropic_oauth_flow.py
index d9c06d2513..0213b05e95 100644
--- a/tests/hermes_cli/test_anthropic_oauth_flow.py
+++ b/tests/hermes_cli/test_anthropic_oauth_flow.py
@@ -6,11 +6,11 @@ from hermes_cli.config import load_env, save_env_value
 def test_run_anthropic_oauth_flow_prefers_claude_code_credentials(tmp_path, monkeypatch, capsys):
     monkeypatch.setenv("HERMES_HOME", str(tmp_path))
     monkeypatch.setattr(
-        "agent.anthropic_adapter.run_oauth_setup_token",
+        "agent.anthropic_credentials.run_oauth_setup_token",
         lambda: "sk-ant-oat01-from-claude-setup",
     )
     monkeypatch.setattr(
-        "agent.anthropic_adapter.read_claude_code_credentials",
+        "agent.anthropic_credentials.read_claude_code_credentials",
         lambda: {
             "accessToken": "cc-access-token",
             "refreshToken": "cc-refresh-token",
@@ -18,7 +18,7 @@ def test_run_anthropic_oauth_flow_prefers_claude_code_credentials(tmp_path, monk
         },
     )
     monkeypatch.setattr(
-        "agent.anthropic_adapter.is_claude_code_token_valid",
+        "agent.anthropic_credentials.is_claude_code_token_valid",
         lambda creds: True,
     )
 
@@ -36,9 +36,9 @@ def test_run_anthropic_oauth_flow_prefers_claude_code_credentials(tmp_path, monk
 
 def test_run_anthropic_oauth_flow_manual_token_still_persists(tmp_path, monkeypatch, capsys):
     monkeypatch.setenv("HERMES_HOME", str(tmp_path))
-    monkeypatch.setattr("agent.anthropic_adapter.run_oauth_setup_token", lambda: None)
-    monkeypatch.setattr("agent.anthropic_adapter.read_claude_code_credentials", lambda: None)
-    monkeypatch.setattr("agent.anthropic_adapter.is_claude_code_token_valid", lambda creds: False)
+    monkeypatch.setattr("agent.anthropic_credentials.run_oauth_setup_token", lambda: None)
+    monkeypatch.setattr("agent.anthropic_credentials.read_claude_code_credentials", lambda: None)
+    monkeypatch.setattr("agent.anthropic_credentials.is_claude_code_token_valid", lambda creds: False)
     monkeypatch.setattr("builtins.input", lambda _prompt="": "sk-ant-oat01-manual-token")
     monkeypatch.setattr(
         "hermes_cli.secret_prompt.masked_secret_prompt",
diff --git a/tests/hermes_cli/test_anthropic_pool_model_discovery.py b/tests/hermes_cli/test_anthropic_pool_model_discovery.py
index 74689a93fa..edeaa0fcdf 100644
--- a/tests/hermes_cli/test_anthropic_pool_model_discovery.py
+++ b/tests/hermes_cli/test_anthropic_pool_model_discovery.py
@@ -23,7 +23,7 @@ def test_anthropic_picker_discovers_models_with_pool_api_key(monkeypatch):
     """A direct API key stored only in auth.json must reach /v1/models."""
     monkeypatch.setattr(models, "_get_model_config_dict", lambda: {"provider": "nous"})
     monkeypatch.setattr(
-        "agent.anthropic_adapter.resolve_anthropic_token",
+        "agent.anthropic_credentials.resolve_anthropic_token",
         lambda: None,
     )
     monkeypatch.setattr(
@@ -71,7 +71,7 @@ def test_anthropic_pool_api_key_overrides_conflicting_active_endpoint(monkeypatc
         lambda: {"provider": "anthropic", "base_url": active_endpoint},
     )
     monkeypatch.setattr(
-        "agent.anthropic_adapter.resolve_anthropic_token",
+        "agent.anthropic_credentials.resolve_anthropic_token",
         lambda: None,
     )
     monkeypatch.setattr(
diff --git a/tests/hermes_cli/test_api_key_providers.py b/tests/hermes_cli/test_api_key_providers.py
index 16aee6c957..18fd8dd1fb 100644
--- a/tests/hermes_cli/test_api_key_providers.py
+++ b/tests/hermes_cli/test_api_key_providers.py
@@ -535,11 +535,11 @@ class TestHasAnyProviderConfigured:
         monkeypatch.setattr("hermes_cli.auth.get_auth_status", lambda _pid: {})
         # Simulate valid Claude Code credentials
         monkeypatch.setattr(
-            "agent.anthropic_adapter.read_claude_code_credentials",
+            "agent.anthropic_credentials.read_claude_code_credentials",
             lambda: {"accessToken": "sk-ant-test", "refreshToken": "ref-tok"},
         )
         monkeypatch.setattr(
-            "agent.anthropic_adapter.is_claude_code_token_valid",
+            "agent.anthropic_credentials.is_claude_code_token_valid",
             lambda creds: True,
         )
         from hermes_cli.main import _has_any_provider_configured
diff --git a/tests/hermes_cli/test_auth_commands.py b/tests/hermes_cli/test_auth_commands.py
index 29e992d2bd..682807add3 100644
--- a/tests/hermes_cli/test_auth_commands.py
+++ b/tests/hermes_cli/test_auth_commands.py
@@ -960,7 +960,7 @@ def test_seed_from_singletons_respects_hermes_pkce_suppression(tmp_path, monkeyp
     }))
 
     # Stub the readers so only hermes_pkce is "available"; claude_code returns None
-    import agent.anthropic_adapter as aa
+    import agent.anthropic_credentials as aa
     monkeypatch.setattr(aa, "read_hermes_oauth_credentials", lambda: {
         "accessToken": "tok", "refreshToken": "r", "expiresAt": 9999999999000,
     })
diff --git a/tests/hermes_cli/test_inventory.py b/tests/hermes_cli/test_inventory.py
index b4bf1fb92a..6726c55b3a 100644
--- a/tests/hermes_cli/test_inventory.py
+++ b/tests/hermes_cli/test_inventory.py
@@ -311,11 +311,11 @@ def test_anthropic_oauth_presence_accepts_pool_only_oauth_entry():
 
     with (
         patch(
-            "agent.anthropic_adapter.read_hermes_oauth_credentials",
+            "agent.anthropic_credentials.read_hermes_oauth_credentials",
             return_value=None,
         ),
         patch(
-            "agent.anthropic_adapter.read_claude_code_credentials",
+            "agent.anthropic_credentials.read_claude_code_credentials",
             return_value=None,
         ),
         patch(
@@ -331,11 +331,11 @@ def test_anthropic_oauth_presence_accepts_pool_only_oauth_entry():
     # (they are handled by the explicit-config gate / env var paths).
     with (
         patch(
-            "agent.anthropic_adapter.read_hermes_oauth_credentials",
+            "agent.anthropic_credentials.read_hermes_oauth_credentials",
             return_value=None,
         ),
         patch(
-            "agent.anthropic_adapter.read_claude_code_credentials",
+            "agent.anthropic_credentials.read_claude_code_credentials",
             return_value=None,
         ),
         patch(
diff --git a/tests/hermes_cli/test_model_switch_opencode_anthropic.py b/tests/hermes_cli/test_model_switch_opencode_anthropic.py
index c863356fef..faad9c4b30 100644
--- a/tests/hermes_cli/test_model_switch_opencode_anthropic.py
+++ b/tests/hermes_cli/test_model_switch_opencode_anthropic.py
@@ -154,8 +154,8 @@ class TestAgentSwitchModelDefenseInDepth:
         with patch(
             "agent.anthropic_adapter.build_anthropic_client",
             side_effect=_raise_after_capture,
-        ), patch("agent.anthropic_adapter.resolve_anthropic_token", return_value=""), patch(
-            "agent.anthropic_adapter._is_oauth_token", return_value=False
+        ), patch("agent.anthropic_credentials.resolve_anthropic_token", return_value=""), patch(
+            "agent.anthropic_credentials._is_oauth_token", return_value=False
         ):
             with pytest.raises(_Sentinel):
                 agent.switch_model(
diff --git a/tests/hermes_cli/test_runtime_provider_resolution.py b/tests/hermes_cli/test_runtime_provider_resolution.py
index 71614d0d27..35865157c6 100644
--- a/tests/hermes_cli/test_runtime_provider_resolution.py
+++ b/tests/hermes_cli/test_runtime_provider_resolution.py
@@ -1192,7 +1192,7 @@ class TestAzureAnthropicEnvVarHint:
             called["resolve_anthropic_token"] = True
             return "token-from-resolver"
         monkeypatch.setattr(
-            "agent.anthropic_adapter.resolve_anthropic_token",
+            "agent.anthropic_credentials.resolve_anthropic_token",
             _fake_resolve,
         )
 
diff --git a/tests/plugins/model_providers/test_commandcode_profile.py b/tests/plugins/model_providers/test_commandcode_profile.py
index e41a2bdc30..f7ce6b0244 100644
--- a/tests/plugins/model_providers/test_commandcode_profile.py
+++ b/tests/plugins/model_providers/test_commandcode_profile.py
@@ -156,14 +156,14 @@ class TestCommandCodeAnthropicBearerAuth:
     """
 
     def test_requires_bearer_auth_recognizes_commandcode(self):
-        from agent.anthropic_adapter import _requires_bearer_auth
+        from agent.anthropic_endpoints import _requires_bearer_auth
 
         assert _requires_bearer_auth("https://api.commandcode.ai/provider/v1") is True
         assert _requires_bearer_auth("https://api.commandcode.ai/provider/v1/models") is True
         assert _requires_bearer_auth("https://api.commandcode.ai/anthropic") is True
 
     def test_bearer_auth_does_not_affect_unrelated(self):
-        from agent.anthropic_adapter import _requires_bearer_auth
+        from agent.anthropic_endpoints import _requires_bearer_auth
 
         # Native Anthropic still uses x-api-key
         assert _requires_bearer_auth("https://api.anthropic.com") is False
@@ -171,7 +171,7 @@ class TestCommandCodeAnthropicBearerAuth:
         assert _requires_bearer_auth("https://openrouter.ai/api/v1") is False
 
     def test_bearer_auth_case_insensitive(self):
-        from agent.anthropic_adapter import _requires_bearer_auth
+        from agent.anthropic_endpoints import _requires_bearer_auth
 
         assert _requires_bearer_auth("https://API.COMMANDCODE.AI/provider/v1") is True
 
diff --git a/tests/run_agent/test_63425_credential_pool_auto_detect.py b/tests/run_agent/test_63425_credential_pool_auto_detect.py
index 5ac6dbcd9a..b89edf76cd 100644
--- a/tests/run_agent/test_63425_credential_pool_auto_detect.py
+++ b/tests/run_agent/test_63425_credential_pool_auto_detect.py
@@ -38,8 +38,8 @@ class TestCredentialPoolPreservedOnAutoDetect:
         with patch("agent.auxiliary_client.resolve_provider_client", return_value=(None, None)), \
              patch("run_agent.get_tool_definitions", return_value=[]), \
              patch('agent.anthropic_adapter.build_anthropic_client', return_value=MagicMock()), \
-             patch('agent.anthropic_adapter.resolve_anthropic_token', return_value=''), \
-             patch('agent.anthropic_adapter._is_oauth_token', return_value=False), \
+             patch('agent.anthropic_credentials.resolve_anthropic_token', return_value=''), \
+             patch('agent.anthropic_credentials._is_oauth_token', return_value=False), \
              patch('agent.azure_identity_adapter.is_token_provider', return_value=False), \
              patch('hermes_cli.model_normalize.normalize_model_for_provider', return_value='test-model'), \
              patch('agent.credential_pool.load_pool', return_value=MagicMock()), \
diff --git a/tests/run_agent/test_anthropic_third_party_oauth_guard.py b/tests/run_agent/test_anthropic_third_party_oauth_guard.py
index ea6dae0733..031ee0ca71 100644
--- a/tests/run_agent/test_anthropic_third_party_oauth_guard.py
+++ b/tests/run_agent/test_anthropic_third_party_oauth_guard.py
@@ -64,7 +64,7 @@ class TestOAuthFlagOnRefresh:
         agent._is_anthropic_oauth = False
 
         with (
-            patch("agent.anthropic_adapter.resolve_anthropic_token",
+            patch("agent.anthropic_credentials.resolve_anthropic_token",
                   return_value=_OAUTH_LIKE_TOKEN),
             patch("agent.anthropic_adapter.build_anthropic_client",
                   return_value=MagicMock()),
@@ -111,7 +111,7 @@ class TestOAuthFlagOnConstruction:
                   return_value=MagicMock()),
             # Simulate a stale ANTHROPIC_TOKEN in the env — the init code
             # MUST NOT fall back to it when provider != anthropic.
-            patch("agent.anthropic_adapter.resolve_anthropic_token",
+            patch("agent.anthropic_credentials.resolve_anthropic_token",
                   return_value=_OAUTH_LIKE_TOKEN),
         ):
             agent = AIAgent(
@@ -136,7 +136,7 @@ class TestOAuthFlagOnFallbackActivation:
 
     def test_fallback_to_third_party_does_not_flip_oauth(self, agent):
         """Directly mimic the post-fallback assignment at line ~6537."""
-        from agent.anthropic_adapter import _is_oauth_token
+        from agent.anthropic_credentials import _is_oauth_token
 
         # Emulate the relevant lines of _try_activate_fallback without
         # running the entire recovery stack (which pulls in streaming,
@@ -153,6 +153,6 @@ class TestApiKeyTokensAlwaysSafe:
     """Regression: plain API-key shapes must always resolve to non-OAuth, any provider."""
 
     def test_native_anthropic_with_api_key_token(self):
-        from agent.anthropic_adapter import _is_oauth_token
+        from agent.anthropic_credentials import _is_oauth_token
         assert _is_oauth_token(_API_KEY_TOKEN) is False
 
diff --git a/tests/run_agent/test_switch_model_fallback_prune.py b/tests/run_agent/test_switch_model_fallback_prune.py
index a01a60348c..3aee34183d 100644
--- a/tests/run_agent/test_switch_model_fallback_prune.py
+++ b/tests/run_agent/test_switch_model_fallback_prune.py
@@ -40,8 +40,8 @@ def _make_agent(chain):
 def _switch_to_anthropic(agent):
     with (
         patch("agent.anthropic_adapter.build_anthropic_client", return_value=MagicMock()),
-        patch("agent.anthropic_adapter.resolve_anthropic_token", return_value="sk-ant-xyz"),
-        patch("agent.anthropic_adapter._is_oauth_token", return_value=False),
+        patch("agent.anthropic_credentials.resolve_anthropic_token", return_value="sk-ant-xyz"),
+        patch("agent.anthropic_credentials._is_oauth_token", return_value=False),
         patch("hermes_cli.timeouts.get_provider_request_timeout", return_value=None),
     ):
         agent.switch_model(
diff --git a/tests/run_agent/test_switch_model_rollback.py b/tests/run_agent/test_switch_model_rollback.py
index d5a1abf2c0..6009a6ce10 100644
--- a/tests/run_agent/test_switch_model_rollback.py
+++ b/tests/run_agent/test_switch_model_rollback.py
@@ -127,10 +127,10 @@ def test_anthropic_client_rebuild_failure_rolls_back_to_original_state():
             side_effect=RuntimeError("simulated anthropic build failure"),
         ),
         patch(
-            "agent.anthropic_adapter.resolve_anthropic_token",
+            "agent.anthropic_credentials.resolve_anthropic_token",
             return_value="sk-ant-resolved",
         ),
-        patch("agent.anthropic_adapter._is_oauth_token", return_value=False),
+        patch("agent.anthropic_credentials._is_oauth_token", return_value=False),
         patch("hermes_cli.timeouts.get_provider_request_timeout", return_value=None),
     ):
         with pytest.raises(RuntimeError, match="simulated anthropic build failure"):
diff --git a/tests/test_hermetic_side_effect_guards.py b/tests/test_hermetic_side_effect_guards.py
index 983e6c44ad..d9df5ca01d 100644
--- a/tests/test_hermetic_side_effect_guards.py
+++ b/tests/test_hermetic_side_effect_guards.py
@@ -33,14 +33,11 @@ def test_webbrowser_get_controller_is_neutralized(_neutralize_webbrowser):
 
 
 def _isolate_anthropic_credentials(monkeypatch, tmp_path):
-    from agent import anthropic_adapter as aa
     from agent import anthropic_credentials as ac
 
     monkeypatch.delenv("ANTHROPIC_API_KEY", raising=False)
     monkeypatch.delenv("ANTHROPIC_TOKEN", raising=False)
     monkeypatch.delenv("CLAUDE_CODE_OAUTH_TOKEN", raising=False)
-    # Patch the implementation owner (anthropic_credentials); the adapter
-    # merely re-exports these functions after the godfile split.
     monkeypatch.setattr(ac.Path, "home", lambda: tmp_path)
     monkeypatch.setattr(ac.platform, "system", lambda: "Darwin")
 
@@ -48,22 +45,22 @@ def _isolate_anthropic_credentials(monkeypatch, tmp_path):
         raise AssertionError("test reached the real macOS Keychain command")
 
     monkeypatch.setattr(ac.subprocess, "run", _real_keychain_reached)
-    return aa
+    return ac
 
 
 def test_claude_code_credential_read_does_not_touch_macos_keychain(
     monkeypatch, tmp_path
 ):
     """The real credential reader should be safe under the suite guard."""
-    aa = _isolate_anthropic_credentials(monkeypatch, tmp_path)
+    ac = _isolate_anthropic_credentials(monkeypatch, tmp_path)
 
-    assert aa.read_claude_code_credentials() is None
+    assert ac.read_claude_code_credentials() is None
 
 
 def test_anthropic_token_resolution_does_not_touch_macos_keychain(
     monkeypatch, tmp_path
 ):
     """Token resolution should be safe under the same suite guard."""
-    aa = _isolate_anthropic_credentials(monkeypatch, tmp_path)
+    ac = _isolate_anthropic_credentials(monkeypatch, tmp_path)
 
-    assert aa.resolve_anthropic_token() is None
+    assert ac.resolve_anthropic_token() is None
diff --git a/tests/tools/test_computer_use.py b/tests/tools/test_computer_use.py
index b5a0cfd1b4..eb4df4175c 100644
--- a/tests/tools/test_computer_use.py
+++ b/tests/tools/test_computer_use.py
@@ -406,7 +406,7 @@ class TestCuaCaptureImageDimensions:
 
 class TestAnthropicAdapterMultimodal:
     def test_multimodal_envelope_becomes_tool_result_with_image_block(self):
-        from agent.anthropic_adapter import convert_messages_to_anthropic
+        from agent.anthropic_message_convert import convert_messages_to_anthropic
 
         fake_png = "iVBORw0KGgo="
         messages = [
@@ -446,7 +446,7 @@ class TestAnthropicAdapterMultimodal:
 
     def test_old_screenshots_are_evicted_beyond_max_keep(self):
         """Image blocks in old tool_results get replaced with placeholders."""
-        from agent.anthropic_adapter import convert_messages_to_anthropic
+        from agent.anthropic_message_convert import convert_messages_to_anthropic
 
         fake_png = "iVBORw0KGgo="