From b64d0c76020ab78b96a6f2c357ffb4ff32ec2f25 Mon Sep 17 00:00:00 2001
From: Teknium <127238744+teknium1@users.noreply.github.com>
Date: Wed, 2 Sep 2026 19:08:44 -0700
Subject: [PATCH] refactor(gateway): phase helpers for
 _resolve_gateway_model_context (differentially fuzzed, 3072 cases)

---
 gateway/run.py | 89 +++++++++++++++++++++-----------------------------
 1 file changed, 38 insertions(+), 51 deletions(-)

diff --git a/gateway/run.py b/gateway/run.py
index 9d2ac86333..11f5bb627e 100644
--- a/gateway/run.py
+++ b/gateway/run.py
@@ -2516,68 +2516,55 @@ def _resolve_gateway_model_context(model: Optional[str] = None) -> _GatewayModel
     from agent.model_metadata import DEFAULT_FALLBACK_CONTEXT, get_model_context_length
 
     resolved_model = model or _resolve_gateway_model()
-    config_context_length = None
-    provider = None
-    base_url = None
-    api_key = None
-    custom_providers = None
-    configured_model = None
-    configured_provider = None
-    configured_base_url = None
+    config_context_length = provider = base_url = api_key = custom_providers = None
+    configured_model = configured_provider = configured_base_url = None
 
-    try:
+    def _read_config() -> None:
+        nonlocal config_context_length, provider, base_url, custom_providers
+        nonlocal configured_model, configured_provider, configured_base_url
         data = _load_gateway_config()
-        if data:
-            model_cfg = data.get("model", {})
-            if isinstance(model_cfg, dict):
-                configured_model = model_cfg.get("default") or model_cfg.get("model")
-                raw_ctx = model_cfg.get("context_length")
-                if raw_ctx is not None:
-                    with suppress(TypeError, ValueError):
-                        config_context_length = int(raw_ctx)
-                provider = model_cfg.get("provider") or None
-                base_url = model_cfg.get("base_url") or None
-                configured_provider = provider
-                configured_base_url = base_url
-            try:
-                from hermes_cli.config import get_compatible_custom_providers
+        if not data:
+            return
+        model_cfg = data.get("model", {})
+        if isinstance(model_cfg, dict):
+            configured_model = model_cfg.get("default") or model_cfg.get("model")
+            raw_ctx = model_cfg.get("context_length")
+            if raw_ctx is not None:
+                with suppress(TypeError, ValueError):
+                    config_context_length = int(raw_ctx)
+            configured_provider = provider = model_cfg.get("provider") or None
+            configured_base_url = base_url = model_cfg.get("base_url") or None
+        try:
+            from hermes_cli.config import get_compatible_custom_providers
+            custom_providers = get_compatible_custom_providers(data)
+        except Exception:
+            custom_providers = data.get("custom_providers")
 
-                custom_providers = get_compatible_custom_providers(data)
-            except Exception:
-                custom_providers = data.get("custom_providers")
-    except Exception:
-        pass
-
-    try:
+    def _read_runtime() -> None:
+        nonlocal provider, base_url, api_key
         runtime = _resolve_runtime_agent_kwargs()
         provider = runtime.get("provider") or provider
         base_url = runtime.get("base_url") or base_url
         api_key = runtime.get("api_key")
-    except Exception:
-        pass
 
-    if config_context_length is not None:
-        try:
-            from hermes_cli.route_identity import should_clear_context_pin
+    def _pin_still_applies() -> bool:
+        # A configured context_length pin is dropped when the effective route no longer matches the
+        # configured one; an unresolvable check also drops it.
+        from hermes_cli.route_identity import should_clear_context_pin
+        return not should_clear_context_pin(
+            configured_model, resolved_model, configured_base_url, base_url, configured_provider, provider)
 
-            if should_clear_context_pin(
-                configured_model, resolved_model, configured_base_url, base_url,
-                configured_provider, provider):
-                config_context_length = None
-        except Exception:
-            config_context_length = None
+    def _custom_ctx() -> Optional[int]:
+        from hermes_cli.config import get_custom_provider_context_length
+        return get_custom_provider_context_length(
+            model=resolved_model, base_url=base_url, custom_providers=custom_providers)
 
+    _best_effort(_read_config)
+    _best_effort(_read_runtime)
+    if config_context_length is not None and not _best_effort(_pin_still_applies):
+        config_context_length = None
     if config_context_length is None and custom_providers and base_url:
-        try:
-            from hermes_cli.config import get_custom_provider_context_length
-
-            custom_ctx = get_custom_provider_context_length(
-                model=resolved_model, base_url=base_url, custom_providers=custom_providers
-            )
-            if custom_ctx:
-                config_context_length = custom_ctx
-        except Exception:
-            pass
+        config_context_length = _best_effort(_custom_ctx) or None
 
     context_length = get_model_context_length(
         resolved_model, base_url=base_url or "", api_key=api_key or "",