Fix Codex provider routing for GitHub Copilot models

nanobot/config/schema.py

@@ -287,11 +287,34 @@ class Config(BaseSettings):
         from nanobot.providers.registry import PROVIDERS
 
         model_lower = (model or self.agents.defaults.model).lower()
+        model_normalized = model_lower.replace("-", "_")
+        model_prefix = model_lower.split("/", 1)[0] if "/" in model_lower else ""
+        normalized_prefix = model_prefix.replace("-", "_")
+
+        def _matches_model_prefix(spec_name: str) -> bool:
+            if not model_prefix:
+                return False
+            return normalized_prefix == spec_name
+
+        def _keyword_matches(keyword: str) -> bool:
+            keyword_lower = keyword.lower()
+            return (
+                keyword_lower in model_lower
+                or keyword_lower.replace("-", "_") in model_normalized
+            )
+
+        # Explicit provider prefix in model name wins over generic keyword matches.
+        # This prevents `github-copilot/...codex` from being treated as OpenAI Codex.
+        for spec in PROVIDERS:
+            p = getattr(self.providers, spec.name, None)
+            if p and _matches_model_prefix(spec.name):
+                if spec.is_oauth or p.api_key:
+                    return p, spec.name
 
         # Match by keyword (order follows PROVIDERS registry)
         for spec in PROVIDERS:
             p = getattr(self.providers, spec.name, None)
-            if p and any(kw in model_lower for kw in spec.keywords):
+            if p and any(_keyword_matches(kw) for kw in spec.keywords):
                 if spec.is_oauth or p.api_key:
                     return p, spec.name