Feature：Enhance backend model validate response (#397)

Author: Wendong-Fan

backend/app/component/error_format.py

@@ -0,0 +1,72 @@
+import json
+import re
+
+
+def normalize_error_to_openai_format(exception: Exception) -> tuple[str, str | None, dict | None]:
+    """
+    Normalize error to OpenAI-style error structure.
+
+    Args:
+        exception: The exception to normalize
+
+    Returns:
+        tuple: (message, error_code, error_object)
+    """
+    raw_msg = str(exception)
+    error_obj = None
+    error_code = None
+    message = raw_msg
+
+    # Match "Error code: <code> - {json}"
+    m = re.search(r"Error code:\s*(\d+)\s*-\s*(\{.*\})", raw_msg, re.DOTALL)
+    if m:
+        error_code = m.group(1)
+        try:
+            parsed = json.loads(m.group(2))
+            err = parsed.get("error") or parsed
+            if isinstance(err, dict):
+                error_obj = {
+                    "message": err.get("message"),
+                    "type": err.get("type"),
+                    "param": err.get("param"),
+                    "code": err.get("code"),
+                }
+                if err.get("message"):
+                    message = err.get("message")
+                if err.get("code"):
+                    error_code = err.get("code")
+        except Exception:
+            pass
+
+    # Heuristics if not parsed
+    if error_obj is None:
+        lower = raw_msg.lower()
+        if "invalid_api_key" in lower or "incorrect api key" in lower or "unauthorized" in lower or " 401" in lower:
+            error_code = "invalid_api_key"
+            message = "Invalid key. Validation failed."
+            error_obj = {
+                "message": message,
+                "type": "invalid_request_error",
+                "param": None,
+                "code": "invalid_api_key",
+            }
+        elif "model_not_found" in lower or "does not exist" in lower or " 404" in lower:
+            error_code = "model_not_found"
+            message = "Invalid model name. Validation failed."
+            error_obj = {
+                "message": message,
+                "type": "invalid_request_error",
+                "param": None,
+                "code": "model_not_found",
+            }
+        elif "insufficient_quota" in lower or "quota" in lower or " 429" in lower:
+            error_code = "insufficient_quota"
+            message = "You exceeded your current quota, please check your plan and billing details."
+            error_obj = {
+                "message": message,
+                "type": "insufficient_quota",
+                "param": None,
+                "code": "insufficient_quota",
+            }
+
+    return message, error_code, error_obj

backend/app/controller/model_controller.py

@@ -1,6 +1,8 @@
 from fastapi import APIRouter
 from pydantic import BaseModel, Field
 from app.component.model_validation import create_agent
+from camel.types import ModelType
+from app.component.error_format import normalize_error_to_openai_format
 
 
 router = APIRouter(tags=["model"])
@@ -18,12 +20,48 @@ class ValidateModelRequest(BaseModel):
 class ValidateModelResponse(BaseModel):
     is_valid: bool = Field(..., description="Is valid")
     is_tool_calls: bool = Field(..., description="Is tool call used")
+    error_code: str | None = Field(None, description="Error code")
+    error: dict | None = Field(None, description="OpenAI-style error object")
     message: str = Field(..., description="Message")
 
 
 @router.post("/model/validate")
 async def validate_model(request: ValidateModelRequest):
     try:
+        # 1) API key validation
+        if request.api_key is not None and str(request.api_key).strip() == "":
+            return ValidateModelResponse(
+                is_valid=False,
+                is_tool_calls=False,
+                message="Invalid key. Validation failed.",
+                error_code="invalid_api_key",
+                error={
+                    "message": "Invalid key. Validation failed.",
+                    "type": "invalid_request_error",
+                    "param": None,
+                    "code": "invalid_api_key",
+                },
+            )
+
+        # 2) Model name validation
+        if request.model_type:
+            try:
+                # Will raise if not a valid enum name
+                _ = ModelType.from_name(request.model_type)
+            except Exception as e:
+                return ValidateModelResponse(
+                    is_valid=False,
+                    is_tool_calls=False,
+                    message="Invalid model name. Validation failed.",
+                    error_code=f"model_not_found : {e}",
+                    error={
+                        "message": "Invalid model name. Validation failed.",
+                        "type": "invalid_request_error",
+                        "param": None,
+                        "code": "model_not_found",
+                    },
+                )
+
         extra = request.extra_params or {}
 
         agent = create_agent(
@@ -43,17 +81,33 @@ async def validate_model(request: ValidateModelRequest):
             """
         )
     except Exception as e:
-        return ValidateModelResponse(is_valid=False, is_tool_calls=False, message=str(e))
+        # Normalize error to OpenAI-style error structure
+        message, error_code, error_obj = normalize_error_to_openai_format(e)
+
+        return ValidateModelResponse(
+            is_valid=False,
+            is_tool_calls=False,
+            message=message,
+            error_code=error_code,
+            error=error_obj,
+        )
     is_valid = bool(response)
     is_tool_calls = False
-    
-    if response and hasattr(response, 'info') and response.info:
+
+    if response and hasattr(response, "info") and response.info:
         tool_calls = response.info.get("tool_calls", [])
         if tool_calls and len(tool_calls) > 0:
-            is_tool_calls = tool_calls[0].result == "Tool execution completed successfully for https://www.camel-ai.org, Website Content: Welcome to CAMEL AI!"
-    
+            is_tool_calls = (
+                tool_calls[0].result
+                == "Tool execution completed successfully for https://www.camel-ai.org, Website Content: Welcome to CAMEL AI!"
+            )
+
     return ValidateModelResponse(
         is_valid=is_valid,
         is_tool_calls=is_tool_calls,
-        message="",
+        message="Validation Success"
+        if is_tool_calls
+        else "This model doesn't support tool calls. please try with another model.",
+        error_code=None,
+        error=None,
     )