docs: clarify OpenRouter configuration (#1123)

Co-authored-by: Willem Jiang <willem.jiang@gmail.com>

README.md

@@ -94,8 +94,16 @@ DeerFlow has newly integrated the intelligent search and crawling toolset indepe
        api_key: $OPENAI_API_KEY          # API key (recommended: use env var)
        max_tokens: 4096                  # Maximum tokens per request
        temperature: 0.7                  # Sampling temperature
+
+     - name: openrouter-gemini-2.5-flash
+       display_name: Gemini 2.5 Flash (OpenRouter)
+       use: langchain_openai:ChatOpenAI
+       model: google/gemini-2.5-flash-preview
+       api_key: $OPENAI_API_KEY          # OpenRouter still uses the OpenAI-compatible field name here
+       base_url: https://openrouter.ai/api/v1
    ```
 
+   OpenRouter and similar OpenAI-compatible gateways should be configured with `langchain_openai:ChatOpenAI` plus `base_url`. If you prefer a provider-specific environment variable name, point `api_key` at that variable explicitly (for example `api_key: $OPENROUTER_API_KEY`).
 
 4. **Set API keys for your configured model(s)**
 
@@ -107,6 +115,7 @@ DeerFlow has newly integrated the intelligent search and crawling toolset indepe
    ```bash
    TAVILY_API_KEY=your-tavily-api-key
    OPENAI_API_KEY=your-openai-api-key
+   # OpenRouter also uses OPENAI_API_KEY when your config uses langchain_openai:ChatOpenAI + base_url.
    # Add other provider keys as needed
    INFOQUEST_API_KEY=your-infoquest-api-key
    ```

backend/docs/CONFIGURATION.md

@@ -25,7 +25,7 @@ models:
 - DeepSeek (`langchain_deepseek:ChatDeepSeek`)
 - Any LangChain-compatible provider
 
-For OpenAI-compatible gateways (for example Novita), keep using `langchain_openai:ChatOpenAI` and set `base_url`:
+For OpenAI-compatible gateways (for example Novita or OpenRouter), keep using `langchain_openai:ChatOpenAI` and set `base_url`:
 
 ```yaml
 models:
@@ -40,8 +40,17 @@ models:
       extra_body:
         thinking:
           type: enabled
+
+  - name: openrouter-gemini-2.5-flash
+    display_name: Gemini 2.5 Flash (OpenRouter)
+    use: langchain_openai:ChatOpenAI
+    model: google/gemini-2.5-flash-preview
+    api_key: $OPENAI_API_KEY
+    base_url: https://openrouter.ai/api/v1
 ```
 
+If your OpenRouter key lives in a different environment variable name, point `api_key` at that variable explicitly (for example `api_key: $OPENROUTER_API_KEY`).
+
 **Thinking Models**:
 Some models support "thinking" mode for complex reasoning:
 

config.example.yaml

@@ -106,6 +106,17 @@ models:
   #       thinking:
   #         type: enabled
 
+  # Example: OpenRouter (OpenAI-compatible)
+  # OpenRouter models use the same ChatOpenAI + base_url pattern as other OpenAI-compatible gateways.
+  # - name: openrouter-gemini-2.5-flash
+  #   display_name: Gemini 2.5 Flash (OpenRouter)
+  #   use: langchain_openai:ChatOpenAI
+  #   model: google/gemini-2.5-flash-preview
+  #   api_key: $OPENAI_API_KEY
+  #   base_url: https://openrouter.ai/api/v1
+  #   max_tokens: 8192
+  #   temperature: 0.7
+
 # ============================================================================
 # Tool Groups Configuration
 # ============================================================================