docs: add Modelflare custom endpoint example

content/docs/configuration/librechat_yaml/ai_endpoints/meta.json

@@ -17,6 +17,7 @@
     "litellm",
     "mistral",
     "mlx",
+    "modelflare",
     "moonshot",
     "nearai",
     "neurochain",

content/docs/configuration/librechat_yaml/ai_endpoints/modelflare.mdx

@@ -0,0 +1,41 @@
+---
+title: Modelflare
+icon: Plug
+description: Configure Modelflare as a custom endpoint in LibreChat.
+---
+
+[Modelflare](https://modelflare.dev) is an AI API gateway that serves chat models from several providers through one OpenAI-compatible endpoint and one API key. See the [Modelflare docs](https://docs.modelflare.dev) for details.
+
+## Get an API key
+
+Create an account at [modelflare.dev](https://modelflare.dev) and create a key on the [API Keys page](https://modelflare.dev/keys). A Smart API Key can call every model available to your account. A regular key only calls the models of its own group. Add the key to your `.env` file:
+
+```bash filename=".env"
+MODELFLARE_API_KEY=your-api-key
+```
+
+## Configuration
+
+Add the endpoint to the `custom` list under `endpoints` in your `librechat.yaml`. If your file already has an `endpoints.custom` list, paste only the `- name:` entry into it, keeping the same indentation:
+
+```yaml filename="librechat.yaml"
+endpoints:
+  custom:
+    - name: "Modelflare"
+      apiKey: "${MODELFLARE_API_KEY}"
+      baseURL: "https://modelflare.dev/v1"
+      models:
+        default: ["gpt-5.6-sol"]
+        fetch: true
+      titleConvo: true
+      titleModel: "current_model"
+      modelDisplayLabel: "Modelflare"
+```
+
+To let each user supply their own key through the LibreChat UI instead of reading one from `.env`, set `apiKey: "user_provided"`. Users then see a key input field when they select the endpoint.
+
+## Notes
+
+- With `fetch: true`, LibreChat loads the models your key can call from `GET https://modelflare.dev/v1/models`. Use the exact model `id` from that list or from [Models & Pricing](https://modelflare.dev/pricing).
+- For deployments in mainland China, `https://origin.modelflare.dev/v1` serves the same API and can be used as the `baseURL`.
+- A `model_not_found` error means the key cannot reach that model. Use a Smart API Key or a key whose group includes the model.