Adding OpenRouter as a new model provider.

Author: Oxyjun

src/content/docs/ai-gateway/providers/open-router.mdx

@@ -0,0 +1,66 @@
+---
+title: OpenRouter
+pcx_content_type: get-started
+sidebar:
+  badge:
+    text: Beta
+---
+
+[OpenRouter](https://openrouter.ai/) is a platform that provides a unified interface for accessing and using large language models (LLMs).
+
+## Endpoint
+
+```txt
+https://gateway.ai.cloudflare.com/v1/{account_id}/{gateway_id}/openrouter
+```
+
+## URL structure
+
+When making requests to [OpenRouter](https://openrouter.ai/), replace `https://openrouter.ai/api/v1/chat/completions` in the URL you are currently using with `https://gateway.ai.cloudflare.com/v1/{account_id}/{gateway_id}/openrouter`.
+
+## Examples
+
+### cURL
+
+```bash title="Request"
+curl -X POST https://gateway.ai.cloudflare.com/v1/ACCOUNT_TAG/GATEWAY/openrouter/v1/chat/completions \
+ --header 'content-type: application/json' \
+ --header 'Authorization: Bearer OPENROUTER_TOKEN' \
+ --data '{
+    "model": "openai/gpt-3.5-turbo",
+    "messages": [
+        {
+            "role": "user",
+            "content": "What is Cloudflare?"
+        }
+    ]
+}'
+
+```
+
+### OpenAI SDK with JavaScript
+
+If you are using the OpenAI SDK with JavaScript, you can set your endpoint like this:
+
+```js title="JavaScript"
+import OpenAI from 'openai';
+
+const openai = new OpenAI({
+ apiKey: env.OPENROUTER_TOKEN,
+ baseURL: "https://gateway.ai.cloudflare.com/v1/ACCOUNT_TAG/GATEWAY/openrouter"
+});
+
+try {
+  const chatCompletion = await openai.chat.completions.create({
+    model: "openai/gpt-3.5-turbo",
+    messages: [{ role: "user", content: "What is Cloudflare?" }]
+  });
+
+  const response = chatCompletion.choices[0].message;
+
+  return new Response(JSON.stringify(response));
+} catch (e) {
+  return new Response(e);
+}
+
+```