OpenAI

Route your OpenAI requests through Metrion to track token usage, costs, and latency — with a one-line SDK change.

Use Metrion as a drop-in proxy for OpenAI’s API. Point the OpenAI SDK at Metrion’s endpoint and use your sk-metrion-xxx token as the API key. Everything else stays the same.

Prerequisites

• A Metrion account with your sk-metrion-xxx token (find it on the Integrate page)
• An OpenAI API key saved in Metrion’s Integrate page

Setup

1. Install the OpenAI SDK
2. TypeScript

   npm install openai
   

   Python

   pip install openai
   
3. Configure the client
4. Set baseURL to Metrion’s OpenAI proxy and pass your sk-metrion-xxx token as apiKey. The proxy forwards requests to https://api.openai.com/v1/chat/completions and logs usage to your dashboard.
5. TypeScript

   import OpenAI from 'openai'
   
   const client = new OpenAI({
     apiKey: 'sk-metrion-xxx',       // your Metrion token
     baseURL: 'https://www.metrion.dev/api/proxy/openai',
   })
   

   Python

   from openai import OpenAI
   
   client = OpenAI(
       api_key="sk-metrion-xxx",     # your Metrion token
       base_url="https://www.metrion.dev/api/proxy/openai",
   )
   
6. Send a request
7. TypeScript

   import OpenAI from 'openai'
   
   const client = new OpenAI({
     apiKey: 'sk-metrion-xxx',
     baseURL: 'https://www.metrion.dev/api/proxy/openai',
   })
   
   const message = await client.chat.completions.create({
     model: 'gpt-4o',
     max_tokens: 1024,
     messages: [{ role: 'user', content: 'Hello, world!' }],
   })
   
   console.log(message.choices[0].message.content)
   

   Python

   from openai import OpenAI
   
   client = OpenAI(
       api_key="sk-metrion-xxx",
       base_url="https://www.metrion.dev/api/proxy/openai",
   )
   
   message = client.chat.completions.create(
       model="gpt-4o",
       max_tokens=1024,
       messages=[{"role": "user", "content": "Hello, world!"}],
   )
   
   print(message.choices[0].message.content)
   

Direct HTTP

curl https://www.metrion.dev/api/proxy/openai/v1/chat/completions \
  -H 'Authorization: Bearer sk-metrion-xxx' \
  -H 'content-type: application/json' \
  -d '{
    "model": "gpt-4o",
    "max_tokens": 1024,
    "messages": [{"role": "user", "content": "Hello, world!"}]
  }'

Supported models

Model ID	Notes
gpt-4o	Latest multimodal flagship
gpt-4o-mini	Fast and cost-efficient
gpt-4-turbo	High-context window
gpt-3.5-turbo	Low-cost general purpose
o1	Advanced reasoning
o3-mini	Compact reasoning model

Metrion uses prefix matching for versioned model IDs (e.g. gpt-4o-mini-2024-07-18 resolves to gpt-4o-mini pricing).

Pass-through mode

To use your own OpenAI key without storing it in Metrion, pass it in Authorization: Bearer and identify your Metrion account with the x-metrion-token header:

TypeScript

import OpenAI from 'openai'

const client = new OpenAI({
  apiKey: process.env.OPENAI_API_KEY,      // your OpenAI key directly
  baseURL: 'https://www.metrion.dev/api/proxy/openai',
  defaultHeaders: {
    'x-metrion-token': 'sk-metrion-xxx',   // identifies your Metrion account
  },
})

In pass-through mode, your OpenAI key is forwarded directly to OpenAI’s API and is never stored by Metrion.

Track requests by user or service

Add the optional x-metrion-user header to tag individual requests. These labels appear in your Metrion logs and dashboards.

Use x-metrion-user to break down costs by team member, bot, or application — for example "x-metrion-user": "agent-classifier" or "x-metrion-user": "user-99".

TypeScript

const client = new OpenAI({
  apiKey: 'sk-metrion-xxx',
  baseURL: 'https://www.metrion.dev/api/proxy/openai',
  defaultHeaders: {
    'x-metrion-user': 'user-99',
  },
})