reroute

OpenAI: GPT-5.1-Codex-Max

openai/gpt-5.1-codex-max
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GPT-5.1-Codex-Max is OpenAI’s latest agentic coding model, designed for long-running, high-context software development tasks. It is based on an updated version of the 5.1 reasoning stack and trained on agentic...

Modalities
In / Out Price
$1.25 / $10 per 1M
Context
400K
Released
Dec 4, 2025
Knowledge Cutoff
—

API

Reroute speaks the OpenAI Chat Completions format. Point any OpenAI SDK at https://reroute.wtf/api/v1 and use openai/gpt-5.1-codex-max as the model.

You need an API key
Keys start with sk-rr-v1- and are shown once.
Create API key
curl https://reroute.wtf/api/v1/chat/completions \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer $REROUTE_API_KEY" \
  -d '{
  "model": "openai/gpt-5.1-codex-max",
  "messages": [
    { "role": "user", "content": "What is the meaning of life?" }
  ]
}'

Streaming

Set stream: true to receive server-sent events. The final chunk carries usage and cost.

curl -N https://reroute.wtf/api/v1/chat/completions \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer $REROUTE_API_KEY" \
  -d '{ "model": "openai/gpt-5.1-codex-max", "stream": true,
        "messages": [{ "role": "user", "content": "Count to five" }] }'