gpt-5.1-codex — API, Pricing & Context Window | Vivgrid

gpt-5.1-codex is OpenAI's Codex-tuned 5.1 coding model, designed for agentic software engineering through the Responses API. It is a well-rounded, cost-effective option for everyday coding agents.

Vivgrid accelerates gpt-5.1-codex across AMER, EMEA, and APAC — the broadest reach in the Codex line — with a 400K-token context window for project-scale sessions.

Specifications

Pricing

Pricing in USD per 1M tokens, matching the provider's rates.

Quick start

Call gpt-5.1-codex through Vivgrid's unified, OpenAI-compatible endpoint. Get an API key from the Vivgrid Console.

curl https://api.vivgrid.com/v1/responses \
  -H "Authorization: Bearer $VIVGRID_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "gpt-5.1-codex",
    "input": "Refactor this function and explain the change.",
    "stream": true
  }'

Ideal use cases

• Day-to-day coding agents on the Responses API
• Globally distributed teams needing low latency in three regions
• Automated edits, reviews, and test generation
• Tool-calling workflows that chain editor and shell actions

Related models

• gpt-5.1-codex-max — extended-effort variant
• gpt-5.2-codex — the next Codex generation
• gpt-5.1 — general-purpose 5.1 model