Install

GPT-5.5 as a coding agent in your terminal

GPT-5.5 by OpenAI, one of 250+ models you can use in Darce, the open source AI coding agent you can undo.

ModelGPT-5.5
VendorOpenAI
Model idopenai/gpt-5.5
Context window1.05M tokens
Price per 1M tokens$5.00 input · $30.00 output (OpenRouter)
Can dotool calling · reads images · reasoning
CategoryReasoning

Strengths

A GPT-5.5 model with a 1M context window. A dependable choice for large repositories.

OpenRouter's description:

GPT-5.5 is OpenAI’s frontier model designed for complex professional workloads, building on GPT-5.4 with stronger reasoning, higher reliability, and improved token efficiency on hard tasks. It features a 1M+ token...

Use GPT-5.5 as a coding agent in your terminal

Start Darce in your project with GPT-5.5:

npm install -g darce-cli
darce --model openai/gpt-5.5

Already in a session? Type /model openai/gpt-5.5, or open the picker with Ctrl+P. Darce then reads your code, edits files and runs commands with GPT-5.5; risky commands ask first, and /undo reverses any change, including what shell commands did. No account yet? npx darce-cli lets you try it free. Which plan includes which models is on the pricing page.

Make it your default or a gear

In ~/.darcerc, set it as the starting model or add it to the gears you move between with Shift+↑ / Shift+↓ (see configuration):

{
  "router": { "default": "openai/gpt-5.5" },
  "gears": ["qwen/qwen3-coder", "openai/gpt-5.5"]
}

Compare it on your own code

Benchmarks rarely match your repository. Race GPT-5.5 against two other models on a real task and keep the best diff:

/derby --models openai/gpt-5.5,openai/gpt-6.1-sol,openai/gpt-6-sol fix the failing test

Read more about /derby and /swarm.

Related models

  • GPT-6.1 Sol (OpenAI): 1.05M tokens, $2.00 / $10.00 per 1M tokens
  • GPT-6 Sol (OpenAI): 1.05M tokens, $2.00 / $10.00 per 1M tokens
  • GPT-6 Luna (OpenAI): 1.05M tokens, $0.10 / $0.50 per 1M tokens
  • GPT-6 Astra (OpenAI): 1.05M tokens, $10.00 / $50.00 per 1M tokens
  • Claude Opus 5.5 (Anthropic): 1M tokens, $4.00 / $20.00 per 1M tokens
  • Claude Fable 5.1 (Anthropic): 1M tokens, $10.00 / $50.00 per 1M tokens
  • Claude Opus 5 (Anthropic): 1M tokens, $5.00 / $25.00 per 1M tokens
  • Qwen3.8 Max (0902) (Qwen (Alibaba)): 1M tokens, $2.00 / $6.00 per 1M tokens

All models · Getting started · Claude Code alternative

Model data from OpenRouter, refreshed daily. Prices are OpenRouter's list rates and show relative cost; your Darce allowance is used in proportion to them.