Gemini 3.1 Pro Preview as a coding agent in your terminal

Strengths

Google's Gemini Pro model with a 1M token context. Good at reading large codebases and long documents; one of Darce's default /derby contestants.

OpenRouter's description:

Gemini 3.1 Pro Preview is Google’s frontier reasoning model, delivering enhanced software engineering performance, improved agentic reliability, and more efficient token usage across complex workflows. Building on the multimodal foundation...

Use Gemini 3.1 Pro Preview as a coding agent in your terminal

Start Darce in your project with Gemini 3.1 Pro Preview:

npm install -g darce-cli
darce --model google/gemini-3.1-pro-preview

Already in a session? Type /model google/gemini-3.1-pro-preview, or open the picker with Ctrl+P. Darce then reads your code, edits files and runs commands with Gemini 3.1 Pro Preview; 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": "google/gemini-3.1-pro-preview" },
  "gears": ["qwen/qwen3-coder", "google/gemini-3.1-pro-preview"]
}

Compare it on your own code

Benchmarks rarely match your repository. Race Gemini 3.1 Pro Preview against two other models on a real task and keep the best diff:

/derby --models google/gemini-3.1-pro-preview,google/gemini-3.8-flash,google/gemini-3.5-flash-lite fix the failing test

Read more about /derby and /swarm.

Related models

• Gemini 3.8 Flash (Google): 1.05M tokens, $0.75 / $3.75 per 1M tokens
• Gemini 3.5 Flash Lite (Google): 1.05M tokens, $0.30 / $2.50 per 1M tokens
• Gemma 4 31B (Google): 262k tokens, $0.090 / $0.34 per 1M tokens
• Claude Sonnet 5.5 (Anthropic): 1M tokens, $2.00 / $10.00 per 1M tokens
• Claude Sonnet 4.5 (Anthropic): 1M tokens, $3.00 / $15.00 per 1M tokens
• GPT-6.1 Sol (OpenAI): 1.05M tokens, $2.00 / $10.00 per 1M tokens
• GPT-5.6 Sol (OpenAI): 1.05M tokens, $2.00 / $10.00 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.