OpenCode + Go: An Open-Source Coding Agent at $10/Month

What OpenCode Is

OpenCode is an open source AI coding agent. It runs in your terminal, as a desktop app, or as an IDE extension. The company behind it is Anomaly (anoma.ly). The license is MIT. The source is on GitHub.

As of September 17, 2026, the repo has 207,928 stars and 27,306 forks. The latest release is v1.18.31.

It works with any model provider. You bring your own API key, or you subscribe to OpenCode Go.

Install

On Windows:

choco install opencode

On macOS or Linux:

curl -fsSL https://opencode.ai/install | bash

With Node.js:

npm install -g opencode-ai

Start a Project

1. Open your project folder in a terminal.
2. Run opencode.
3. Run /init. This creates an AGENTS.md file. The agent reads it to learn your project structure and coding patterns.

Disclosure: Affiliate link. The Go link in this article contains my referral code. When a new user subscribes through it, both of us get $5 credit. OpenCode runs this referral program for its own users. There is no ongoing commission. You can also subscribe directly at opencode.ai/go.

Plan Mode vs Build Mode

Press Tab to switch between the two modes.

In Plan mode, OpenCode suggests how it will build a feature. It does not edit your files. You review the plan. You can add details and drop images into the terminal as references.

In Build mode, OpenCode makes the changes. After each change, run /undo to revert it or /redo to repeat it.

OpenCode Go

OpenCode Go is a $10/month subscription. It gives you access to 28 open and open-weight models through one API key. The models are tested by the OpenCode team for agent work.

The lineup includes Kimi K3, GLM-5.3, MiniMax M3, GPT 5.6 Luna, Qwen3.7 Plus, DeepSeek V4, Grok 4.6, and MiMo-V2.5. The list changes as OpenCode tests new models.

Go is a provider inside OpenCode, not a lock-in. You can use any other provider at the same time.

Usage Limits

Each model has a monthly dollar cap. The 5-hour limit is 20% of the monthly cap. The weekly limit is 50%.

Pick a model and a budget:

DeepSeek V4 Flash uses peak/off-peak pricing. Peak hours are 01:00–04:00 and 06:00–10:00 UTC on weekdays.

The request estimates use a fixed token profile per request. Your numbers will vary.

Referral Program

OpenCode Go has a referral program. When a friend subscribes through your link, both of you get $5 credit. There is no tier system. OpenCode announces the program on X and in the community.

Data and Privacy

Read this before you pick a model:

• Muse Spark 1.3 / 1.2 Contributor. Your prompts and completions train Meta models. You get a low price in return. Availability is limited to regions that Meta's policy allows.
• Grok 4.6 (ZDR option). Zero data retention turns off the stateful Responses API, Files, Collections, and Batch API.
• DeepSeek (ZDR option). The zero data retention agreement renews monthly. The current one runs through September 30, 2026.

If you need full zero data retention, pick the DeepSeek or Grok rows with ZDR. If cost is the only concern, the Muse rows are cheapest.

Where It Loses to Claude Code, Codex, and Cursor

OpenCode is a thin, fast, model-agnostic agent. The trade-off:

• No frontier closed model. Go has no Claude Opus, no GPT-6 Astra, no Gemini 3.8 Pro. If you need the top proprietary model, use Claude Code, Codex, or the API directly.
• Young project. The install, undo/redo, and session features work. The agent is less battle-tested than a year of Claude Code or Codex.
• Terminal-first. There is a desktop app and IDE extensions, but the UX is built around the terminal.

For everyday coding on open models at $10/month, Go is the cheapest reliable option in this article. For hard reasoning tasks, pair it with a frontier model provider.

Quick Start

choco install opencode
opencode
/init

Then subscribe to Go, run /connect, pick OpenCode Go, and paste your API key.

Sources

• OpenCode docs: opencode.ai/docs
• OpenCode Go docs: opencode.ai/docs/go
• GitHub repo: anomalyco/opencode
• Anomaly (company): anoma.ly
• Go referral program: OpenCode's X post and the r/opencode referral thread
• Terms: opencode.ai/legal/terms-of-service

All numbers verified against the official docs on September 17, 2026.