OB-1
Free coding agent that fixes code and verifies it works, no setup required
What is Ob 1?
OB-1 is a free, open-source coding agent that runs in your terminal to edit code and verify its own work. It requires no account, API key, or credit card to start—just install and begin. The agent automatically runs your project's test suite after each change and self-corrects until all checks pass, combining multi-agent reasoning with context-efficient routing to support both free and paid models.
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Key Features of Ob 1
- Self-checking code verification
- Multi-agent parallel investigation
- Project memory and context awareness
- Automatic test suite integration
- Rewind/undo functionality
- Free model router with 30-day new model access
- Repository context mapping
- Automatic context compaction
- No account or API key required
- Apache-2.0 open source
Who Should Use Ob 1?
Fix failing unit tests automatically
Debug flaky tests with parallel investigation
Refactor code with verification
Implement features with test-driven validation
Experiment safely with rewind capability
Maintain project context across sessions
Ob 1: Pros & Cons
✓Pros
- Completely free to start with no trial period
- No surprise billing or overage charges
- Works offline with local models
- Multi-agent reasoning for complex problems
- Automatic self-correction until tests pass
- Open source and auditable
- One-command undo for safe experimentation
- Token-efficient context management
- Built-in test suite integration
✕Cons
- Requires macOS or Linux (no Windows support mentioned)
- New free models available to free users only after 30-day delay
Frequently Asked Questions about Ob 1
Do I need an API key or account to use OB-1?
No. OB-1 is free out of the box with no account, card, or API key required. Install it and start immediately.
How does OB-1 verify its work?
After every file change, OB-1 runs your project's test suite and checks automatically. It self-corrects until all checks pass.
What operating systems does OB-1 support?
OB-1 runs on macOS and Linux. Windows is not supported.
Can I undo changes made by OB-1?
Yes. The /rewind command restores your files and conversation to any earlier point in the session.
How are free vs. paid models accessed?
The free tier uses a built-in free-models router with no account needed. New free models reach free users after 30 days; paid plans get immediate access to all models.
Tool Details
- Company
- Overbrilliant
- Pricing
- Free
- Category
- Ai Vscode Assistant
- Added
- Jul 2026
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