vibelab 0.0.1

Rigorous evaluation tool for comparing LLM coding agents

VibeLab

⚠️ ALPHA RELEASE - USE WITH CAUTION
This project is in alpha and under active development. Breaking changes are expected and will occur. Use at your own risk.

A rigorous evaluation tool for comparing LLM coding agents.

Overview

VibeLab helps software engineers evaluate and compare LLM coding agents (Claude Code, OpenAI Codex, Cursor, Gemini CLI) through controlled experiments. Instead of ad-hoc "vibe checks," get reproducible, comparable results across different agent configurations.

Features

• Comparative Runs: Test the same task across multiple agents side-by-side
• Datasets: Organize scenarios into collections for batch evaluation
• Result Tracking: Persistent storage of all runs with code diffs, logs, and metrics
• Human Feedback: Add notes and quality scores (Perfect/Good/Workable/Bad) to evaluate run fitness
• LLM Judges: Automatic graders that mimic human scores using few-shot examples
• Judgements: LLM-generated assessments with alignment scores showing judge-human correlation
• Web Dashboard: Visual comparison interface with diff viewer and dataset analytics
• Extensible: Add new agent harnesses by implementing a simple protocol

Installation

VibeLab can be run directly with uvx without installation:

# Run commands directly with uvx (no installation needed)
uvx vibelab start start-cmd

Or install it permanently:

# Install with uv
uv tool install vibelab

# Or with pip
pip install vibelab

Prerequisites

• Python 3.11+
• Git
• Agent CLIs you plan to use:

# Claude Code
npm install -g @anthropic-ai/claude-code

# OpenAI Codex
npm install -g @openai/codex

Quick Start

Run a comparison

# Compare Claude Code and Codex on the same task
uvx vibelab run run-cmd \
  --code github:owner/repo@main \
  --prompt "Add input validation to the login form" \
  --executor claude-code:anthropic:sonnet \
  --executor openai-codex:openai:gpt-4o

View results

# List recent results
uvx vibelab result list

# View a specific result
uvx vibelab result get <result-id>

# View the code diff
uvx vibelab result diff <result-id>

Launch the web UI

# Production mode (serves built frontend from package)
uvx vibelab start start-cmd

# Development mode (starts frontend dev server)
uvx vibelab start start-cmd --dev

CLI Reference

vibelab run

Execute a scenario against one or more executors.

uvx vibelab run run-cmd \
  --code <CODE_REF> \           # github:owner/repo@ref or local:/path
  --prompt <TEXT> \             # Task instructions
  --executor <SPEC> \           # harness:provider:model (repeatable)
  [--timeout <SECONDS>] \       # Default: 1800
  [--driver <DRIVER>]           # local (default), docker, modal

Options:

• --code: Repository reference. Formats:
  • github:owner/repo - Latest default branch
  • github:owner/repo@branch - Specific branch
  • github:owner/repo#commit - Specific commit
  • local:/path/to/repo - Local directory
• --prompt: Task instructions for the agent
• --executor: Agent specification as harness:provider:model (can be repeated)
• --timeout: Maximum execution time per agent in seconds (default: 1800)
• --driver: Execution driver: local, docker, or modal

vibelab scenario

Manage scenarios (code + prompt combinations).

uvx vibelab scenario create --code <REF> --prompt <TEXT>
uvx vibelab scenario list [--limit N]
uvx vibelab scenario get <ID>

vibelab dataset

Manage datasets (collections of scenarios for batch evaluation).

uvx vibelab dataset create --name <NAME> [--description <TEXT>]
uvx vibelab dataset list [--limit N]
uvx vibelab dataset get <ID>
uvx vibelab dataset delete <ID>
uvx vibelab dataset add-scenario --dataset <ID> --scenario <ID>
uvx vibelab dataset remove-scenario --dataset <ID> --scenario <ID>
uvx vibelab dataset run --dataset <ID> --executor <SPEC> [--trials N] [--minimal]

Options:

• --trials: Number of runs per scenario-executor pair (default: 1)
• --minimal: Only run scenario-executor pairs that don't have completed results
• --executor: Agent specification as harness:provider:model (can be repeated)

vibelab result

View and filter results, update notes and quality scores.

uvx vibelab result list [--scenario ID] [--executor SPEC] [--status STATUS]
uvx vibelab result get <ID>
uvx vibelab result diff <ID>
uvx vibelab result update-notes <ID> [--notes TEXT] [--clear]
uvx vibelab result update-quality <ID> [--quality 1-4] [--clear]
uvx vibelab result update <ID> [--notes TEXT] [--quality 1-4] [--clear-notes] [--clear-quality]

Filter options:

• --scenario: Filter by scenario ID
• --executor: Filter by executor spec (partial match)
• --status: Filter by status: queued, running, completed, failed, timeout

Update commands:

• update-notes: Add or update notes for a result. Use --notes "-" to read from stdin, or --clear to remove notes.
• update-quality: Set quality score (1=Bad, 2=Workable, 3=Good, 4=Perfect). Use --clear to remove score.
• update: Update both notes and quality in one command.

vibelab executor

List available agent configurations.

uvx vibelab executor list
uvx vibelab executor list --harness claude-code
uvx vibelab executor list --harness claude-code --provider anthropic

vibelab start

Launch the web server.

uvx vibelab start start-cmd [--port 8000] [--host 127.0.0.1] [--frontend-port 5173] [--dev/--no-dev]

Options:

• --port: Backend server port (default: 8000)
• --host: Backend server host (default: 127.0.0.1)
• --frontend-port: Frontend dev server port (default: 5173, only used with --dev)
• --dev/--no-dev: Development mode with frontend dev server, or production mode serving static files (default: --no-dev, production mode)

Configuration

VibeLab stores data in ~/.vibelab/ by default.

Environment Variables

Variable	Default	Description
VIBELAB_HOME	~/.vibelab	Data directory
VIBELAB_DRIVER	local	Default execution driver
VIBELAB_TIMEOUT	1800	Default timeout (seconds)
VIBELAB_LOG_LEVEL	INFO	Logging verbosity

API Keys

Configure API keys for the agents you want to use:

# Claude Code
export ANTHROPIC_API_KEY=sk-ant-...

# OpenAI Codex
export OPENAI_API_KEY=sk-...

# Cursor
export CURSOR_API_KEY=your-cursor-api-key

Supported Agents

Harness	Provider	Models
claude-code	anthropic	opus, sonnet, haiku
openai-codex	openai	gpt-4o, o3, o4-mini
cursor	cursor	composer-1

Data Layout

~/.vibelab/
├── data.db                    # SQLite database
└── results/
    └── {result_id}/
        ├── patch.diff         # Git patch of changes
        ├── stdout.log
        ├── stderr.log
        └── harness/           # Harness-specific artifacts
            └── trajectory.json

Web UI

The web interface provides:

• Dashboard: Recent scenarios and quick actions
• Scenarios: Table view of all scenarios with metrics
• Datasets: Collections of scenarios for batch evaluation
• Dataset Analytics: Matrix view showing scenario-executor status across all combinations
• Runs: Table view of all runs across scenarios with quality scores
• Executors: Single table view of all executor tuples (harness:provider:model) with filtering, selection, and quick run creation
• Run Creation: Form to configure and launch new comparisons
• Scenario Detail: Table view of all results for a scenario with comparison, judge management, and judgement display
• Compare Mode: Side-by-side comparison of two results
• Result Detail: Full diff viewer, logs, metrics, human notes/quality, and LLM judge judgements
• Judgements: Centralized view of all LLM judge assessments and pending judgements

Launch with:

uvx vibelab start start-cmd

Documentation

• SPEC.md - Product requirements
• PLAN.md - Implementation plan
• DEVELOPMENT.md - Development setup
• AGENTS.md - Instructions for AI coding agents

License

PolyForm Noncommercial 1.0.0 - Free to use for personal and non-commercial purposes. Commercial use and resale are not permitted.