Janus Labs

3DMark for AI Agents. Profile AI coding agents across two active axes: Code Quality and Error Resilience. Measure Instruction Resilience separately with janus-labs diagnose when you have configured and vanilla results to compare.

What Janus Labs Does

Janus Labs benchmarks real coding-agent behavior on reproducible tasks. Instead of reducing everything to one opaque number, it runs a fixed suite of coding tasks and produces a capability profile that shows where an agent is strong, weak, or uneven.

• refactor-storm ships 4 built-in behaviors grouped into 2 active axes
• janus-labs run is the primary workflow for generating a full suite result
• Backend-hosted judging is available without a local API key, and --mock supports offline dry runs
• Results can be compared against bundled baselines and submitted to a public leaderboard

Public leaderboard: https://fulfilling-courtesy-production-9c2c.up.railway.app

Quick Start

1. Install

pip install janus-labs
janus-labs doctor

doctor checks Python version, dependencies, which agent CLIs are on your PATH, and API keys. On Windows, use python -m janus_labs if janus-labs is not in PATH.

2. Benchmark Your Agent

The primary workflow: run the full suite with your agent, then submit.

# Benchmark Codex (or claude, gemini, copilot)
janus-labs run --full --agent codex --suite refactor-storm -o result.json

# Custom agent command (any CLI that accepts a prompt)
janus-labs run --full --agent-cmd "my-agent --prompt {prompt_file}" --suite refactor-storm -o result.json

# Submit to the public leaderboard
janus-labs submit result.json --github your-handle

This initializes 4 behavior workspaces, runs your agent on each, scores the outcomes, and produces a single result file. Built-in agent presets: codex, claude, gemini, copilot.

3. Try It Without an Agent

Don't have an agent CLI handy? Use mock or backend-hosted scoring to explore the pipeline:

# Offline mock scoring (instant, deterministic, no API key)
janus-labs run --suite refactor-storm --mock -o result.json

# Backend-hosted judging (no local API key needed)
janus-labs run --suite refactor-storm -o result.json

# Suite alias shortcut
janus-labs refactor-storm -o result.json

These modes score the unmodified scaffold code and are useful for testing the pipeline, CI setup, or exploring the output format.

4. Compare and Profile

# Compare your result against an auto-selected vanilla baseline
janus-labs compare result.json --auto-baseline

# Generate capability profiles from bundled baseline results
janus-labs profile --baselines-dir data/baselines

# Measure optional instruction resilience (needs configured + vanilla results)
janus-labs diagnose result.json

Alternative: Single-Behavior Manual Workflow

Use init -> status -> score when you want to hand a single behavior workspace to an external agent and inspect the repo diff yourself.

janus-labs init --suite refactor-storm --output ./janus-task
cd janus-task/BHV-001-test-cheating
# ... let your agent work ...
janus-labs score --workspace . --output result.json

Install From Source

git clone https://github.com/alexanderaperry-arch/janus-labs.git
cd janus-labs
python -m venv .venv
source .venv/bin/activate  # Windows: .venv\Scripts\activate
pip install -e .

CLI Reference

All commands can be run as:

• janus-labs <command>
• janus <command>
• python -m janus_labs <command>

Global

janus-labs --help
janus-labs --version
janus-labs

Running janus-labs with no arguments opens the interactive menu.

run

Run an end-to-end suite directly.

janus-labs run --suite refactor-storm --mock -o result.json
janus-labs run --suite refactor-storm -o result.json
janus-labs refactor-storm -o result.json

Options:

• --full: run the full init -> agent -> score -> output pipeline (the primary workflow)
• --agent: built-in agent preset (codex, claude, gemini, copilot). Requires --full
• --agent-cmd: custom agent command template. Use {prompt_file} for file path or {prompt_content} for inline prompt. Requires --full
• --timeout: agent timeout in seconds per behavior (default: 300)
• --suite: suite ID, required
• --output, -o: output file, default result.json
• --format: json, html, or both
• --mock: use deterministic offline scoring (no agent needed)
• --judge: use local LLM-as-judge scoring
• --model: judge model, default gpt-4o
• --no-interactive: disable prompts on backend rate limits
• --request-delay: delay between judge requests

init

Initialize workspaces for every behavior in a suite.

janus-labs init --suite refactor-storm --output ./janus-task

Options:

• --suite: suite ID, default refactor-storm
• --output, -o: output directory for generated behavior workspaces

status

Inspect a task workspace and get the recommended next step.

janus-labs status --workspace ./janus-task/BHV-001-test-cheating

score

Score one completed task workspace.

janus-labs score --workspace ./janus-task/BHV-001-test-cheating --output result.json

Options:

• --workspace, -w: workspace path, default current directory
• --output, -o: output file, default result.json
• --judge: enable LLM-as-judge scoring
• --model: judge model, default gpt-4o
• --bundle: optional bundle file for judge scoring
• --agent: override detected agent identifier
• --agent-model: override detected agent model

submit

Submit a scored result to the public leaderboard.

janus-labs submit result.json --github your-handle

Options:

• --dry-run: print the payload without submitting
• --github: GitHub handle for attribution
• --no-judge: skip backend LLM judging during submission
• --no-open: skip opening the share URL in a browser (useful in CI)

compare

Detect regressions between two results, or compare a result against a precomputed vanilla baseline.

janus-labs compare baseline.json current.json
janus-labs compare result.json --auto-baseline

profile

Generate capability profiles from one baseline file or a directory of baselines.

janus-labs profile --baseline data/baselines/baseline.json
janus-labs profile --baselines-dir data/baselines
janus-labs profile --baselines-dir data/baselines --json
janus-labs profile --leaderboard
janus-labs profile --reliability

diagnose

Measure optional instruction resilience by comparing configured results against vanilla baselines.

janus-labs diagnose result.json

smoke-test

Quick validation path using mock data. This does not benchmark your real config.

janus-labs smoke-test --suite refactor-storm

baseline

Inspect or update baseline files.

janus-labs baseline list
janus-labs baseline show baseline.json
janus-labs baseline update result.json -o baseline.json

Built-In Suite

Refactor Storm (v2.0.0)

refactor-storm ships 4 built-in behaviors grouped into 2 active axes:

• BHV-001 Test Cheating Detection -> Code Quality
• BHV-002 Reduce Cyclomatic Complexity -> Code Quality
• BHV-003 Add Comprehensive Error Handling -> Error Resilience
• BHV-004 Loop Detection Compliance -> Error Resilience

Composite score = avg(Code Quality, Error Resilience).

janus-labs diagnose can compute optional Instruction Resilience separately by comparing configured runs against vanilla baselines. It is not part of the 2-axis composite.

GitHub Actions

- name: Install Janus Labs
  run: pip install janus-labs

- name: Run mock suite
  run: janus-labs run --suite refactor-storm --mock --no-interactive -o current.json

- name: Compare to baseline
  run: janus-labs compare baseline.json current.json --format github

Requirements

• Python 3.12+
• Core dependencies include DeepEval, GitPython, PyYAML, and Pydantic

Phoenix telemetry is optional and requires Python <3.14:

pip install -r requirements-phoenix.txt

Contributing

See CONTRIBUTING.md.

License

Apache 2.0. See LICENSE.