Know what your agent does before you release it.

Versalist helps developers test AI agents, inspect failures, and compare changes before release.

  1. 1. Challengeexample challengeillustrative
  2. 2. Runsexample runillustrative
  3. 3. Scoreexample rubricillustrative
  4. 4. Releaseexample releaseillustrative
illustrative workflow
Follow a complete example in the docs

How agent evaluation works

Challenge

Task and test cases

Task details, evaluation cases, and scoring rules stay attached to the challenge.

Run trace

Recorded call history

When enabled, capture records metadata for agent turns, agent model calls, and judge calls.

Evaluation

Scores by dimension

Read each scoring dimension to see which checks passed and which need attention.

Skill changes

Versioned instructions

Compare instruction changes against the current version before you release them.

OpenAIAnthropicMetaGooglexAIQwenMCPLocal commandsOpenAIAnthropicMetaGooglexAIQwenMCPLocal commands

Use your existing workspace

Bring your own coding agent.

Open your agent guide. Then connect the Versalist CLI or MCP server from the same repository and terminal.

A repeatable task with clear checks.

A challenge keeps the task, test cases, and scoring rules together.

01

Brief

Task, constraints, and expected behavior.

02

Cases

Versioned evaluation inputs and expected behavior.

03

Scoring rules

Criteria for checking the output.

04

Run details

Recorded calls for inspection when trace capture is enabled.

Inspect the failed check.

Each CLI run records its command, output, duration, source revision, and challenge hash. Hosted runs can also store authorized call metadata.

Check the result before release.

Use the same tests for both versions. The CLI returns a failing status when a candidate fails its checks or comparison threshold.

Keep the change and its evidence.

You can turn accepted improvements into versioned, reusable skills. The evidence remains available for later review.

TestUnderstandCompareRelease.

The same workflow you already use for code, applied to agent behavior.

Test the agent

Pick a challenge: a fixed task with inputs, expected results, and a weighted rubric. Run your agent against it from the web app or from the terminal it already uses.

Understand the failures

Read the available output and evaluation results. Separate failed checks from execution errors. Authorized trace capture adds call metadata.

Compare, then release

Save a failure as a test case, change the instructions, and evaluate baseline and candidate on the same cases. Keep the change only when the evidence supports it.

Run Versalist from the same terminal your agent already uses

One command pulls the challenge into your repo. Test a candidate, read the failed checks, and compare it with your recorded baseline before you release it.

Try it now
npx -y @versalist/cli start agentic-code-optimization-review
No install required. versalist list works without an account; start and submit need a free API key (VERSALIST_API_KEY).
1

Start

Pull the challenge brief, public test cases, and expected results into the repo your agent is already using.

2

Run

Run the agent from the CLI. Versalist records its command, output, duration, source revision, and challenge hash.

3

Evaluate

Run a verifier. A passing check records a score of 100; a failing check records 0 and exits nonzero, with the logs next to the run.

4

Compare

Compare a candidate with the baseline. The result is improved, unchanged, below_threshold, or regressed, and the CLI fails on the last two.

5

Submit

Review the local evidence. Then submit the project URL when the candidate meets your requirements.

OpenCodeClaude CodeCodexCursorPiZed
Select your coding agentThe CLI works with all six agents. Five agents can start the package in MCP mode. Pi uses the CLI path because it does not include native MCP support.
Terminal Workflow
$versalist start agentic-code-optimization-review

[ok] Wrote CHALLENGE.md

[ok] Wrote .versalist.json

[info] Challenge context is ready

$versalist run --command "python agent.py"

[ok] Agent run and provenance recorded

$versalist evaluate --run latest --command "pytest"

[ok] Verifier result recorded

[info] Compare this candidate with the baseline

$

Frequently Asked Questions

Versalist helps developers test AI agents, inspect failures, and compare changes before release.