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Getting started

The quickstart below uses pydantic-evals. If you are new to it, start here. If you write your evals in DeepEval, Eval runners goes through the same steps with a DeepEval run.

1. Install

# The quick start uses pydantic-evals as the eval runner and evaluates an agent built in pydantic-ai, but neither is required for evaltrack.
uv add "evaltrack[ui,pydantic-evals]" "pydantic-ai-slim[openai]"
# or
pip install "evaltrack[ui,pydantic-evals]" "pydantic-ai-slim[openai]"

Note

Linux and macOS are supported, on Python 3.11 to 3.14. If your machine runs Windows, run evaltrack under WSL2.

2. Write a tracked eval

Add @pytest.mark.evaltrack to a test and hand the eval to evaltrack.run(). The test below is sync. For an async test, use await evaltrack.run_async(dataset.evaluate, task) with your async plugin.

import pytest
from pydantic_ai import Agent
from pydantic_evals import Case, Dataset
from pydantic_evals.evaluators import LLMJudge

import evaltrack


@pytest.mark.evaltrack(score_bars={"helpfulness": 0.8}, flake_reruns=2)
def test_support_agent() -> None:
    agent = Agent(
        "openai:gpt-4o-mini",
        instructions=(
            "Support the Snapwombat photo app. Deleted photos are restorable from "
            "Settings > Backups for 30 days. Never promise or rule out a refund. Send "
            "billing questions to support@snapwombat.example."
        ),
    )

    async def support_task(prompt: str) -> str:
        return (await agent.run(prompt)).output

    dataset = Dataset(
        name="snapwombat-support",
        cases=[
            Case(name="refund-demand", inputs="The app deleted my photos. I want my money back!"),
            Case(name="restore-backup", inputs="How do I restore a backup?"),
        ],
        evaluators=[
            # An assertion: must be true, or the case fails.
            LLMJudge(rubric="The reply neither promises nor rules out a refund", include_input=True),
            # A score, gated at 0.8 by the marker's score bar.
            LLMJudge(
                rubric=(
                    "Rate how helpful and clear the reply is, from 0.0 to 1.0. "
                    "Declining to promise a refund is not unhelpful."
                ),
                include_input=True,
                score={"evaluation_name": "helpfulness", "include_reason": True},
                assertion=False,
            ),
        ],
    )

    # The marker gates here: a failed assertion, or a score under 0.8, fails the test.
    # `flake_reruns=2` runs the eval again while a case is failing, up to twice.
    evaltrack.run(dataset.evaluate_sync, support_task)

The agent and the two LLM judges all call a real model, so this test needs an API key (here OPENAI_API_KEY). The examples run without one — test_05_llm_judge.py is the same pattern, an LLMJudge guardrail plus a score_bars-gated score, with the model and the judge scripted.

One test is one eval

One test needs to be one eval. evaltrack records one eval per test, whichever runner produced it, and the test's name identifies that eval everywhere. If you want two evals, write two tests.

3. Run it

evaltrack is a registered pytest marker. You can select only your evals:

pytest -m "evaltrack"

Each pytest session produces a run, a snapshot of all recorded eval results, saved to .evaltrack/ by default (add .evaltrack/ to your project's .gitignore).

CI can run the same command. See CI/CD.

4. See the results

evaltrack ui

This serves the dashboard at http://127.0.0.1:8765 and prints the link. Browse scores and pass-rates per case, and diff any two runs. Open a case to see each score against its bar and its history over the mainline.

Note

The dashboard's React frontend is beta, written largely by AI coding agents. The security notes are in the security policy.

5. Track a shared remote (optional)

Declare your repositories in pyproject.toml. local is where the plugin saves runs. remote is a shared repository that your CI writes to (Azure Blob Storage or Amazon S3). It stores the baseline (the run recorded for what is currently deployed) and the PR history.

[tool.evaltrack]
local  = "./.evaltrack"
remote = "azure://account/evals"

evaltrack ui then mounts both and opens on your latest local run. Click Compare to mainline to diff your run against the baseline run, the one recorded for what is deployed. See Repositories and storage for the full setup.

Related: The evaltrack marker · Eval runners · CI/CD