Pydantic Evals
The facts below are what the maker publishes about Pydantic Evals, checked and dated. Our editors have not written about it yet.
The facts
Each one read from Pydantic Evals's own pages, with the date it was checked.
What it does
- Agent behavior checks
- Built-in evaluator examples cover tool correctness, trajectory matching, argument correctness, maximum tool calls, and maximum model requests.checked 29 Sep 2026
- Code-first workflow
- Evaluation components are defined in Python, and experiment reports can be printed, serialized, or viewed in Pydantic Logfire.checked 30 Sep 2026
- Datasets and cases
- Datasets group test cases, which can include inputs, expected outputs, metadata, and case-specific evaluators.checked 30 Sep 2026
- Dependencies
- Pydantic Evals does not depend on pydantic-ai, and Logfire is optional.checked 29 Sep 2026
- Evaluators
- It includes built-in deterministic evaluators and supports custom evaluators, LLM judges, and evaluators that return assertions, scores, or labels.checked 29 Sep 2026
- Evaluator types
- Evaluators include deterministic checks, LLM judges, span-based and agentic evaluators, and custom evaluators.checked 30 Sep 2026
- Installation
- The package installs with `pip install pydantic-evals` or `uv add pydantic-evals`.checked 30 Sep 2026
- Logfire integration
- Logfire is an optional dependency for using OpenTelemetry traces in evaluations or sending evaluation results to Logfire.checked 30 Sep 2026
- Online evaluation
- Evaluators can run in the background on every production or staging call, or on a sampled subset of traffic.checked 30 Sep 2026
- Production evaluation
- Online evaluation can attach evaluators to production or staging traffic so every call or a sampled subset is graded in the background.checked 29 Sep 2026
- Purpose
- Pydantic Evals tests and evaluates AI systems, from simple LLM calls to complex multi-agent applications.checked 30 Sep 2026
- Related service security
- Pydantic says Logfire is SOC 2 Type 2 audited, GDPR aligned, and can support HIPAA workloads under a signed Business Associate Agreement.checked 30 Sep 2026
- Security
- Pydantic’s Logfire security page states that it has SOC 2 Type 2 audited controls, GDPR compliance, and HIPAA support under a signed Business Associate Agreement.checked 29 Sep 2026
- Third-party integrations
- The documentation shows adapters for Ragas and DeepEval, which are optional dependencies and are not installed with Pydantic Evals.checked 30 Sep 2026
- What it evaluates
- It can grade an agent’s final outputs and tool-call trajectory against datasets or sampled live production traffic.checked 30 Sep 2026
Money
- Cost consideration
- LLM-as-a-judge evaluations can take seconds, cost money, and produce non-deterministic results; deterministic evaluators are described as having no cost.checked 29 Sep 2026
- Costs and tradeoffs
- LLM judges can be slower, cost money, be non-deterministic, and have biases.checked 30 Sep 2026
The company
- Maker
- Pydantic describes itself as a remote-first company.checked 30 Sep 2026
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