Chemin

Know what improvement looks like before training

A model can score well on a benchmark while still missing the cases that matter to your team. Chemin builds evaluation suites around your use cases, so you can compare checkpoints against consistent criteria before deployment.

Know what improvement looks like before training

Evaluation suites

Evaluate model performance against your chosen criteria, with expert-designed rubrics, safety testing, and regression checks across model updates.

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The data problems that can weaken RL programs

A reward signal is only as good as the data behind it — noise in evaluation or preference data optimizes a model in the wrong direction, quietly and for months.
Evaluations miss important cases

Evaluations miss important cases

Public benchmarks may not reflect the inputs and edge cases your model encounters in production. 

Verifiers cover too little

Verifiers cover too little

A verifier built for narrow cases can miss valid answers or reward incorrect ones.

Preference labels vary

Preference labels vary

When reviewers interpret quality differently, those differences can affect the reward signal. 

Data generation from source to success

Data generation from source to success

End-to-end data services from sourcing and annotation to data generation for model training

100M+

data points transformed

30,000+

data operations team members

18

countries in our global network

Why Chemin

Chemin evaluates tasks, verifiers, and expert preference data into one work stream, with criteria your team can trust.

Why Chemin

Evaluation

The goal is to know what better means before optimizing for it. We build custom evaluation suites around your production distribution instead of public benchmarks, with rubrics designed alongside your domain specialists. We also run red teaming and safety evaluation to catch adversarial behavior, and we tie regression evals directly into your retraining cycle so they run continuously rather than once.

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Frequently asked questions

Find answers to common questions about our services, process, and how we can support your needs.

What is the difference between RLVR and RLHF?

RLHF uses human feedback to guide training. RLVR uses reward signals from verifiers that check defined outcomes, such as passing code tests or satisfying a mathematical check. 

Can RLHF and RLVR be used together?

Yes. A program can use human feedback for subjective criteria and verifiers for outcomes that can be checked automatically.

Can Chemin build custom evaluation suites?

Yes. Evaluation tasks, rubrics, safety checks, and regression tests can be scoped around your model requirements and use cases.

How do you review the quality of response reviews?

Clear rubrics, reviewer calibration, and annotator agreement tracking make differences in judgment visible and help teams review feedback quality.

Does every AI application need reinforcement learning?

No. The right approach depends on the model, its objectives, and whether its behavior needs to be refined through feedback or optimization.

How do you know if a model has improved?

Compare checkpoints against consistent task-specific evaluation criteria and check for regressions before deployment.

Make model progress easier to measure

Build an evaluation and feedback pipeline around the work your model needs to handle.

Reinforcement Learning: Evals, RLVR, and RLHF | Chemin