Why an Experiment exists
Evaluation has many variables you can set. You can give each Task one attempt or several, change the decoding temperature, run a different subset of the tasks, or mark answers more or less strictly. Each of those returns a different number for the same model, and none of them is wrong. They answer different questions about how well the model does the task. An Experiment holds those variables constant, so within one Experiment the model is the only thing that changed between two Runs. You can define as many Experiments as you want. When the variables go unrecorded, old results stop being usable. You cannot tell why two numbers differ, so you cannot compare the experiments that produced them.What an Experiment fixes
An Experiment fixes three things when you create it.- The tasks. Which tasks run, as an exact list. Not a count and not a name, but those specific tasks.
- The eval settings. How the model is sampled: the decoding, the temperature, and how many attempts each Task gets.
- The grading. Which grader scores the answers, and the prompt the model saw.
The Splits
An Experiment owns its Splits, and the trainer and the evaluator both read the same lists, which is what holds the roles below in place. An Experiment over a trainable Environment carries all three. One over an eval-only Environment carriesdev alone when that Environment was frozen from a single benchmark, and dev and test when it was frozen from two, which is the form that can carry a final claim.
train. What the model learns on.dev. What the driving agent reads to choose its next Move.test. Held back for the Baseline and the final claim.
dev shows, so the loop fits itself to those tasks over time. A dev score therefore overstates the model, which is why dev is not the number you report. test stays out of the loop entirely, and it gets two reads: you take the first one yourself, as a deliberate eval of the base model before any training begins, and the second is the final claim, after which Monte refuses a third. Skip that first read and Monte refuses the claim as well, because there would be nothing to compare it against. Improvement covers how those reads happen.
Related pages
Environments
The graded world an Experiment freezes.
Improvement
How Splits, Baselines, and deltas judge improvement.
Glossary
The record every Run writes to.

