The Prove route (optional)

Prove is one of the two routes a generated task can be run down, beside verifiers. It is an optional route, not a dependency: a plain install of Poisson Tasks does not bring it, and nothing in the README’s first run, in poisson-tasks or in the verifiers export needs it. Prove is public on PyPI as poisson-prove, and Poisson Tasks asks for it through an extra, prove.

poisson_tasks.adapter is the only module that needs Prove. Without Prove installed, import poisson_tasks and every module under it work as they do with it, and importing the adapter raises a ModuleNotFoundError that names the extra. The tests that need Prove are skipped without it, and say so.

Install it beside Tasks

pip install "poisson-tasks[prove]"

The extra installs poisson-prove 0.1.0 or later, with no upper bound. The route is checked from both sides: every release of Tasks is run end to end against the Prove that PyPI serves, and 0.1.0, 0.1.1, 0.1.2 and 0.1.3 each passed; every pull request and release of Prove runs the same check, from the latest release of Tasks, before it ships. The command it adds is poisson-prove (python -m poisson_prove is the same).

From a checkout of this repository, the extra is installed with the development tools:

.venv/bin/pip install -e ".[dev,prove]"

The scripted path, end to end

.venv/bin/python examples/prove_sweep/run.py

The example writes a pre-registration, builds a registry module from it under its own hash, writes a Prove sweep spec, and runs three real poisson-prove sweep processes, one per arm, driven by the reference policy: the one that plays each task correctly. It then reads the stored episodes back and prints their outcomes, and runs a poisson-prove diff of the two depth arms. Every episode comes back passed, and the depth arms differ in turns: 2 at d1, 4 at d3. The example reads the diff from --json, where truncated is 0, which is the registration’s horizon cutting no arm short. That is the point of the scripted path: the instrument is exercised with the model taken out, so a later failure is a model’s and not the instrument’s.

It takes a few seconds and writes about 80 KB under examples/prove_sweep/example-store, which git ignores. Delete that folder to start over. The example is source to read; python.md lists the others.

What a release checks

scripts/release/prove_e2e.py is the same route from nothing but two published packages: it takes the wheel built from the tree, makes a fresh environment, installs the wheel with its prove extra so that poisson-prove comes from PyPI, runs the example and the real poisson-prove command on the built-in tasks, reads the episodes back, and then uninstalls Prove and checks that Tasks still imports and that the adapter is refused with the extra’s name. Every release runs it (releasing.md), and so does the fast lane of the pull request check.

Registrations, and the horizon

A study run down this route is registered before it runs: which levels of a knob it sweeps is written down in advance, and is not a property of the generator. poisson_tasks.adapter.validate_preregistration checks a registration, and takes depth and the decoy-tools dial only. A sweep of a knob without its control arm is refused, rather than letting the study run.

A registration’s horizon is the largest max_turns over its arms (spec.max_turns(slack), knobs-and-arms.md), and it is checked rather than declared: validate_preregistration recomputes it and refuses a document that states a different number. The horizon is what Prove uses to cut an episode short, so a wrong one would silently truncate the deepest arm.