KitchenBench

A bimanual kitchen-manipulation benchmark for VLA models.

Built on Inspect Robots · part of WorldEvals, the "Inspect Evals for robotics".

Note

This project is in early development. The API may change between releases, so pin a version before depending on it.

KitchenBench is 10 kitchen-manipulation tasks expressed as Inspect Robots Tasks. They are embodiment-agnostic, so you run them against any compatible policy/embodiment. The set emphasizes bimanual coordination: pouring, lid removal, folding, part-mating, a pure two-arm handover, and tool-mediated scooping, alongside classic pick-place / stacking / slotted insertion and a multi-instance sort.

It ships a dependency-free mock kitchen so the whole suite runs in CI, and is designed to point straight at real hardware (e.g. YAM bimanual arms driven by MolmoAct2).

The tasks

Task (--task)	Goal	Bimanual	Category
kitchenbench/place_cutlery	place the {cutlery} on the {dishware}		pick-place
kitchenbench/stack	stack the cups / bowls / plates		stacking
kitchenbench/place_in_rack	place the {dishware} into the dish rack		insertion
kitchenbench/pour_pasta	pour the dry pasta into the {vessel}	✅	granular
kitchenbench/open_container	open the {container}	✅	articulated
kitchenbench/fold_cloth	fold the {cloth}	✅	deformable
kitchenbench/seal_container	seal the {container} with its lid	✅	mating
kitchenbench/handoff	hand off the {item} from one arm to the other	✅	coordination
kitchenbench/sort_cutlery	sort the cutlery into the correct tray compartments		classification
kitchenbench/scoop_pasta	scoop about {fill_target_g} g of the {pasta} with the {tool} and transfer it to the container	✅	granular+tool

Note

KitchenBench-Lite: place_cutlery, stack, place_in_rack, open_container, and scoop_pasta together form KitchenBench-Lite, a five-task subset of the full benchmark.

Note

Every value each task varies over (the objects a {placeholder} can name, counts, forces, placement jitter) is documented in the task reference on the KitchenBench docs site. The per-instance distributions live in specs.py.

Quick start

Install from PyPI (uv shown, plain pip works too; inspect-robots comes along as a dependency):

uv pip install kitchenbench

Installing registers the 10 tasks plus a dependency-free mock kitchen (the kitchen embodiment and the kitchen_scripted / kitchen_random / kitchen_noop policies) with Inspect Robots via entry points, so everything below runs immediately: no hardware, no simulator, no configuration.

Run one task (5 instances × 5 realizations = 25 rollouts, a few seconds on the mock):

inspect-robots list tasks    # the 10 kitchenbench/* tasks from the table above
inspect-robots run --task kitchenbench/pour_pasta --policy kitchen_scripted --embodiment kitchen

Run the whole benchmark from Python with eval_set:

from inspect_robots import eval_set

from kitchenbench import TASK_FACTORIES

ok, logs = eval_set(
    [f"kitchenbench/{key}" for key in sorted(TASK_FACTORIES)],
    "kitchen_scripted",
    "kitchen",
)
for log in logs:
    print(log.eval.task, log.results.metrics["task_success"])

The mock is abstract (it models progress toward the scene goal, like Inspect Robots's CubePick). Its job is to exercise the pipeline and give you a template. In the mock, success depends only on the seeded goal direction, so the sampled setup distributions have no causal effect (P̂ is degenerately 1.0 for the scripted oracle); the distribution content only bites on a real embodiment. The value is the task definitions, which run unchanged on a real robot: to evaluate a real VLA, swap in a real policy/embodiment pair (see "Run it on real hardware" and "Run it in simulation" below).

Task instances & realizations

KitchenBench follows the physical-automation methodology. The key ideas, top-down:

• A task (e.g. pour_pasta) is a set of task instances.
• A task instance is one concrete scenario written as a distribution: a stochastic setup (named random variables, each with a distribution) plus a goal (a natural-language success criterion that may reference the sampled variables). It is not a single fixed scene. It is a recipe for generating many.
• A realization is one sample of that recipe: draw every random variable from its distribution to get one concrete environment (and a concrete goal sentence).
• Running a (policy, embodiment) pair on K_realizations realizations and averaging the binary successes estimates the instance success probability P̂[Yᵢ = 1].

task  pour_pasta
 ├─ instance 1  (a distribution)  ──realize──▶  5 concrete environments  ──▶  P̂₁
 ├─ instance 2  (a distribution)  ──realize──▶  5 concrete environments  ──▶  P̂₂
 │  … 5 instances total …
 └─ instance 5  (a distribution)  ──realize──▶  5 concrete environments  ──▶  P̂₅

KitchenBench uses the methodology's recommended defaults: 5 instances per task (K_INSTANCES) and 5 realizations per instance (K_REALIZATIONS).

A worked example

This is one of pour_pasta's five instances (from specs.py, lightly reformatted):

TaskInstance(
    instance_id="pour_pasta/measuring-cup-to-bowl",
    goal="pour the dry pasta into the {vessel}",       # {vessel} is sampled
    setup={
        "vessel":         Categorical(("bowl", "cup", "pot")),
        "fill_g":         Uniform(80, 200),            # grams of pasta
        "pour_height_cm": Uniform(8, 15),
        "vessel_x_cm":    Normal(0.0, 3.0),            # placement jitter (cm)
        "vessel_y_cm":    Normal(0.0, 3.0),
    },
    language_vars=("vessel",),
    target_kind="pour_into",
    static={"substance": "dry_pasta"},
)

Realizing it with different seeds samples those distributions into concrete environments an operator can physically arrange (and a goal to give the VLA) (numbers rounded here for readability):

realize(seed=0)                          realize(seed=2)
  Goal: pour the dry pasta into the bowl   Goal: pour the dry pasta into the cup
  Setup:                                    Setup:
    vessel        = bowl                      vessel        = cup
    fill_g        = 156                        fill_g        = 111
    pour_height_cm = 9.9                       pour_height_cm = 10.1
    vessel_x_cm   = +0.3                        vessel_x_cm   = -7.3
    vessel_y_cm   = -1.6                        vessel_y_cm   = +5.4

Inspect and realize instances from Python:

from kitchenbench import SPEC_BY_KEY

inst = SPEC_BY_KEY["pour_pasta"].instances[0]
inst.setup_spec()
# {'fill_g': 'Uniform[80, 200]', 'pour_height_cm': 'Uniform[8, 15]',
#  'vessel': 'Categorical({bowl, cup, pot})', 'vessel_x_cm': 'N(0, 3²)', ...}

r = inst.realize(seed=0)
r.instruction     # 'pour the dry pasta into the bowl'
r.values          # {'vessel': 'bowl', 'fill_g': 156.43…, 'pour_height_cm': 9.88…, …}  (JSON-native)
r.setup_lines     # ('fill_g = 156.43…', 'pour_height_cm = 9.88…', 'vessel = bowl', …)

How it maps to a run

Each instance becomes one Inspect Robots Scene; the 5 realizations are the 5 epochs (Epochs(count=5, reducer="mean")), each seeded independently. Because the reducer is the mean, each scene's reduced task_success is the instance success probability P̂[Yᵢ = 1], exactly the methodology's estimator:

from inspect_robots import eval
(log,) = eval("kitchenbench/pour_pasta", "kitchen_scripted", "kitchen")
for s in log.samples:
    print(s.scene_id, s.reduced["task_success"])   # one P̂ per instance

On real hardware an embodiment (or operator tool) calls realize_scene(scene, seed) to get the concrete setup to arrange. Realization.setup_lines is the "arrange this" checklist, and Realization.instruction is the goal fed to the VLA.

Distribution types (in distributions.py): Uniform(a, b) continuous · Categorical((…), weights=None) over a finite set · Normal(μ, σ) Gaussian · Constant(v) fixed. Every sample is a builtin float/int/str (JSON-native), and Categorical preserves value types (an int category samples back as an int).

Validation status: read before trusting the numbers. The shipped instances are AI-authored drafts (Validation(source="opus-draft"), validated=False). The methodology's K_i = 5 is the count after human validation: 3 experts rating each instance on representativeness and quality, accepted only if both are ≥ 4. Run that commissioning pipeline before relying on the instances; we do not fabricate ratings. Also note eval()'s task-level metrics["task_success"] is the mean of P̂ over instances: a convenience aggregate, not a methodology output (the methodology sorts the per-instance P̂ into quantiles and fits the pTQ / automation-halvings curves).

Run it on real hardware (YAM arms + MolmoAct2)

KitchenBench tasks are embodiment-agnostic. To evaluate on real YAM bimanual arms with MolmoAct2, provide two Inspect Robots components (e.g. in your own adapter package such as robocurve/embodiments):

• a Policy wrapping MolmoAct2: act(observation) -> ActionChunk (the scene's instruction is fed to the VLA verbatim);
• an Embodiment for the YAM arms: reset/step/close, declaring its action space (e.g. two 7-DoF arms + grippers) and cameras. Because there is no privileged success oracle, the embodiment should turn the operator's confirmation at episode end into StepResult(terminated=True, termination_reason="success") (or set record.operator_judgement). KitchenBench's task_success scorer reads either. Declare the "self_paced" capability and pace the control loop inside step().

inspect-robots run --task kitchenbench/pour_pasta --policy molmoact2 --embodiment yam_arms

Inspect Robots checks (policy, embodiment) compatibility (action dims, semantics, camera/state keys) before any motion and writes an immutable EvalLog.

Run it in simulation

Every task instance carries a machine-readable sim annotation (see plans/0003-sim-support.md): kitchenbench.sim resolves it into a SceneBlueprint (what to spawn, where, with per-instance success parameters) and defines the benchmark's official quantitative success criteria per target kind, so a physics simulator needs no human operator. A sim embodiment (Isaac Lab, MuJoCo, …):

from kitchenbench import build_blueprint, make_success_checker

# in Embodiment.reset(scene, seed=...) — the same per-epoch seed eval() passes:
bp = build_blueprint(scene, seed)
# ...spawn bp.objects from your asset catalog (nominal dims in kitchenbench.ASSETS),
# apply bp.conditions, register the reserved names gripper_left/gripper_right...
# build the checker AFTER spawning, with the scene at rest: some criteria
# capture initial state at construction (fold's baseline footprint).
checker = make_success_checker(bp, world)   # world implements WorldState (4 queries)

# per step(): once checker(world).success, terminate with
# termination_reason="success" — the existing task_success scorer fires unchanged.

WorldState is four queries any simulator can answer (aabb, contained_fraction, contained_mass_g, opening_fraction); the criteria (nesting-aware stacking, mass-targeted pouring/scooping, transfer-detecting handoff, …) and their thresholds are versioned as SIM_CONTRACT_VERSION. Log it with your runs. Declare supported_target_kinds on your embodiment so Inspect Robots gates scene realizability before any rollout. The checkers work off poses, not sim internals, so a pose-tracked real rig can reuse them too.

Development

Dependency changes: after editing dependencies in pyproject.toml, run uv lock and commit the updated lockfile. CI installs with uv sync --locked and fails with "the lockfile needs to be updated" if you forget. Day-to-day conventions (PR-only main, the required ci-ok check, one-click releases) are documented in CLAUDE.md.

uv venv && uv pip install -e ".[dev]"     # inspect-robots resolved from PyPI (>= 0.6)
uv run pre-commit install
uv run pytest --cov                        # 100% coverage required
uv run ruff check . && uv run mypy

Every public module, class, and function needs a docstring, enforced by Ruff D1; state the contract instead of restating the symbol name.

Citation

If you use KitchenBench in your research, please cite it:

@software{kitchenbench,
  author  = {Robocurve},
  title   = {KitchenBench: A bimanual kitchen-manipulation benchmark for VLA models},
  year    = {2026},
  url     = {https://github.com/robocurve/kitchenbench},
  version = {0.3.0},
  license = {MIT}
}

License

MIT