Design

The layers, contracts, catalogs, data flow, and design choices that make WorldFoundry extensible and auditable.

On this page

WorldFoundry follows one primary design rule: separate model execution from benchmark evaluation, and connect them with explicit artifacts and evidence. That lets very different systems share one research workflow without putting model-loading code inside metrics, or benchmark assumptions inside model pipelines.

The contracts below are accountable to the operational definition of a world model: persistent state, intervention-conditioned dynamics, and feedback-driven updating. WorldFoundry standardizes discovery, execution, artifacts, and evidence — not a single model interface or undifferentiated ranking.

The artifact boundary

The primary rule in one picture: model execution and benchmark evaluation meet only through normalized artifacts. A model produces GenerationResult rows; a benchmark consumes them. Neither side reaches through the boundary for the other's internals.

Boundary
The artifact boundary
Model execution
InputGenerationRequest
RuntimePipeline + Operator
InferenceNative inference

Model side never imports a benchmark evaluator

Artifact boundary
GenerationResultartifacts.jsonl
Benchmark / reporting
EvaluationBenchmark runner
Metricsper_sample + summary
Reportscorecard.json

Benchmark side never loads a model checkpoint

Nothing else crosses: no checkpoint paths into metrics, no evaluator imports into pipelines.

The four-layer overview below maps where these two sides live; the boundary diagram above is the zoom-in on their interface.

Architecture at a glance

The four-layer diagram below is a coarse overview of how the system is grouped. The authoritative ownership model is the seven responsibilities in Architecture — each with explicit “owns X / must not own Y” rules. When a change touches ownership, resolve it against that list; treat this diagram as a map of the map, not the contract.

01
SurfacesEntry points for people and agents
TUICLIStudioPython APIMCP
02
Control planeRunnable entries, dependencies, and dispatch
Model catalogBenchmark catalogReadinessRun plans
03
ExecutionWhere model inference and benchmark scoring happen
PipelineOperatorModel runnerBenchmark runner
04
Contracts & evidenceWhat crosses subsystem boundaries and survives a run
RequestResultArtifact manifestScorecard
Each layer owns one kind of change. Serializable contracts keep model-specific code, benchmark-specific code, and user interfaces from leaking into one another.

The four layers have different responsibilities and different rates of change.

The surface layer is how people and agents operate the system. Six surfaces share the same catalogs and run contracts; they differ by who drives the work.

  • TUI — guided entry. Reads the same manifests as the CLI, helps select IDs, and can print the final command before launching expensive work.
  • CLI — automation surface. Covers discovery, asset checks, task and dataset materialization, run planning, inference and evaluation, reporting, comparison, validation, and machine-readable JSON output.
  • Studio — browser workspace. Provides model-aware job forms, inference history, galleries, and visualizers for media, geometry, timelines, simulators, and interactive model output. Jobs write durable outputs that can be evaluated later; results are not trapped in the UI.
  • Python API — research contracts. Exposes public request, result, run, metric, and reporting types for in-process research code.
  • MCP server — agent tools. Exposes bounded discovery and evaluation tools for agent-driven workflows.
  • Shell helpers — escape hatch. Stay available for model families or environments whose upstream details do not fit cleanly into a generic command.

These surfaces may collect different inputs, but they should not contain private model implementations or scoring logic.

The control plane answers what exists, what can run, what it needs, and how it should be dispatched. Model and benchmark catalogs, aliases, asset declarations, runtime profiles, readiness fields, and run plans live here. This layer describes and routes work; it does not execute GPU kernels or compute benchmark scores.

The execution layer contains model pipelines and operators on one side, and benchmark runners and metrics on the other. Model code owns checkpoint loading and generation. Benchmark code owns protocol-specific scoring and result normalization. Neither side should reach through the artifact boundary and take over the other side's responsibility.

The contract and evidence layer is what survives the process. Requests, results, artifact references, manifests, reports, and scorecards are serializable. They keep a run understandable after the Python process has exited, and let generation and scoring happen in different environments, on different machines, or at different times.

Catalogs: knowing what exists

The Model Zoo assigns stable IDs and aliases to world-model systems. A model manifest can record tasks, upstream sources, checkpoint references, variants, runtime bindings, install profiles, hardware expectations, validation notes, and known blockers. See the model catalog for current coverage; an entry does not imply a runnable runtime.

Those entries are organized around five operational families. The video catalog covers text-, image-, and video-conditioned generation, editing, animation, and audio-video systems. The world-model catalog focuses on interactive worlds, navigation, action or camera conditioning, and simulators. The 3D/4D catalog includes reconstruction, depth, point clouds, scene representations, and dynamic geometry. The VLA/VA/WAM catalog covers embodied policies and world-action systems. A separate hosted-API catalog covers provider-backed systems whose weights are never loaded locally.

The Benchmark Zoo plays the same role for evaluation protocols. Its benchmark hub covers generated-video quality, physical and dynamic consistency, camera and 3D/4D behavior, world-model capability, safety, memory, and embodied control. A benchmark manifest can declare datasets, generated-output layouts, metric assets, official commands, normalizers, runtime profiles, eligibility conditions, and blockers.

Query the catalogs before downloading anything:

worldfoundry-eval zoo models --json
worldfoundry-eval zoo benchmarks --json
worldfoundry-eval zoo model-show --model-id <model-id> --include-manifest --json
worldfoundry-eval zoo benchmark-show --benchmark-id <benchmark-id> --json

The detailed model index lives in Models. Benchmark requirements and current execution paths live in the Benchmark Hub.

Runtimes: turning declarations into work

Model execution runs through in-tree pipelines and operators, local checkpoint loaders, hosted API adapters, subprocess launchers, and dedicated-environment dispatch. A pipeline stays close to the model's native implementation; an operator adapts that implementation to WorldFoundry requests and artifacts.

So WorldFoundry can support models with very different inputs and outputs without flattening them into an artificial lowest-common-denominator interface. A text-to-video model can expose prompt and sampling controls, a camera-conditioned model can accept trajectories, a 3D system can emit geometry, and a robot policy can produce actions or traces. Their native differences stay visible, while their execution status and outputs enter the same reporting system.

Some runtimes work inside the unified environment. Others require a dedicated conda profile, an official upstream environment, a simulator container, or an API credential. The environment reference explains how these profiles are selected; the local assets guide explains where checkpoints, datasets, and metric weights live.

End-to-end data flow

  1. Discover

    Choose a model and benchmark

    Catalog manifests expose stable IDs, capabilities, readiness, assets, and blockers.

  2. Prepare

    Stage runtime and assets

    Resolve the conda profile, checkpoints, datasets, metric weights, and credentials.

  3. Run

    Generate through one contract

    TUI, CLI, scripts, and Studio dispatch to a pipeline and operator.

  4. Inspect

    Review normalized artifacts

    Videos, geometry, actions, traces, and metadata remain visible and reusable.

  5. Evaluate

    Produce reviewable evidence

    Metrics and official runners write reports, blockers, and a normalized scorecard.

Artifacts are the handoff: model runtimes do not own benchmark logic, and benchmark runners do not load model checkpoints.

A run begins with declarative identities. A model manifest and benchmark manifest record source provenance, intended capabilities, requirements, runtime bindings, and known blockers. User input, task metadata, or a dataset sample is then normalized into a GenerationRequest.

A WorldModelRunner resolves the requested model and dispatches to the correct pipeline/operator or external runtime. The runner returns a GenerationResult that describes status, timing, errors, metadata, and durable outputs. Those outputs may be videos, images, frames, geometry, point clouds, actions, trajectories, traces, or structured data.

Evaluation consumes the result rather than the checkpoint. Reusable metrics or benchmark-specific runners read the generated artifacts, produce per-sample metric rows, and aggregate them according to the selected protocol. Reporting then consolidates run identity, provenance, coverage, blockers, and scores into the run record.

The file boundary is intentional. A costly generation job can finish once, be visually inspected, and later be evaluated by a new metric without loading the model again. A benchmark can also run in a dedicated environment without forcing its dependencies into every model runtime.

Example: one Matrix-Game 2 output crossing the boundary

A Matrix-Game 2 universal run uses a user-provided initial image together with an action-conditioned configuration. Pass the image path explicitly when configuring the run. The operator translates those inputs into the native model call, the pipeline owns checkpoint execution, and the output side writes video and metadata.

Call graph
Matrix-Game 2 across the boundary
InputImage + action sequence + seed/fpsuniversal/0000.png
shape native call
OperatorMatrix-Game 2 operator
run checkpoint
PipelinePipeline / checkpoint
write video + metadata
Outputgenerated_video + metadata
wrap as artifact ref
ContractArtifactRef in GenerationResult
cross the boundary
ConsumeVisual review or a compatible metric
Evaluation only needs artifact kind, URI, and sample identity — not how weights were loaded.

Evaluation only needs the artifact kind, URI, and sample identity; it does not need to know how Matrix-Game 2 loads its weights. Conversely, the pipeline never imports a benchmark evaluator. If generation succeeds but the benchmark's required prompt set is incomplete, the GenerationResult can still be valid while leaderboard eligibility in the scorecard stays false.

Evaluation: from artifact to evidence

The evaluation core can score existing result ledgers, run registered models over materialized requests, execute a model × benchmark cell, resume or cache selected work, compare runs, and build suite-level reports. Reusable metrics are kept separate from full benchmark protocols, so a scorer can be applied to compatible artifacts without claiming that the entire official benchmark was reproduced.

Benchmark integrations mature in stages. Some provide metadata and an asset plan. Some can normalize an existing official-shaped result. Some expose in-tree metric execution or an official runner facade. A smaller subset has bounded runtime evidence, and full leaderboard eligibility requires the protocol-specific data, coverage, credentials, and validation gates to be satisfied together.

That staged model is deliberate. It lets useful catalog and normalization work land without overstating what is runnable or official.

Reporting: what remains after a run

WorldFoundry treats the run directory as a research record, not a disposable cache. A typical run preserves a manifest describing identity and configuration, a request ledger showing the samples or conditions that were asked for, and a result ledger recording per-sample status, timing, errors, and artifact references.

The generated artifacts themselves may include videos, frames, images, geometry, point clouds, trajectories, actions, traces, or structured rows. Metric summaries retain machine-readable aggregates, while report.md and summary.json provide human and compact programmatic views. scorecard.json adds coverage, provenance, blockers, validation state, and eligibility to the scores.

Exact files depend on the run mode and integration. The contract is that unavailable work stays unavailable: a scorecard must not turn a missing dataset, skipped sample, or unverified official path into apparent success.

What is intentionally not bundled

WorldFoundry does not redistribute model checkpoints, gated weights, full benchmark datasets, simulator assets, API keys, private endpoints, or normal user outputs. It also does not vendor every upstream training stack, or guarantee that every model × benchmark pair is meaningful.

Those boundaries keep the repository reviewable and respect upstream licenses. The checked-in code describes how external assets connect to a run and reports when they are missing; it never silently downloads or substitutes protected resources. Licensing and provenance for in-tree upstream code are recorded in the repository files linked from Third-party notices.

Where the layers live

Model identities and requirements live under worldfoundry/data/models/catalog/. Model execution is implemented across worldfoundry/pipelines/, worldfoundry/operators/, and worldfoundry/synthesis/. Benchmark metadata, assets, tasks, and runtime profiles live under worldfoundry/data/benchmarks/, while public evaluation contracts, runners, metrics, reports, and scorecards live under worldfoundry/evaluation/.

The browser workspace and visualizers live under worldfoundry/studio/. Discovery, planning, execution, validation, and reporting commands live under worldfoundry/cli/. Supported operational helpers are grouped under scripts/setup/, scripts/inference/, and scripts/workspace/.

For source-level call chains and extension boundaries, continue to the maintainer architecture guide. It also has dedicated subsystem pages: Codebase map, Surfaces and orchestration, Runtime assembly, and Core infrastructure.

Principles used when making changes

Evidence comes before claims. A manifest records intent; runtime and scorecard evidence justify readiness.

Artifacts are first-class. Results remain inspectable and reusable after the process exits.

Explicit blockers beat silent fallback. Missing assets, credentials, coverage, or official parity must remain visible.

One core supports multiple surfaces. TUI, CLI, Studio, Python, scripts, and MCP reuse the same catalogs and execution paths.

Model differences are preserved. WorldFoundry normalizes subsystem boundaries and evidence, not every native parameter or representation.

Official validation is not official reproduction. Importing official-shaped results proves the normalization path; it does not prove full benchmark parity.

Where to go next

To browse available systems, continue to Models and the Benchmark Hub. To generate an artifact, follow Run inference. To score existing or newly generated output, read the Evaluation overview. To add coverage, use Add a model or Add a benchmark.