On this page 9 sections
Brax and MJX simulators (no helper planned)
Generated by MHS/registry/build_registry.py on 2026-10-20T00:00:00Z from 1 registry records and their task cards. A plan, not a conformance claim.
- bridge_status:
none - helper: none
- exemplar: none
Launch
Every driver package starts the same way; per-repo configuration (environment id, model path, port, baud rate, VISA resource) lives in the package's driver.py, never in launch flags:
mhs serve <driver-dir>A package is done when python3 -m mhs.driver check <driver-dir> --backend fake exits 0 (evidence contract_checked; a fake never yields an MHS-Device level).
Registry coverage
- Repos: 1
- Decisions: bridge-runtime 1
- Waves: 9: 1
- Dispatchable now: 0
- Modes: simulated 1
Applicability
Repos the catalogue files as Brax and MJX simulators. No Driver helper is planned before or after the pilot, so their cards are recon-only (wave 4) or last (wave 6: GPU, Windows or an engine licence). A simulator family needs a structural marker in the code, never only a README or name match.
Capability mapping
| native call | OpenMHS target | notes |
|---|---|---|
| construct the environment or load the model | lifecycle: construction (class attributes in driver.py) | never cap.world.reset.v1 |
| reset(seed) | cap.world.reset.v1 | output: the initial observation; a seed set with cap.world.seed.v1 applies at the next reset |
| step(action) | cap.world.step.v1 {ticks, action} | the action space becomes the input schema with per-element limits |
| get_state() / set_state() | mhs.snapshot / mhs.restore (protocol methods) | only when the engine restores the complete state; cap.world.snapshot.v1 and cap.world.restore.v1 are deprecated |
| close() | lifecycle: teardown | never cap.world.restore.v1 |
Class ids come from python3 -m mhs.driver catalog search <words>. The deprecated classes cap.device.describe.v1, cap.world.state.v1, cap.world.snapshot.v1 and cap.world.restore.v1 are replaced by the protocol methods mhs.devices.get, mhs.resource.read, mhs.snapshot and mhs.restore.
Safety
The risk floor of a device is the highest catalogue risk_class of its classes (CAP-017); a driver may declare a higher risk, never a lower one. Hardware at R1 or above needs an @estop and a non-empty safe state. The risk floor of every class still comes from the catalogue.
Fidelity
Engine-specific; nothing here claims fidelity.
Pitfalls
Batched JAX simulation conflicts with an exclusive single-device session.
First task cards
gh.google/brax: bridge-runtime, wave 9, rank 749,MHS/registry/tasks/robots/google__brax.json
Sources
- Task cards:
MHS/registry/tasks/<track>/<owner>__<repo>.json(schema/taskcard.schema.json). - Triage rules and the helper table:
MHS/registry/triage.py; curated decisions:MHS/registry/overrides/. - Driver API and gate:
MHS/sdk/docs/driver-authoring.md; exemplars:MHS/drivers/.
Packages
Top 1 of 1 by stars. Filter the full list.
| Package | Tier | Ring | Evidence | Stars |
|---|---|---|---|---|
| google/brax google/brax: physics engines for physics engines (robotics track). OpenMHS plan: SDK bridge runtime, not a per-repo driv | Tier C | 3 | agent read | 3,248 |