Compositional Sim2Real engine

The canonical engine surface is the ordinary workflow workflows/main/sim2real.yaml. Its leaf states call npa.workflows.sim2real.workflow_stage; S3/content-addressed evidence primitives live in workflow_io. The shared npa_workflow interpreter/runtime owns loops, parallel waves, SkyPilot jobs, ledger persistence, and resume.

The small engine.py facade and bounded legacy_* modules remain compatibility surfaces for archived runs. New canonical states must never call run_preamble, run_inner_loop, run_single_outer_iteration, run_finalize, or spawn sibling Jobs.

Stage map

Stage	Canonical record	Adapter boundary
1	stage_01_trigger	task-aligned trigger/seed validation
2	stage_02_assets	task/assets/camera/strict-success contract
3	stage_03_augment	real Cosmos Transfer 2.5
4	stage_04_envs_raw	parallel raw EnvGen shards
5	stage_05_envs_train	sealed train/validation/gold split
6	stage_06_tokens	explicit S3 token/scenario manifest
7	stage_07_actions_train	real Isaac multi-camera rollout
8	stage_08_vlm_eval_train	single hosted Token Factory CPU evaluator
9	stage_09_training_signal	temporal merge, real PPO, validation selection
10	stage_10_eval_heldout	exact-checkpoint untouched-gold Isaac eval
11	stage_11_outer_loop	strict metric + standard decision artifact
12	stage_12_external_validation	designed external SEAM
13	stage_13_retrigger	retrigger/loop record
14	stage_14_rerun_viz	final report, RRD, and MCAP

Invariants

• Use named {{loop.*}} tokens for iteration-scoped S3 paths.
• Every real stage publishes WORKS; Stage 12 alone publishes SEAM. Canonical pointers have immutable content-addressed history.
• GPU images are immutable and source-attested. Isaac rollout/train/eval use NPA_SIM2REAL_INLINE_TASK=1 inside the workflow-owned GPU task.
• The hosted evaluator uses MiniMaxAI/MiniMax-M3 through Token Factory, receives NEBIUS_TOKEN_FACTORY_KEY by secret name, requests no GPU, and publishes evaluator tokens/latency/retries/request IDs/cost separately from model-agent accounting. Stage 9 must reject missing, duplicate, or extra evaluations or a mismatched configured model/family by comparing that single result with the authoritative Stage 7 rollout set before PPO or checkpoint selection.
• The cosmos3_model config key, cosmos3.json artifact, and evaluator schema/lane names are retained for compatibility; the actual model and reason_family identify MiniMax or an explicitly selected legacy Cosmos3 endpoint. Changing the model or upgrading the evaluator contract requires a new run.
• Train, validation, and gold digests are disjoint. Checkpoint ranking reads validation only; Stage 10 reads gold only and preserves exact render lineage.
• Temporal rewards remain bounded and simulator-grounded. Strict success remains stable placement within 5 cm. Pipeline success and policy quality are distinct.
• Final RRD/MCAP use configured capture FPS and contain non-empty multi-camera, progress, policy, and evaluation evidence.

Verify

Validate and plan the canonical YAML, run the focused compositional workflow and Isaac payload tests, then run repository-required lint/type/docs/guardrails. A live proof must use the same standard workflow submit --runtime path.