Every op goes through ONE clear path. When the clear path does not work as expected, errors, or misbehaves, RAISE IMMEDIATELY with WHERE + WHAT failed and crash — surface the bug, fix the root cause. FORBIDDEN: silent/automated fallbacks (try/except→degraded path, except:pass, eager-replaces-fused, MSL-instead-of-tvm-ffi, gated-off-by-default, clamp-instead-of-raise, return zeros/garbage, best-effort, silent precision/shape downgrade). Fail-closed by RAISING a clear error is correct; a silent fallback producing degraded/wrong/zero output is forbidden. See CLAUDE.md. This overrides every rule below.
- Wrappers/adapters must not silently allocate or copy large tensors.
- If a design appears to require staging a large tensor, casting a large tensor, or copying a large tensor only to satisfy a wrapper boundary, treat that design as wrong and keep looking.
- Prefer passing references to existing GPU buffers, fusion, views/broadcasts, or IR-level lowering through the TileLang/TVM/tvm-ffi pipeline.
- If zero-copy/fused lowering is not currently possible, FAIL EXPLICITLY (raise with where + what). Do NOT silently fall back to another path (Rule #1).
- Dtype/shape mismatches must be solved at the right level:
- first look higher in the graph and make the producer create the tensor in the required dtype/shape from the start;
- if the current dtype/layout is the right system-level format (for example FP8 for the active config), move lower and teach the kernel to consume that format directly;
- only use casts/reshapes as explicit graph decisions, not hidden adapter staging.
- Use Codex native subagents for independent, bounded parallel work when it materially improves throughput.
- Every native subagent must use
gpt-5.6-solwithultraormaxreasoning. Useultraby default. - Do not use another model or a lower reasoning level unless the user explicitly overrides this rule.