neuron-tai/.scratch/distributed-gguf-runtime/issues/025-define-exact-artifact-and-runtime-recipe-identity.md

DGR-025: Define exact artifact and runtime recipe identity

• Status / triage: specification only; ready-for-agent; passes: false
• Execution mode: AFK
• Milestone: M1
• Dependencies: DGR-018, DGR-021
• Blocks (derived): DGR-026, DGR-031, DGR-041, DGR-044
• Labels: area:identity, area:admission, type:domain, priority:p0, ready-for-agent
• Evidence class: model-free
• Hardware: none
• Model: generic
• Upstream: no

Objective / description

Fresh Ralph session: read .scratch/distributed-gguf-runtime/RALPH-CONTEXT.md, source issue .scratch/distributed-gguf-runtime/issues/025-define-exact-artifact-and-runtime-recipe-identity.md, and evidence READMEs for dependencies (DGR-018, DGR-021) before changing code. Inspect live source/tests rather than trusting legacy pass states. Objective: Ensure the tracker and worker only combine numerically and operationally compatible shards.

Acceptance criteria

• Fingerprint source artifact SHA, tokenizer revision, architecture adapter/version, boundary schema, runtime pin/patch stack, backend, quant, activation/compute dtype, and KV/state layout.
• Bind each shard to an exact half-open range without hardcoding a topology or quant.
• Fail closed on any artifact, adapter, boundary, cache, backend, or runtime mismatch.
• Unsupported recipes remain registered-but-dark until real-hardware evidence certifies them.
• Applicable shared quality gates in prd.json pass, and the evidence handoff records exact commands/results, changed files, limitations, and dependency handoff.

Shared quality gates

• Targeted deterministic tests pass; Python changes also pass python -m compileall packages tests.
• git diff --check passes.
• Default tests are model-download-free, API-credit-free, and GPU-free.
• Evidence README records exact changed files, commands/results, limitations, and dependency handoff; no fabricated evidence or inherited completion credit.
• Native changes pass focused out-of-tree CMake build and CTest; patch changes verify clean apply/check/reverse against the exact llama.cpp pin.
• Runs are opt-in and record exact artifact/split hashes, runtime/upstream pin, backend/driver, hardware, network, commands, and raw metrics. Model artifacts use configured mounted-drive storage and never /home.
• Preserve existing Transformers behavior and backend-agnostic Tracker routing/load balancing/billing/relay semantics unless an explicit versioned contract says otherwise. One scoped story commit is expected during execution, but this specification-materialization change is not committed.

Evidence handoff

Write and verify .scratch/distributed-gguf-runtime/evidence/DGR-025/README.md. Until every criterion and applicable gate has real evidence, this story remains passes: false. Legacy evidence is provenance only, not completion credit.