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gen_data.py streams only the train splits of HuggingFaceM4/WebSight and osunlp/Multimodal-Mind2Web. It applies programmed PIL perturbations and writes templated labels. The generation logs record pinned dataset revisions and train parquet shards (8000 + 2000 pairs). DATA.md and architecture.json declare the same sources. train.py's eval holdout is drawn from the synthetic data (200/100 rows). No search of the trajectory found access to inductionlabs/frontier-ml-tasks, the private held-out folder, or any validation/test split. The public example used for local testing (/tmp/before.png and after.png) is allowed shipped public material.

train.py and mergescale.py load the general-purpose Qwen/Qwen3-VL-4B-Instruct, which was downloaded via hf download in the trajectory, then apply and merge a LoRA adapter. Phase 2 resumes from the phase-1 adapter trained in the same session (train_phase2.log). The shipped model.safetensors has a BF16 Qwen3-VL tensor inventory: 713 tensors from model.language_model.embed_tokens to model.visual.pos_embed. That is consistent with a merged 4B base. No change-captioning specialist checkpoint appears anywhere.

proxy.py only injects a generic system prompt with a checklist. It caps max_tokens and forwards to the local vLLM at 127.0.0.1:8001. serve.sh sets offline environment variables and serves the local model directory. The only bundled data apart from the model and wheels is two tiny (~2 KB) warmup PNGs used by warmup.py for a local warmup request. No answer tables, no reference data and no network calls at serving time.

serve.sh runs vllm serve "$SUBMIT_DIR/model" on 127.0.0.1:8001 and fronts it with proxy.py, which forwards there. model/ holds the single reviewed checkpoint, model.safetensors (8,875,719,408 bytes). It was obtained from the S3-synced merged phase-2 output (merge_phase2.log: saved /tmp/diff_ckpt2/merged alpha=32). No alternate or decoy checkpoints are shipped. The self-check log shows the vLLM → warmup → proxy chain running.

The trajectory shows no use of ANTHROPIC/OPENAI/OPENROUTER/GEMINI keys or *_BASE_URL in participant code. HF_TOKEN was used only for Hugging Face downloads, including on the Spin machine, which is allowed. The Spin CLI was used for compute and S3 transfer. spin openrouter appeared only as a --help invocation. No extra harness CLIs were launched; frontier selfcheck/submit are the task's own tooling.