What problem does it solve? Training runs that crash or get preempted lose hours of compute because checkpoints and environment state were never durably recorded. This Skill makes a Chronicle run reproducible and resumable by capturing an environment snapshot at start, streaming checkpoints to Chronicle during training, and discovering the latest checkpoint to resume from after a restart. ## Core Features & Use Cases - Environment Snapshotting: Records Python version, git SHA, installed packages, GPU/CUDA details, and custom config state as JSON at run start via run.upload_environment. - Checkpoint Upload During Training: Uploads checkpoint directories asynchronously with run.upload_directory_async, tracking state in a local SQLite UploadTracker for crash recovery. - Resume Discovery: Finds the latest ready checkpoint across all runs of a variation with run.latest_output("checkpoint") (or the MCP chronicle.list_outputs fallback) and downloads it so training continues instead of restarting. - Use Case: A long PyTorch training run crashes at step 40,000. On restart, the Skill locates the last uploaded checkpoint from the prior run, downloads it, and your load_state call resumes training exactly where it stopped. ## Quick Start Ask the agent to snapshot the environment, upload checkpoints as training progresses, and resume this Chronicle run from the latest checkpoint.