From mechanist
The single place for every data constraint an experiment must satisfy — dataset provenance (existing → adapted → constructed), clear train / validation / test splits, labels that reflect the target behavior, and the minimum data amount. Use whenever an experiment chooses, adapts, or constructs a dataset, defines splits, or sets a sample size — for phenomenon validation (M0), mechanism exploration, intervention, or tuning. Domain-general: no assumption about model family, modality, or task.
How this skill is triggered — by the user, by Claude, or both
Slash command
/mechanist:data-ruleThe summary Claude sees in its skill listing — used to decide when to auto-load this skill
All data constraints for an experiment live here. Apply them when you **design the data** (choose / adapt / construct the dataset and splits) and when you **run the experiment** — for every method and every milestone, M0 included. Use one consistent dataset; do not special-case per method or per phase.
All data constraints for an experiment live here. Apply them when you design the data (choose / adapt / construct the dataset and splits) and when you run the experiment — for every method and every milestone, M0 included. Use one consistent dataset; do not special-case per method or per phase.
Prefer an existing dataset that directly tests the target behavior. If none fits, adapt an existing one (relabel / filter / transform). Build your own only as a last resort. Record which of the three was used: existing / adapted / constructed.
Partition the data into explicit train / validation / test sets. No leakage across splits: deduplicate, and split by group / entity so near-duplicates cannot straddle the boundary. Never evaluate a probe / direction / classifier on the data it was fit on — held-out evaluation only; a score on training data is not evidence.
Labels must actually capture the target behavior the experiment is about, not a loose proxy. Ground truth comes from the dataset, never from another model's output.
Do not set up special or different data for M0 or for different mechanism methods — use one consistent dataset across them.
task.md) states a data amount, use exactly that amount.The floor is on effective sample size — the count after filtering for usable signal, capped by the number of unique source items (many derived examples from a few sources do not raise it).
npx claudepluginhub zjunlp/mechanist --plugin mechanistProcesses and analyzes data quality for ML research. Handles cleaning, missing values, feature engineering, augmentation, splitting, and dataset creation.
Designs, cleans, deduplicates, and documents datasets for ML/LLM training. Handles schema design, class imbalance, stratified splits, and dataset cards.
Guides building a representative, version-controlled evaluation dataset for LLM apps, covering data sourcing, stratification, labeling, and verification.