Use when porting R logic into the Python SportsDataverse package (sdv-py) — e.g. translating an nflfastR / cfbfastR / cfbscrapR / baseballr / hoopR R function, reconciling a fix from the pandas `0.36-live` branch into polars `main`, or re-implementing a modeling recipe (EP/WP/QBR/CPOE) from R. Enforces a parity-test-first workflow (golden fixture from the R output → failing parity test → port → green) and the polars-1x + ID-dtype + no-lookaround conventions. Also covers R numeric fidelity when outputs must match R bit-for-bit (R>=4.0 fround, 80-bit long-double sum, non-na.rm null-poisoning, dplyr group order), stale-fork sibling packages (wbigballR-style), and oracle integrity (a browser/rvest-captured oracle can be corrupt — fix the bug, don't match it). Invoke for "port this R function to polars", "port from nflfastR/bigballR", "reconcile 0.36-live into main", "translate this dplyr/np.select to polars", "re-implement the R model recipe in Python", or when a parity test fails on a handful of rounding-boundar
Use when shipping a change in sportsdataverse-py (sdv-py) — opening, pushing, or merging a PR. Runs the steps in the correct order (regenerate codegen docs, update changelog/docs/tutorials, lint, full pytest, commit + verify it landed, push, triage bot reviews CodeRabbit/Sourcery/Copilot immediately — in parallel with CI, not after it — wait for CI green, confirm merge, write a session note) and never cleans up a branch before the merge is confirmed. Invoke for "ship this", "open/merge the PR", "land this change", or any end-of-change release flow.
Use when executing a model-spine implementation plan (the ClaudeCowork specs/plans backlog — prediction stacks, ratings engines, projection/impact models) or building any oracle-gated analytics module in an SDV repo. Covers the full loop — isolated worktree + baseline, Phase-0 oracle harness (metrics/constants/leakage split/fixtures), per-task TDD with verified commits, oracle gates with the never-lower rule, league-shim parity, mypy/codegen close-out, reviewer pass, and the session restart prompt. Invoke for "implement T<x>", "start the <sport> model spine", "continue the prediction stack", or any multi-phase model build.
Use when capturing an external oracle/validation corpus into committed test fixtures — Torvik/KenPom ratings, ESPN BPI/predictor/odds, market closing lines, MoneyPuck, published RAPM/EPM, or any third-party reference a model gate will assert against. Covers column contracts, Utf8-id discipline, the team/player name-crosswalk recipe (contracting normalizer + candidate keys + alias table + match-rate reporting), rate-limit-aware sampling, and the mandatory provenance README. Invoke for "capture the oracle corpus", "commit the <source> fixtures", or any Task-0-style fixture capture in a model plan.
Use when porting Python logic from the SportsDataverse Python package (sdv-py) into a SportsDataverse R package — cfbfastR, hoopR, wehoop, baseballr, fastRhockey, softballR, etc. Enforces a parity-test-first workflow (golden fixture from the Python output → failing testthat test → port → green) plus the tidyverse/data.table idiom map and R package conventions (roxygen2 docs, snake_case, tibble returns, pkgdown reference coverage). Invoke for "port this to cfbfastR", "translate this polars logic to dplyr", "re-implement the sdv-py parser in R", or "bring this Python fix back to the R package".
Add a CBS Sports (NAPI) league/resource — capture + catalog in sdv-internal-refs/cbs.
Register a new ESPN league family in sdv-py — leagues.yaml row, pre-create package dir + __init__, regenerate, gated live test, verify the drift gate.
Add a Fox Sports (Bifrost) league/sport — capture + catalog in sdv-internal-refs/fox.