aidp-fixup-cell

aidp-fixup-cell — surgical re-execute of cells in a migrated notebook

The full-job migrator (job_migrate.py) runs every cell linearly with up to 10 fix attempts each. fixup_cell is the per-cell escape hatch when those 10 attempts weren't enough OR when the user discovers a latent issue downstream.

When to use

• JOB_REPORT.md shows specific cells as FAIL after aidp-migrate-job finished.
• User points at a specific cell of a previously-migrated notebook and says "this is wrong, fix it".
• User has manually edited cell K to set up a precondition, wants K+1..K+N to re-run accounting for the change.

Two invocation modes

Mode A — re-run from a history index (Opus tool)

Inside an already-running migration, Claude can call the fixup_cell tool:

fixup_cell(start_index=12, why="cell 11 redefined `<base_table>` to use a different schema; replay downstream so the new var flows through")

This is the in-process mode. It:

1. Truncates _cell_history[start_index:] (drops everything from index 12 forward).
2. Replays each old entry through _replay_cell_entry() — execute + verify + fix loop with the why injected into the Claude prompt so the model knows what changed.
3. Appends the new (post-replay) entries back to _cell_history.

The cells replayed start at the absolute history index 12 — could be in the SAME notebook or a downstream one if the cells were inlined via %run.

Mode B — standalone replay against a saved notebook

When the migration is done and the user wants to "fix this one cell":

python3 ${CLAUDE_PLUGIN_ROOT}/engine/scripts/job_migrate.py \
  --manifest reports/<MyJob>_manifest.json \
  --cluster <CLUSTER_ID> \
  --only-tasks <task_key> \
  --no-skip-migrated

This re-runs that single task end-to-end (deps already cached → fast). Combine with --start-task <substring> to run only that one task.

If the user wants finer-grained control (specific cell, not full task), they need to open the saved .ipynb and edit manually. The migrator doesn't expose a "replay cell K only" CLI outside of the in-process fixup_cell tool.