foolish-debugging
MUST USE for debugging Foolish FVM/FIR behavior — wrong brane evaluation, unexpected NK/ECONSTANIC, search resolution failures, NYES state machine bugs, name-lookup errors. The Foolish VM has no interactive debugger; debugging is unit-test-driven: write a temporary test that reproduces the issue, step the FVM to the offending line, inspect FIR NYES state and query the FVM via ib_search/ab_search, then promote the test to a regression test or delete it. This skill gives the exact Rust API and copy-pasteable templates. Triggers: 'debug Foolish', 'FVM bug', 'NYES wrong', 'brane not resolving', 'search returns NK', 'ib_search', 'ab_search', 'why is my brane NK', 'FIR state', 'step the FVM', 'foolish unit test debug', 'temporary_reproduce_to_debug'.
foop-use-maintain
MUST USE when FINDING, EXECUTING, UPDATING, BACKBURNERING, or CANCELLING existing FOOPs (Foolish Optimization Process). Covers: listing/finding FOOPs in chronological order (little-endian ls|rev|sort -V|rev, foop_check.py list/get_last/check), the two-file system (must read both spec and plan before executing), status lifecycle (Draft→Brewing→Final→Implementing→complete), plan execution flow (begin→worktree→all-work-in-worktree→commit-regularly→merge), checkbox lifecycle (completing with timestamp, backburnering with [x] backburnered, cancelling with [x] Canceled + [-] per-item), worktree execution (create from jia, work only in worktree, merge to jia, cleanup), sub-task execution patterns (parent not checked until children done, the merge STOP pattern, conflict repair because Foolish uses merge not rebase), comprehensive test verification, human communication protocol (PTAL reminder with FOOP number and worktree path), and safety invariants. Gives exact copy-pasteable commands with <NUMBER> and <SHORT_DESCRIPTION> placeholders. Triggers: 'find foop', 'list foop', 'execute foop', 'foop status', 'foop execution', 'check foop checkbox', 'backburner foop', 'cancel foop', 'deprecate foop', 'foop merge', 'foop cleanup', 'foop worktree', 'foop begun', 'foop progress', 'resume foop', 'foop PTAL'.
foop-write-plan
MUST USE when CREATING or PLANNING a FOOP (Foolish Optimization Process) — writing the specification file (FOOP-#.md) and the plan file (FOOP-#.plan.md). Covers: what a FOOP is, the two-file system (spec + plan), little-endian numbering (FOOP-1→FOOP-9→FOOP-01→FOOP-11→FOOP-21...), the foop_check.py helper script (check/get_last/gen_next/list), naming convention (dash in filenames, space in prose), the spec template (frontmatter fields foop/title/status/phase/begun, body sections Abstract/Motivation/Specification/FIR Impact/UBC Step Impact/Test Plan/Rejected Alternatives/Open Questions/References), the D-prefix sort-key rule, plan construction rules (ordered/concrete/trackable, worktree lifecycle checkboxes, sub-tasks, variable expansion), checkbox format (timestamp on next indented line), sub-task splitting, worktree branch tracking (naming, creation, lifecycle checkboxes), comprehensive snapshot tests (foop_<NUMBER>_comprehensive.foo), and the minimal plan skeleton. Gives exact copy-pasteable commands with <NUMBER> and <SHORT_DESCRIPTION> placeholders. Triggers: 'create foop', 'new foop', 'write foop', 'foop spec', 'foop plan', 'foop template', 'foop numbering', 'foop frontmatter', 'foop_check gen_next', 'plan a foop', 'foop worktree setup', 'foop comprehensive test'.