spike

name	spike
description	Read-only multi-axis direction investigation that unblocks /roadmap propose or /design: N rounds x M axis picks, optional postmortem + scope deltas. No state mutations.
argument-hint	<spike-slug> [--final] [--from-briefs <path1,path2,...>] [--postmortem <phase-id>]
user-invocable	true
disable-model-invocation	false

/spike

Purpose

A spike is a time-boxed read-only investigation that produces direction — picks across many design axes — to unblock the next planning skill. Direction-only means no wave plan, no success criteria, and no EU estimates fall out of a spike; those belong to /design and /roadmap propose. Spike writes only under .ea/local/.

Three failure modes it prevents:

1. Single-verdict context loss. /research answers one question; a rebuild or phase-opening decision has many entangled axes. Spike runs them as multi-round AUQ batches in one session with a rolling matrix.
2. Silent scope creep. Mid-session picks can quietly expand or reduce surface vs prior briefs. Spike surfaces scope deltas as a mandatory section when prior briefs exist.
3. Postmortem-without-next-plan. Spike couples a postmortem (gap matrix + root causes + salvage matrix) to direction picks in the same brief so the rebuild plan inherits the lessons.

When to invoke

Reach for /spike when multiple decisions block /roadmap propose and must be picked together to stay coherent, when a prior attempt shipped but missed its briefs and the next phase is a rebuild, or when direction picks span scope-expansions and -reductions that need explicit acknowledgement. Pick a neighbour instead when one unknown blocks progress and a single verdict lands it (/research), or when direction is locked and an interactive surface needs a full statechart

• matrix + journey design (/design).

Canonical algorithm

1. Resolve the slug from the argument or AUQ. Filename stem: <YYYY-MM-DD>-<slug>.md.
2. Frame the multi-axis unknown in one paragraph; list the prior briefs feeding the spike (--from-briefs). On --postmortem <phase-id>, declare the phase under postmortem.
3. Survey: read the cited prior briefs, read source on the verdict ladder (verify-before-claim), run git log for shipped-vs-spec drift. Optionally dispatch worktree subagents for independent investigative arms; the parent compiles the chunks.
4. Multi-round AUQ picks. Each round = 3-6 axes batched into one AskUserQuestion call. Decisions accumulate into the rolling matrix; round-close is gated on all axes in the batch answered.
5. Scope-delta surfacing. When picks diverge from prior briefs, record explicit expansion and reduction tables, each row citing the original brief line and the new pick.
6. Critical-contracts capture. When picks ripple into process changes (commit-prefix lint, success-criteria shape, schema migration, audit kind), surface them with enforcement + effect named.
7. Open follow-ups. Enumerate explicitly — "none" is rare. Label each with a next-action (next-spike, next-research, hypothesis-open, blocked-on-EU, blocked-on-demo).
8. Hand-off declaration. The Summary closes with a literal next: line naming the unblocked skill and its args.
9. Self-lint, then write (on --final) .ea/local/research/<YYYY-MM-DD>-<slug>.md with the sentinel <!-- eawf-template: spike-brief --> on line 1. Return the output envelope.

PoC allowance + execution-spike isolation

A spike MAY produce throwaway runnable artifacts to ground direction picks — smoke demos, probe scripts, config experiments — under .ea/local/ only (.ea/local/smoke/<slug>/, .ea/local/poc/<slug>/, or .ea/local/research/notes/<slug>/), gitignored, with a manifest table + a "How to run the PoCs" section when >=1 is built.

A direction spike is read-only. An execution spike writes code to ground a verdict against a running artifact, so it needs isolation the read-only flow does not. Zero-internal-dep throwaway scripts stay in the local gitignored PoC scope. Code that imports eawf.* runs in a dedicated worktree branch off the current feature-branch HEAD (feature/<symbol>-vX.Y-spike-<slug>); on a green verdict the commits are cherry-picked into the feature branch (never merged), and on a rejected verdict the worktree is torn down. Do NOT commit spike code straight onto the shared feature branch — a pre-verdict commit interleaves with concurrent sessions and bakes unratified experiment into history.

Brief chassis

Required sections (the writer rejects on missing): frontmatter (scope URN, status=local-draft, created date, agent); the sentinel on line 1; Summary (verdict rollup + direction bullets + the next: line); a decision matrix (>=1 round table when picks were made, else a Findings section); Open follow-ups (labelled); References (dense [N] rows, repo-relative + external URLs + Eä URNs); Provenance (store_record=none (local-only spike), starting commit SHA, session slug); and Scrub (repo-relative paths only, no PII, placeholder names when project codes appear). Conditionally required: the PoC manifest + run guide when >=1 PoC was built, the postmortem arc when --postmortem is passed, and the scope-delta tables when --from-briefs cites prior briefs.

Pre-flight checklist

• No state mutations; state.json untouched. PoCs under .ea/local/{smoke,poc,research/notes}/ only (gitignored).
• If an execution spike that landed runnable code — code is isolated (worktree branch for internal deps, local PoC scope for zero deps) and ships a .ea/local/ user test guide.
• Multi-round picks via AskUserQuestion, never free-text; recommended option first, labelled.
• Every direction pick carries a one-line rationale ([N] cite or "because X").
• Scope deltas surfaced when --from-briefs cited; critical contracts surfaced when picks ripple into process change.
• Open follow-ups enumerated with next-action labels; next: line present in the Summary.
• References dense [N], repo-relative only; Provenance records the starting commit SHA + session slug; Scrub confirms no PII.
• Brief filename <YYYY-MM-DD>-<slug>.md under .ea/local/research/; sentinel <!-- eawf-template: spike-brief --> on line 1.

Decision surfaces

Round axis picks, scope-delta acknowledgement, and the hand-off declaration are all surfaced through AskUserQuestion batches — the hand-off AUQ options name the unblocked skill (/roadmap propose, another /spike, /research --final, or /design).

Output contract

Eä-rendered envelope (OutputEnvelope) with header.skill = "/spike". Body carries the Summary + next: line, the round tables (decision matrix), the postmortem arc when --postmortem, the scope deltas when --from-briefs cited, the critical contracts when applicable, the labelled open follow-ups, and the References + Provenance + Scrub chassis tail. The footer records the persisted brief path + sentinel when --final was passed.