/ca-spike

name: ca-spike
description: Exploratory spike on a throwaway branch — answer a named question with disposable code. Never merges; exits to a findings note or $ca-feature.
argument-hint: "<question to answer> [timebox]"

$ca-spike — exploratory spike

The sanctioned lane for "I need to write code to find out." Spike code is disposable by contract: it never merges, never PRs, and never becomes the implementation. What survives a spike is the *answer*, written down — the code is burned.

Flow

1. **Name the question** — a spike without a falsifiable question is just freelancing. Restate `$ARGUMENTS` as the question the spike answers and the timebox (default: one session). STOP for the user's confirmation. 2. **Branch** — create `spike/<slug>` from the current branch. All exploratory code and experiments stay on it; only the completed findings file may later cross back to the parent. 3. **Explore** — no `tdd`, no plan, no review fleet. Two rules survive even here: no secret leaves the approved store, and no irreversible operation (prod data, destructive migration) runs from a spike. 4. **Exit — exactly one of:**

• **Answered** → write the findings to `<project-root>/.codearbiter/spikes/<slug>.md`

(the question, what was tried, the answer, what it implies), and commit only that findings file on `spike/<slug>`. Return to the parent branch and run `git restore --source spike/<slug> -- .codearbiter/spikes/<slug>.md` to transfer only the committed findings file, review it, and commit that one file through `$ca-commit`; do not merge the spike branch. Then delete the spike branch. If the answer warrants building, hand the findings to `$ca-feature` — the spike file seeds `brainstorming` ([routines/brainstorming/SKILL.md](../../routines/brainstorming/SKILL.md)); the spike code is reference material, never the implementation.

• **Timebox expired, no answer** → record that in the findings file and use the same findings-only

transfer before deleting the spike branch.

Hard gate

MUST NOT merge or PR a `spike/*` branch — its only exits are a findings file and deletion. Do not transfer spike code: the parent may receive only the committed findings file. MUST NOT copy spike code into an implementation branch wholesale; implementation re-enters through `$ca-feature` and `tdd`. Secret-handling and irreversibility rules hold even in a spike. Commits on a `spike/*` branch are exempt from `commit-gate` — the exemption is safe because no spike commit is merged and the parent may copy only the committed findings file's contents, never spike code.

When NOT to use

• You already know what to build → `$ca-feature`.
• Diagnosing a defect → `$ca-debug` (investigation with a structured exit).
• A question answerable by reading code or docs → `$ca-btw`.