breakdown -- convergent, action-first decomposition
The convergent complement to /fanout. /fanout opens a problem up (many valid answers); /breakdown closes one down (one tangle -> one next step). Single-shot, no sub-agents, ~1x cost. Grounded in the maintainer's session-transcript crawl: the loudest friction was "stop explaining, just do it," so this skill is ACTION-FIRST and minimal-prose by design. If your output reads like a gentle walk-through, it is wrong -- cut it.
Step 1 -- get the tangle
Accept the problem from an @-mention, a path, or pasted text. If it is genuinely vague,
ask for one or two sentences -- once. Read any referenced file to EOF before decomposing.
If the tangle is (or names) a project artifact, ALSO read that project's CHECKPOINT.md
to EOF first (receipt/preview is not a read) -- the "real goal" and the "blocking decision"
depend on live project state (deadlines, sequencing gates, what's already decided), and a
decomposition blind to it points at the wrong next action. Skip only if genuinely project-free.
Step 2 -- output exactly these five blocks, tersely, in order
No preamble. No "I have access to...". Do not restate the question back at length.
- Real goal (one sentence). What "done" actually means. If the stated goal differs from the real one, say so in one line.
- Smallest next action (one concrete, physical step doable in one sitting -- e.g. "open X and write the three field names," not "design the schema"). Then OFFER to just do it now. Do not explain at length first.
- The one blocking decision -- the single fork that unlocks the most, or "none -- just start."
- Full plan (collapsed) -- the complete checklist under a one-line summary, explicitly de-emphasized: "ignore until step 2 is done."
- First trap -- the single most likely failure mode and its earliest signal.
Rules
- One thread on the critical path. Do not list parallel workstreams.
- Plain language, no invented codes (translate any filing tags to people-words).
- Do NOT start the work until the user picks. /breakdown plans; it does not execute.
- Persist nothing by default. If worth keeping, offer to write it into the project's CHECKPOINT "Next step" line.