for-each

name	for-each
description	Process a list of items by dispatching ONE sub-agent per item, strictly sequentially (await each before the next). Same per-item sub-task and final summary contract as map-reduce — only the dispatch order differs. Only invoke when the user explicitly asks for the for-each skill or pattern by name. Do not auto-select for general tasks.
metadata	{"author":"Yiheng Tao","version":"0.0.1"}

For-Each (Sequential)

Use when items must be processed in order, or earlier results inform later ones, or you want simple linear debuggability. For fully independent items where throughput matters, use map-reduce instead. The per-item sub-task and final summary contracts below are identical between the two skills.

Workflow

1. Identify the item list. If the user did not provide it, ask once via ask_user. Confirm before proceeding if there are more than 5 items.
2. For each item, in input order, dispatch a sub-agent for the per-item sub-task. Await completion before dispatching the next. Never run two mappers concurrently.
3. After every item has settled (success or recorded error), produce the final summary.

Per-item sub-task (identical to map-reduce)

Dispatch one sub-agent per item with:

• A stable item id plus enough metadata to act on it (path, URL, identifier).
• The user-provided task description, scoped strictly to that item.
• An expected result shape: short structured output with key findings, evidence pointers, and a confidence note.
• Instruction: do not summarize across items, do not process items outside the assigned one, and on unrecoverable failure return { id, error } instead of raising.

Use claude-sonnet-4.6 or gpt-5.4 for mappers. Prefer the explore agent for read-only work and general-purpose for mutations.

Final summary (identical to map-reduce)

Dispatch a single summary sub-agent (or produce inline) that reads every per-item result and writes a markdown report containing:

• A header line "N of M items succeeded".
• A table or sectioned list keyed by item id with key findings.
• A dedicated "Errors" section listing every { id, error } result.
• Actionable next steps if any.

Use claude-opus-4.6 for the summary. Present the final report to the user.