Agent workflow: jackin❯-native spec-driven workflow

Status: Open — iterating. The roadmap item .mdx is the living change-spec (## Problem/## Design/## Tasks while open, retiring into canonical docs on ship); the in-repo jackin-dev helper backs the human PR workflow. No external spec tool was adopted.

Shipped facts

The workflow convention itself has landed and is in active use: roadmap items carry ## Problem / ## Why It Matters / ## Design / ## Tasks sections while a change is open, and retire into canonical docs once shipped — there is no parallel openspec/ directory or separate internal/specs/ tree in the repo. The jackin-dev helper (crates/jackin-dev/src/main.rs) lives in this workspace and drives the PR sync/status/env/path/explain subcommands that support this workflow day to day.

This is the initial iteration, not a finished design — the shape above is expected to keep changing as it gets used.

Remaining work

1. Decide whether jackin❯ eventually grows its own spec-driven tool (cc-sdd/OpenSpec-like), or keeps the current skills + roadmap-item model.
2. Build the deferred plan skill that mechanically breaks a roadmap item's ## Design section into ## Tasks.
3. Retire obra/superpowers-style external dependencies and migrate any remaining high-value external specs into roadmap or reference pages.

Related work

• Research: Spec-driven workflow: prior art and alternatives — why obra/superpowers, OpenSpec, and gotalab/cc-sdd were mined but not adopted wholesale.