10ximplement

10ximplement is a Codex skill for long-running implementation work that needs more structure than a single prompt.

It combines four habits into one workflow:

• keep a durable implementation ledger
• choose narrow PM-style phase gates
• execute plans with subagents and review loops when available
• fall back to sequential plan execution when subagents are not the right fit

The key artifact is implementation-notes.html: a readable run ledger that tracks resume state, phase gates, decisions and the logic behind them, validation, blockers, accepted defers, evidence, and the next exact action.

Install

Clone this repo directly into your Codex skills folder:

git clone https://github.com/cobibean/10ximplement.git ~/.codex/skills/10ximplement

Then invoke it in Codex:

Use $10ximplement to run this build through phase gates, subagent execution, review checkpoints, and a durable implementation ledger.

What It Adds

10ximplement is built for work where agents usually lose the plot:

• multi-phase builds
• plans that need review gates
• subagent-heavy implementation
• long context windows and compaction risk
• decisions that need to survive handoff
• "continue where we left off" sessions

The skill creates this structure inside the target project:

.agent/
  GOALS.md
  runs/
    <goal-id>/
      GOAL.md
      implementation-notes.html
      evidence/

GOAL.md is the contract. implementation-notes.html is the live state and history. evidence/ stores bulky logs, screenshots, reports, or command output that should not clog the HTML.

Start A Ledger

The skill ships a helper script:

python3 ~/.codex/skills/10ximplement/scripts/init_10x_ledger.py \
  --root . \
  --goal-id "my-feature" \
  --title "My Feature" \
  --objective "Ship the feature through reviewed phase gates." \
  --mode full

The script uses assets/implementation-notes.template.html, so agents do not need to recreate the ledger UI from memory.

Workflow

At a high level, the agent:

1. Loads repo/spec context and checks current worktree state.
2. Creates or resumes the .agent/runs/<goal-id>/ ledger.
3. Chooses one narrow implementation phase.
4. Asks for PM/review mode at phase boundaries when needed.
5. Executes through subagents, sequential plan steps, or a PM handoff.
6. Runs review gates before accepting the checkpoint.
7. Updates implementation-notes.html with decisions, logic, validation, defers, blockers, and next action.
8. Finishes only after checking GOAL.md finishing criteria.

Source Lineage

This skill synthesizes ideas from:

• Goal Ledger: local custom skill for .agent/runs/<goal-id>/GOAL.md and implementation-notes.html
• Product Manager Phase Gates: local custom skill for PM modes, review modes, narrow slices, and checkpoint verdicts
• executing-plans
• subagent-driven-development

It also inherits useful surrounding practices from the Superpowers ecosystem:

• using-git-worktrees
• writing-plans
• requesting-code-review
• finishing-a-development-branch

Files

• SKILL.md: main skill instructions
• assets/implementation-notes.template.html: run ledger template
• scripts/init_10x_ledger.py: ledger initializer
• references/subagent-prompts.md: compact subagent prompt guidance
• agents/openai.yaml: Codex UI metadata

License

MIT