loop

A seven-phase workflow for handling non-trivial software changes from understanding the problem through reflection after delivery.

In plain words
What is it for?
Use it to think through a change, plan and build it, review the code, test the result, ship it, and reflect on the outcome.
Why use it?
It reduces skipped planning, hidden assumptions, unreviewed changes, and untested work.

Skill for Claude CodeCodex

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add skills/abstractonion/cadence/loop
Any agent
npx skills add abstractonion/cadence --skill loop
Clone the repo
git clone --depth 1 https://github.com/abstractonion/cadence

Made for: Claude Code, Codex.

Per session 33 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 507 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00033 $0.00507
Opus 5 $0.00016 $0.00253
Sonnet 5 $0.00007 $0.00101
Haiku 4.5 $0.00003 $0.00051

Measured 2d ago against content hash 12767a74cc80, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

loop scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 2d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

plugins/cadence/skills/loop/SKILL.md · 21 lines

What it actually says

The Engineering Loop

Every non-trivial change moves through seven phases. Skipping a phase is a choice — name which one and why.

  1. Think — restate the problem before touching code. Who is this actually for? What's the smallest version that delivers value? What is the user already doing as a workaround? See propose-then-implement.
  2. Plan — pick an approach with eyes open. Note data flow, edge cases, failure modes, and the tests that would prove it works. Surface hidden assumptions instead of guessing past them. See scope-and-dispatch for parent routing before subagent fan-out. Single-thread decomposition: break-work-into-verifiable-steps or /plan. Multi-workstream coordination (disjoint scopes, explicit dependencies): delegate to cadence-planner, then partition fan-out per parallel-workstreams.
  3. Build — implement with the smallest diff that cleanly expresses the change. Don't refactor adjacent code unless the structural fix is the whole point.
  4. Review — read your own diff like a stranger before handing it off. See self-review-before-handoff.
  5. Test — verify against reality, not intent. Return the evidence bundle per verify-with-runtime (library: test_name + red/green output; UI: flow + console; API/CLI: exit_code + output; blocked: blocked_reason). Stale evidence from earlier in the session does not count.
  6. Ship — clean commits, accurate description, fresh evidence at the moment of push. See clean-commits. When a PR already exists for this branch, hand off ongoing settle to /own-pr (cadence-own-pr) instead of a one-shot push-and-exit.
  7. Reflect — name one durable lesson before moving on. See capture-learnings.

When a bug shows up, the loop is the same — Think (what is actually happening?) → Plan (one hypothesis at a time) → Build (smallest fix) → Review/Test/Ship/Reflect. See investigate-before-fixing for the bug-specific gates.

The cost of doing the complete thing is much lower than it used to be. Default to it.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 2d ago First seen · 21 lines · 33 tokens per session scan A 12767a74cc80

Subscribe to this mod's changes

loop is a skill published in the GitHub repository abstractonion/cadence (4 stars, last pushed 2mo ago), licensed MIT. It adds 33 tokens to every session and 507 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.

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