loop-engineering

A design guide for building an autonomous coding workflow that repeatedly discovers work, assigns it to a coding agent, checks the result, records progress, and decides when to stop.

In plain words
What is it for?
It helps scaffold recurring development workflows involving task discovery, separate implementation and checking roles, saved state, verification, and automatic continuation.
Why use it?
It reduces the need to keep prompting an agent by hand while keeping progress and stop conditions visible. It is intended to stop when a clear, machine-checkable success condition is met.

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/invincible04/awesome-loop-engineering/loop-engineering
Any agent
npx skills add invincible04/awesome-loop-engineering --skill loop-engineering
Clone the repo
git clone --depth 1 https://github.com/invincible04/awesome-loop-engineering

Made for: Claude Code, Codex.

Per session 150 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 3,414 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 $0.00150 $0.03414
Opus 5 $0.00075 $0.01707
Sonnet 5 $0.00030 $0.00683
Haiku 4.5 $0.00015 $0.00341

Measured 2d ago against content hash 35c2753e23cc, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

loop-engineering 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.

skill/loop-engineering/SKILL.md · 239 lines

How it starts

The opening of the file, as written. The whole thing — 239 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Loop Engineering

Help the user replace themselves as the thing that prompts a coding agent. The deliverable is a small system that discovers work, hands it to a maker, verifies the result with a separate checker, writes down what is done, decides what is next, and re-runs until a goal is met, then stops for an honest reason.

Your job in this skill is not to write the loop for them in one shot. It is to interview, design the contract, then scaffold so they end with a loop they can actually run and trust.

What a loop is, and is not

A loop is not a cron job. A cron job repeats blindly. A loop discovers work, verifies it with a separate checker, persists state, decides what is next, and stops for a reason. If the thing you are building cannot stop on its own, it is a bug, not a loop.

Build stop conditions first. They are what let the user walk away.

Step 0: decide whether a loop is even the right tool

Before designing anything, apply this test. A loop pays off only when both are true:

  1. There is a clear, machine-checkable success criterion (a test passes, a build is green, a schema validates, a rubric returns PASS).
  2. Reaching it involves tedious trial and error the user would otherwise do by hand, turn after turn.

If the user cannot state how a machine would know the work is done, stop and say so. A loop with no verifiable done-condition does not converge; it thrashes and burns tokens. Help them find a checkable proxy first, or recommend they keep prompting by hand. Do not build a loop to avoid understanding the work.

Two more preconditions the test assumes: the work recurs often enough to amortize the loop's fixed cost (a rough floor is weekly; if it is rarer, write a script, not a loop), and the agent has an engineer's tools to get unstuck on its own (read logs, reproduce a failure, run its own code). If a check exists in principle but the agent cannot run it, you have a human relay, not a loop yet.

Good loop candidates: fixing failing CI, triaging an issue inbox, dependency upgrades against a solid test suite, performance tuning with a benchmark, flaky test hunts, doc builds that must stay green. Poor candidates: open-ended design, anything where "good" is a matter of taste with no proxy, one-off tasks.

Read the full file on GitHub · 239 lines

Files

What ships with it

7 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

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 · 239 lines · 150 tokens per session scan A 35c2753e23cc

Subscribe to this mod's changes

loop-engineering is a skill published in the GitHub repository invincible04/awesome-loop-engineering (54 stars, last pushed 2mo ago), licensed MIT. It adds 150 tokens to every session and 3,414 once invoked, about $0.0007 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 2026-08-30.

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