loop-engineer

An improvement workflow for an app after launch. It checks the app’s current state, ranks what to build next using data, and supervises the build, testing, and recommendation cycle.

In plain words
What is it for?
Use it to rank feature ideas, plan the next sprint, assess an existing app, or run a repeated improvement process.
Why use it?
It helps teams decide what to improve next instead of choosing features without checking evidence. It also keeps development and validation connected in a repeating cycle.

Agent for Claude Code

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 agents/seungmanchoi/react-native-fsd-agent-template/loop-engineer
Clone the repo
git clone --depth 1 https://github.com/seungmanchoi/react-native-fsd-agent-template

Made for: Claude Code.

Per session 106 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 2,516 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin unknown 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 $0.00106 $0.02516
Opus 5 $0.00053 $0.01258
Sonnet 5 $0.00021 $0.00503
Haiku 4.5 $0.00011 $0.00252

Measured 2d ago against content hash 232744de82d5, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

loop-engineer 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.

.claude/agents/loop-engineer.md · 121 lines

The source is not reproduced here

No licence file

A repository with no LICENSE is all rights reserved by default, so the body is not copied here. The metadata, the measurements and the link are.

Read it on GitHub

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 · 121 lines · 106 tokens per session scan A 232744de82d5

Subscribe to this mod's changes

loop-engineer is an agent published in the GitHub repository seungmanchoi/react-native-fsd-agent-template (49 stars, last pushed 1mo ago), with no licence file. It adds 106 tokens to every session and 2,516 once invoked, about $0.0005 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.