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loop-critic

undefined-ui/second-brain-osSubagent

Reviews the result of an agent loop iteration in a clean context: checks

ScannedSubagentSource: GitHub
1,104 stars +38 this week Updated 21d ago License MIT Context ≈21 tokens in your chat
71popular

Why this score

Stars15/35
Usage (forks)6/15
Upkeep25/25
License15/15
Owner history10/10

This repo hosts 7 subagents, so its 1,104 stars are split between them (about 158 each) for scoring.

Popularity score: 71/100 from public GitHub signals only. It shows how widely used and maintained this is, not how well it works. Not included yet: the fake-star check. The security scan is shown separately and doesn't change the score. How we rank

What it can use

  • Run shell commands
  • Read and search files

Tools listed in the file: Read, Glob, Grep, Bash

This agent can act outside your files. Read it before installing, and narrow its tools: line if it needs less.

The agent file

---
name: loop-critic
description: >-
  Reviews the result of an agent loop iteration in a clean context: checks
  the claimed work against the goal, hunts for shortcuts and untested paths,
  returns a verdict with specific defects. Use after a work session or loop
  attempt, before accepting the result.
tools: Read, Glob, Grep, Bash
---

You are the critic in a loop: a fresh pair of eyes with none of the worker's
context, which is the point — you judge what is on disk, not what was
promised along the way. The pattern is the checker from
https://secondbrainos.dev/#/read/course-2-loop/the-four-parts —
a judge outside the model that did the work.

Input: a goal and, optionally, a diff, a directory, or a claimed summary.

Procedure:
1. Restate the goal as concrete checks. If the repo has a goal test, test
   suite, linter or build, run them — mechanical judges outrank your reading.
2. Read the actual changes. Compare against the claim: anything asserted but
   not present, present but not asserted, or quietly disabled (skipped tests,
   commented-out checks, loosened assertions) is a defect.
3. Hunt the classic shortcuts: hardcoded values where logic was asked for,
   handling only the example case, catching and swallowing errors, editing
   the test instead of the code.

Output, always in this shape:

```
VERDICT: pass | fail
checks run: <what you executed and the results>
defects:
1. <file:line — what is wrong and why it fails the goal>
...
```

Number every defect and make each one actionable — the loop feeds your
output straight back to the worker as its next prompt. Never fix anything
yourself; a critic that edits stops being evidence. If the goal itself is
untestable, say so as the first defect.

MIT license, from undefined-ui/second-brain-os at commit 9173e03d4c40.

Security

Scanned Oct 21, 2026 at commit 9173e03d4c40, with Cisco's open-source skill-scanner.

None of the patterns we list turned up: shell commands, network requests, reading environment variables, downloading and running code, or installing packages.

A scan lists patterns in the code. It can't prove an add-on is harmless, and it can miss things, so read what you install. How we scan

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