Readme Min Line Count + README Collector

✓ Guardrail ↓ Collector Stable Repository And Ownership

Enforce Readme Min Line Count using data collected by README Collector. Automatically check repository and ownership standards on every PR.

Guardrail: Requires the README to have a minimum number of lines (default 25). Prevents placeholder READMEs that lack useful information.

Data Source: Verify README files exist and analyze their structure including line count and section headings. Enforce documentation standards across your repositories.

Get Started View on GitHub

How README Collector Powers This Guardrail

The README Collector gathers metadata from your documentation systems. This data flows into Lunar's Component JSON, where the Readme Min Line Count guardrail evaluates it against your standards.

When enabled, this check runs automatically on every PR and in AI coding workflows, providing real-time enforcement with actionable feedback.

↓ README Collector Gathers Data Collector

Extracts metadata from code, configs, and tool outputs

{ } Component JSON

Data centralized in structured format for evaluation

✓ Readme Min Line Count Checks Guardrail

Pass/fail result with actionable feedback in PRs

Quick Start Configuration

Add both the collector and policy to your lunar-config.yml to enable this guardrail.

📄 lunar-config.yml

# Step 1: Enable the README Collector
collectors:
  - uses: github://earthly/lunar-lib/collectors/readme@v1.0.0
    # with: ...

# Step 2: Enable the README Guardrails
policies:
  - uses: github://earthly/lunar-lib/policies/readme@v1.0.0
    include: [readme-min-line-count]
    # with: ...

What README Collector Collects

This collector gathers the following data that the Readme Min Line Count guardrail evaluates.

Collector code

`readme`

Scans repository root for README files (README.md, README, README.txt, README.rst) in order, taking the first match. Extracts line count and section headings by parsing markdown headers. Writes exists, path, lines, and sections to .repo.readme.

Example Data Flow

Here's an example of the data that README Collector writes to the Component JSON, which Readme Min Line Count then evaluates.

{ } component.json From README Collector

{
  "repo": {
    "readme": {
      "exists": true,
      "path": "README.md",
      "lines": 150,
      "sections": [
        "Installation",
        "Usage",
        "API",
        "Contributing",
        "License"
      ]
    }
  }
}

Configuration Options

README Collector Inputs

Input	Required	Default	Description
`paths`	Optional	`README.md,README,README.txt,README.rst`	Comma-separated list of README paths to check (first match wins)

README Guardrails Inputs

Input	Required	Default	Description
`min_lines`	Optional	`25`	Minimum number of lines required in README file
`required_sections`	Required	—	Comma-separated list of required sections in README file

Learn More

Guardrail · README Guardrails Readme Min Line Count View all compatible integrations

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Collector README Collector View full documentation

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