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LaunchGuard

Catch missing plugins, commands, worlds, unsafe locations, and basic permission issues before players join.

LaunchGuard v1.0.0 Documentation

LaunchGuard is a read-only pre-launch diagnostic plugin for Paper servers.

Current stable release: v1.0.0 Previous marketplace stable release: v0.5.0

LaunchGuard helps server owners check launch-readiness before opening a server to players. It focuses on configured checks, reports, exports, configuration validation, plugin visibility, and baseline drift detection.

LaunchGuard does not fully test plugin behavior and does not verify plugin runtime correctness.

Installation

Download LaunchGuard-1.0.0.jar.
Put the JAR file into your Paper server’s plugins/ folder.
Restart the server.
Run:

/launchguard version
/launchguard validate
/launchguard run

Recommended first check:

/launchguard validate

This checks LaunchGuard configuration files for common mistakes before you rely on reports.

Basic Usage

Run a pre-launch check:

/launchguard run

View the latest saved report:

/launchguard history latest

Export the current check as JSON:

/launchguard export json

Export the current check as HTML:

/launchguard export html

Validate configuration files:

/launchguard validate

Main Commands

/launchguard help
/launchguard version
/launchguard run
/launchguard reload
/launchguard plugins
/launchguard plugins verbose
/launchguard plugins dependencies
/launchguard history
/launchguard history latest
/launchguard export json
/launchguard export html
/launchguard validate

Baseline Commands

Baselines let you save a known-good server state and compare future states against it.

Save a baseline:

/launchguard baseline save production

List baselines:

/launchguard baseline list

Compare against a baseline:

/launchguard baseline compare production

Compare and save a text report:

/launchguard baseline compare production save

Export baseline comparison as JSON:

/launchguard baseline export json production

Export baseline comparison as HTML:

/launchguard baseline export html production

View baseline report history:

/launchguard baseline history
/launchguard baseline history latest

Delete a baseline:

/launchguard baseline delete production

Baseline names must use 1–32 characters and may contain only letters, numbers, underscores, and dashes. Do not use spaces, dots, slashes, file extensions, or path-like names.

Configuration Files

LaunchGuard uses local configuration files inside:

plugins/LaunchGuard/

Main configuration areas include:

report output
startup run settings
saved report retention
export retention
baseline report retention
optional startup baseline comparison

Important settings include:

settings:
  showPassedChecks: true
  reportToConsole: true
  runOnStartup: false
  startupDelayTicks: 100
  saveReports: true
  reportsToKeep: 10
  exportsToKeep: 25
  baselineReportsToKeep: 25
  compareBaselineOnStartup: false
  startupBaselineName: "production"
  startupBaselineSaveReport: true
  startupBaselineDelayTicks: 120

After editing configuration files, run:

/launchguard validate
/launchguard reload

Optional Startup Baseline Compare

Startup baseline comparison is disabled by default.

Enable it with:

settings:
  compareBaselineOnStartup: true
  startupBaselineName: "production"
  startupBaselineSaveReport: true
  startupBaselineDelayTicks: 120

When enabled, LaunchGuard waits for the configured delay, loads the selected baseline, compares the current server state, prints the result to console, and optionally saves a local text report.

Startup baseline comparison does not stop, restart, block, or modify the server.

Local File Locations

LaunchGuard writes only inside its own plugin folder.

plugins/LaunchGuard/reports/
plugins/LaunchGuard/exports/
plugins/LaunchGuard/baselines/
plugins/LaunchGuard/reports/baseline/

File types:

Preflight reports: .txt
Exports: .json, .html
Baselines: .yml
Baseline reports: .txt

Permissions

launchguard.use
launchguard.run
launchguard.reload
launchguard.plugins
launchguard.history
launchguard.export
launchguard.validate
launchguard.baseline
launchguard.admin

launchguard.admin includes all LaunchGuard child permissions.

Compatibility

Fully smoke-tested:

Paper 1.20.1 through 1.20.6
Paper 1.21.1 through 1.21.10

Load-tested only:

Paper 1.21.11

Not available on PaperMC at QA time:

26.1
26.2

Not tested:

26.3

Paper 1.21.11 is load-tested only and is not claimed as fully smoke-tested.

Use the Java version required by your Paper server version.

Safety

LaunchGuard is read-only.

It does not:

execute configured commands
modify server state
send network calls
install plugins
download plugins
enable or disable plugins
reload other plugins
teleport players
modify blocks
modify worlds
modify economy data
modify permission data
change whitelist state
force-load chunks
stop the server
restart the server
block server startup

LaunchGuard is a diagnostic and reporting tool. It is not a replacement for manual server testing.

Pages

Resource Page

Documentation