Challenge Pack Schema

The Challenge Pack Schema defines a collection of related challenges. It allows you to group multiple challenge bundles together, specify their relationships, and override individual challenge properties.

Basic Structure

{
  "$schema": "https://raw.githubusercontent.com/durkinza/challenge-bundle-schema/main/challenge-pack.schema.json",
  "challenges": [
    {
      "id": "intro-challenge",
      "path": "./challenges/intro",
      "category": "web",
      "points": 100
    },
    {
      "id": "advanced-challenge",
      "path": "./challenges/advanced",
      "category": "web",
      "points": 250,
      "prerequisites": ["intro-challenge"]
    }
  ]
}

Required Fields

Field	Type	Description
challenges	array	Array of challenge objects defining the challenges in this pack

Challenge Object Fields

Each challenge in the challenges array must have:

Field	Type	Required	Description
id	string	Yes	Unique identifier for this challenge within the pack
path	string	Yes	Path to the directory containing the challenge bundle (relative to the challenge-pack.json file)
category	string	No	Override the category from the challenge.json. If not provided, uses the challenge's default category
points	number	No	Override the point value from the challenge.json. If not provided, uses the challenge's default points
prerequisites	string[]	No	Array of challenge IDs that must be solved before this challenge becomes available

Pack Structure

A challenge pack bundle is a .zip file containing:

my-challenge-pack.zip
├── challenge-pack.json
├── web-basics.zip
│   ├── challenge.json
│   └── src/
├── crypto-intro.zip
│   ├── challenge.json
│   └── build.sh
└── forensics-101.zip
    ├── challenge.json
    └── evidence.pcap

Path Resolution

Paths in the path field are resolved relative to the location of challenge-pack.json:

{
  "challenges": [
    {
      "id": "challenge1",
      "path": "./web-basics.zip"           // Looks for ./web-basics.zip/challenge.json
    },
    {
      "id": "challenge2",
      "path": "./crypto-intro.zip"  // Looks for ./crypto-intro.zip/challenge.json
    },
    {
      "id": "challenge3",
      "path": "./forensics-101.zip"  // Looks for ./forensics-101.zip/challenge.json
    }
  ]
}

Prerequisites System

The prerequisites field creates dependencies between challenges:

{
  "challenges": [
    {
      "id": "challenge1",
      "path": "./web-basics.zip"
      // No prerequisites - available immediately
    },
    {
      "id": "challenge2",
      "path": "./crypto-intro.zip",
      "prerequisites": ["challenge1"]  // Unlocks after completing challenge1
    },
    {
      "id": "challenge3",
      "path": "./forensics-101.zip",
      "prerequisites": ["challenge1", "challenge2"]  // Requires both challenge1 AND challenge2
    }
  ]
}

How Prerequisites Work

1. Challenges without prerequisites are available immediately
2. Challenges with prerequisites are locked until all prerequisite challenges are solved
3. Prerequisites reference challenge id values, not paths
4. Multiple prerequisites create an AND relationship (all must be completed)
5. Circular dependencies are not allowed

Prerequisites must be supported by the CTF platform deploying the challenge pack to enforce these relationships.

Overriding Challenge Properties

You can override specific properties from individual challenge.json files:

Category Override

The pack's category takes precedence:

challenges/web-app/challenge.json:

{
  "name": "Cookie Monster",
  "category": "web",  // Original category
  "points": 100
}

challenge-pack.json:

{
  "challenges": [
    {
      "id": "cookie-monster",
      "path": "./challenges/web-app",
      "category": "input-validation"  // Overrides to "input-validation"
    }
  ]
}

Points Override

Useful for adjusting difficulty in the context of the pack:

challenge-pack.json:

{
  "challenges": [
    {
      "id": "easy-crypto",
      "path": "./crypto/caesar",
      "points": 50  // Easier in this pack
    },
    {
      "id": "hard-crypto",
      "path": "./crypto/rsa",
      "points": 500  // Much harder in this pack
    }
  ]
}