# License Compatibility Checker

> License Compatibility Checker is a paid API for AI agents from defi-shield-hazel.vercel.app, paid per call via x402, $0.05/call, status unknown (last checked 2026-09-16).

Checks npm package licenses for copyleft/restrictive conflicts by performing real npm registry lookups and detecting incompatible license combinations

## Facts

- Endpoint: POST https://defi-shield-hazel.vercel.app/api/dev/license-check
- Price: $0.05/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-16
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/defi-shield-hazel-vercel-app-6cf47faf
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_kg_ObZtizj7LP5zGu66-a

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability defi-shield-hazel-vercel-app-6cf47faf -d '<json body>'
```

Example prompt: Can you check whether the npm package 'react-query' has any copyleft or restrictive license conflicts that would prevent me from using it in a closed-source commercial app?

## When to prefer this

Use this endpoint when you need to programmatically verify open-source license compatibility for npm packages before including them in a project, especially to detect copyleft (GPL, AGPL, LGPL) or other restrictive licenses that could create compliance obligations in commercial or proprietary software.

## Known failure modes

- Package not found on npm registry — returns 404 or error indicating unknown package
- Network timeout reaching npm registry — returns upstream error
- Invalid or malformed package name — returns validation error
- Package has no declared license — returns ambiguous/unlicensed flag
- Rate limit or payment failure — returns 402 or 429 error

## Output

Returns the license type(s) found for the specified npm package(s) via real registry lookup, along with compatibility assessment, copyleft/restrictive conflict flags, and a summary of any licensing issues detected.

## Example request

```json
{
 "input": {
  "body": {
   "dependencies": [
    "lodash",
    "axios"
   ],
   "project_license": "MIT"
  },
  "type": "http",
  "method": "POST",
  "bodyType": "json"
 }
}
```

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "bodyType",
    "body",
    "method"
   ],
   "properties": {
    "body": {
     "properties": {
      "dependencies": {
       "type": "array",
       "description": "Array of npm package names to check"
      },
      "project_license": {
       "type": "string",
       "description": "Your project's license (default: MIT)"
      }
     }
    },
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "POST"
     ],
     "type": "string"
    },
    "bodyType": {
     "enum": [
      "json",
      "form-data",
      "text"
     ],
     "type": "string"
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/defi-shield-hazel-vercel-app-6cf47faf/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from defi-shield-hazel.vercel.app](https://www.zero.xyz/host/defi-shield-hazel.vercel.app/llms.txt)