# License Intel – SPDX License Expression Validator

> License Intel – SPDX License Expression Validator is a paid API for AI agents from license-intel.x402tookit.com, paid per call via x402, $0.03/call, status unknown (last checked 2026-10-30).

Validates an SPDX license expression (with AND, OR, WITH, + operators) for syntax correctness, known license IDs, known exceptions, and deprecated identifiers.

## Facts

- Endpoint: GET https://license-intel.x402tookit.com/license-expression-check?utm_source=zero.xyz
- Price: $0.03/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-30
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/license-intel-spdx-license-expression-validator-9858961c
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_Ua7KX2hsQHu_fTjciAyWg

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 license-intel-spdx-license-expression-validator-9858961c
```

Example prompt: Can you check whether the SPDX license expression 'MIT OR (Apache-2.0 AND BSD-3-Clause)' is valid — confirm the syntax is correct, all the license IDs are known, and nothing is deprecated?

## When to prefer this

Choose this endpoint when you need to validate a full SPDX compound expression (using AND, OR, WITH, or + operators) rather than checking a single license ID in isolation. It is the right choice for CI/CD pipelines, package publishing workflows, or legal compliance checks where the expression structure and operator semantics matter, not just whether individual IDs exist. Use the sibling lookup endpoints for single-ID metadata or plain-language explanations.

## Known failure modes

- Missing 'expression' query parameter returns an error
- Malformed SPDX syntax returns a verdict of invalid with reasons explaining the parse failure
- Unknown license IDs are flagged in the license list with status 'unknown' rather than causing a hard error
- Deprecated license IDs are flagged but may still return a valid parse if syntax is correct
- Network or upstream SPDX data unavailability may return a degraded flag with partial results

## How this service works

Validate an SPDX license expression (AND, OR, WITH, +): syntax, known ids, known exceptions and deprecated identifiers.

## Output

Returns a structured JSON object containing: a verdict (valid/invalid), a human-readable summary, an array of reasons explaining any issues, a list of parsed license objects (each with id, name, status, canonicalId, OSI-approved flag, and whether + was used on a deprecated ID), a list of exception objects, the list of operators found, any warnings, the SPDX list version used, data freshness timestamp, and source attribution.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "expression"
     ],
     "properties": {
      "expression": {
       "type": "string",
       "description": "An SPDX expression, for example MIT OR (Apache-2.0 AND BSD-3-Clause)"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "properties": {
      "asOf": {
       "type": [
        "null",
        "string"
       ]
      },
      "source": {
       "type": [
        "null",
        "string"
       ]
      },
      "reasons": {
       "type": [
        "array",
        "null"
       ],
       "items": {
        "type": "string"
       }
      },
      "summary": {
       "type": [
        "null",
        "string"
       ]
      },
      "verdict": {
       "type": [
        "null",
        "string"
       ]
      },
      "degraded": {
       "type": [
        "boolean",
        "null"
       ]
      },
      "licenses": {
       "type": [
        "array",
        "null"
       ],
       "items": {
        "type": "object",
        "properties": {
         "id": {
          "type": [
           "null",
           "string"
          ]
         },
         "name": {
          "type": [
           "null",
           "string"
          ]
         },
         "status": {
          "type": [
           "null",
           "string"
          ]
         },
         "canonicalId": {
          "type": [
           "null",
           "string"
          ]
         },
         "osiApproved": {
          "type": [
           "boolean",
           "null"
          ]
         },
         "plusOnDeprecated": {
          "type": [
           "boolean",
           "null"
          ]
         }
        }
       }
      },
      "warnings": {
       "type": [
        "array",
        "null"
       ]
      },
      "operators": {
       "type": [
        "array",
        "null"
       ],
       "items": {
        "type": "string"
       }
      },
     
… (truncated)
```

## More

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