# Judge0 via Locus x402 — List Languages

> Judge0 via Locus x402 — List Languages is a paid API for AI agents from judge0.x402.paywithlocus.com, paid per call via x402, $0.005/call, status unknown (last checked 2026-09-15).

Returns the list of all programming languages supported by the Judge0 code execution sandbox.

## Facts

- Endpoint: POST https://judge0.x402.paywithlocus.com/judge0/list-languages
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/judge0-via-locus-x402-list-languages-eb288171
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_ZHMMrrCao4lXdNhEzVdRZ

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 judge0-via-locus-x402-list-languages-eb288171 -d '<json body>'
```

Example prompt: Can you fetch the full list of programming languages supported by the Judge0 sandbox so I can find the right language ID to use when submitting code?

## When to prefer this

Use this endpoint when you need to discover available language IDs before submitting code to the Judge0 execution sandbox, or when building a UI that enumerates supported languages. Prefer this over hardcoding language IDs, since the supported set can evolve. This is a read-only, low-cost lookup call ideal as a prerequisite step in automated coding workflows.

## Known failure modes

- Payment failure — insufficient USDC balance or x402 payment not accepted, resulting in a 402 response
- Malformed request body — missing required 'input' fields causes a 4xx validation error
- Service unavailability — Judge0 backend is down, resulting in a 5xx error
- Timeout — sandbox infrastructure slow to respond, causing a timeout error

## How this service works

Locus public pay-per-use API

## Output

Returns a structured payload containing the list of all programming languages supported by the Judge0 sandbox, each entry including a numeric language ID and a display name (with version), enabling the caller to look up the correct ID before submitting code for execution. The response wraps the data under a 'data' key with payment and request metadata.

## 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",
    "bodyType",
    "body"
   ],
   "properties": {
    "body": {
     "type": "object",
     "properties": {},
     "additionalProperties": true
    },
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "POST"
     ],
     "type": "string"
    },
    "bodyType": {
     "enum": [
      "json",
      "form-data",
      "text"
     ],
     "type": "string"
    }
   },
   "additionalProperties": false
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "data": {},
  "payment": {
   "scheme": "exact",
   "settledUsdc": "0.001000",
   "authorizedMaxUsdc": "0.001000"
  },
  "request": {
   "id": "00000000-0000-4000-8000-000000000000",
   "statusUrl": "/requests/00000000-0000-4000-8000-000000000000"
  },
  "success": true
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/judge0-via-locus-x402-list-languages-eb288171/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from judge0.x402.paywithlocus.com](https://www.zero.xyz/host/judge0.x402.paywithlocus.com/llms.txt)