# agent402.tools Checksum

> agent402.tools Checksum is a paid API for AI agents from agent402.tools, paid per call via x402, $0.001/call, status unknown (last checked 2026-09-14).

Computes MD5, SHA-1, SHA-256, SHA-512, and CRC32 checksums of a string in a single API call

## Facts

- Endpoint: POST https://agent402.tools/api/checksum
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/agent402-tools-checksum-1d9fc0b7
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_Nq_K9PbTG6Yu9lOpYXjpw

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 agent402-tools-checksum-1d9fc0b7 -d '<json body>'
```

Example prompt: Can you compute the MD5, SHA-256, and SHA-512 checksums of this string for me: 'Hello, world!'

## When to prefer this

Choose this endpoint when you need multiple checksum formats simultaneously for a single string or payload, avoiding the overhead of calling five separate hashing tools. Ideal for integrity verification workflows that must satisfy multiple standards (e.g. both SHA-256 and MD5 consumers) or when auditing data against checksums of unknown algorithm.

## Known failure modes

- Input string exceeds 10MB limit — request rejected
- Empty or missing 'data' field — validation error returned
- Non-string input type — schema validation failure
- Payment not attached or insufficient — 402 Payment Required

## How this service works

Compute MD5, SHA-1, SHA-256, SHA-512, and CRC32 checksums of a string in a single call. Useful for verifying file or payload integrity across different checksum standards without needing five separate tools.

## Output

Returns MD5, SHA-1, SHA-256, SHA-512, and CRC32 hash values for the input string, all computed in a single response — allowing cross-standard integrity verification without multiple API calls.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "data": {
   "type": "string",
   "description": "The string to compute checksums for (max 10MB)"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "md5": "5eb63bbbe01eeed093cb22bb8f5acdc3",
  "sha1": "2aae6c35c94fcfb415dbe95f408b9ce91ee846ed",
  "crc32": "0d4a1185",
  "sha256": "b94d27b9934d3e08a52e52d7da7dabfac484efe37a5380ee9088f7ace2efcde9",
  "sha512": "309ecc489c12d6eb4cc40f50c902f2b4d0ed77ee511a7c7a9bcd3ca86d4cd86f989dd35bc5ff499670da34255b45b0cfd830e81f605dcf7dc5542e93ae9cd76f"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/agent402-tools-checksum-1d9fc0b7/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from agent402.tools](https://www.zero.xyz/host/agent402.tools/llms.txt)