# FastX402 Lab – Hash Digest

> FastX402 Lab – Hash Digest is a paid API for AI agents from fastx402.tools, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-17).

Computes SHA-1, SHA-256, SHA-384, or SHA-512 cryptographic digest of UTF-8 text, returning the result as hex or Base64

## Facts

- Endpoint: GET https://fastx402.tools/hash-digest?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-17
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/fastx402-lab-hash-digest-9b1c37e2
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_qFsFU1XyVMYRSZkfVaBYz

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 fastx402-lab-hash-digest-9b1c37e2
```

Example prompt: Hash the text 'Hello, world!' using SHA-256 and give me the result as a hex digest.

## When to prefer this

Use this endpoint when you need a fast, serverless cryptographic hash of a UTF-8 string without setting up local crypto libraries — ideal for AI agents needing checksums, SRI values, cache keys, or hash verification in a pay-per-call context via x402.

## Known failure modes

- Missing required 'text' query parameter returns an error
- Unsupported algorithm or encoding enum value returns a validation error
- Extremely large text inputs may exceed request size limits
- Payment failure (x402) if USDC balance is insufficient

## How this service works

146 pay-per-call tools for AI agents, from $0.001 per request in USDC on Base or Solana with x402. No account, no API key.

## Output

A JSON object containing the computed digest string (in hex or base64), the algorithm used, the encoding format, and the number of UTF-8 bytes in the input text.

## 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": [
      "text"
     ],
     "properties": {
      "text": {
       "type": "string",
       "description": "Text to hash (UTF-8)"
      },
      "encoding": {
       "enum": [
        "hex",
        "base64"
       ],
       "type": "string",
       "description": "hex or base64 (default hex)"
      },
      "algorithm": {
       "enum": [
        "sha1",
        "sha256",
        "sha384",
        "sha512"
       ],
       "type": "string",
       "description": "sha1, sha256, sha384 or sha512 (default sha256)"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "properties": {
      "digest": {
       "type": "string"
      },
      "encoding": {
       "type": "string"
      },
      "algorithm": {
       "type": "string"
      },
      "input_bytes": {
       "type": "integer"
      }
     }
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "digest": "b94d27b9934d3e08a52e52d7da7dabfac484efe37a5380ee9088f7ace2efcde9",
  "encoding": "hex",
  "algorithm": "sha256",
  "input_bytes": 11
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/fastx402-lab-hash-digest-9b1c37e2/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from fastx402.tools](https://www.zero.xyz/host/fastx402.tools/llms.txt)