curl --request POST \
  --url https://api.iotools.cloud/v1/tool/websocket-frame-decoder \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "frameInput": "81 05 48 65 6c 6c 6f"
}
'

{
  "tool": "websocket-frame-decoder",
  "tool_version": "1.0.2",
  "outputs": {
    "fields": [
      {
        "field": "FIN",
        "value": "1 (final frame)"
      },
      {
        "field": "RSV1 / RSV2 / RSV3",
        "value": "0 / 0 / 0"
      },
      {
        "field": "Opcode",
        "value": "0x1 — Text"
      },
      {
        "field": "MASK",
        "value": "0 (unmasked)"
      },
      {
        "field": "Payload Length field",
        "value": "5 (7-bit form)"
      },
      {
        "field": "Actual Payload Length",
        "value": "5 bytes"
      },
      {
        "field": "Masking Key",
        "value": "— (not masked)"
      },
      {
        "field": "Total Frame Length (received)",
        "value": "7 bytes"
      },
      {
        "field": "Warnings",
        "value": "None"
      }
    ],
    "structure": [
      {
        "offset": "0",
        "bytes-hex": "81",
        "part": "FIN/RSV1-3/Opcode",
        "decoded": "10000001 → FIN=1 RSV=000 opcode=0x1 — Text"
      },
      {
        "offset": "1",
        "bytes-hex": "05",
        "part": "MASK/Payload len",
        "decoded": "00000101 → MASK=0 len=5"
      },
      {
        "offset": "2-6",
        "bytes-hex": "48 65 6c 6c 6f",
        "part": "Payload data (5 bytes)",
        "decoded": "48 65 6c 6c 6f"
      }
    ],
    "payload": [
      {
        "field": "Payload (hex)",
        "value": "48 65 6c 6c 6f"
      },
      {
        "field": "Decoded Text",
        "value": "Hello"
      }
    ],
    "jsonOutput": "{\n  \"fin\": true,\n  \"rsv1\": false,\n  \"rsv2\": false,\n  \"rsv3\": false,\n  \"opcode\": 1,\n  \"opcodeName\": \"Text\",\n  \"masked\": false,\n  \"payloadLengthForm\": \"7-bit\",\n  \"payloadLength\": 5,\n  \"maskingKeyHex\": null,\n  \"totalFrameLength\": 7,\n  \"payloadHexUnmasked\": \"48 65 6c 6c 6f\",\n  \"decodedText\": \"Hello\",\n  \"close\": null,\n  \"warnings\": []\n}"
  },
  "credits_used": 5,
  "credits_remaining": null
}