Direct USDC Generate


POST /api/proxy-generate

Generate AI content by submitting proof of a direct USDC transfer on Base. Use this when you can’t use the X402 protocol (e.g., from Python or environments without x402-fetch).

Flow

Transfer USDC to the gateway wallet on Base
Submit the transaction hash with your generation request
The server verifies the on-chain payment
Generation starts and you get a task ID to poll

Request Body


{
  "slug": "nano-banana",
  "prompt": "A photorealistic sunset over the ocean",
  "txHash": "0xabc123def456...",
  "aspect_ratio": "16:9",
  "output_format": "webp"
}

Field	Type	Required	Description
`slug`	string	Yes	Endpoint identifier
`prompt`	string	Conditional	Generation prompt (1–10,000 chars). Required unless `fileBase64` is provided.
`txHash`	string	Yes	Transaction hash (`0x` + 64 hex characters)
`fileBase64`	string	No	Base64-encoded file for document parsing (max ~7.5 MB)
`fileName`	string	No	Original filename (required if `fileBase64` is provided)
`aspect_ratio`	string	No	Image ratio: `1:1`, `4:3`, `3:4`, `16:9`, `9:16`
`output_format`	string	No	Output format: `png`, `jpg`, `webp`
`resolution`	string	No	Output resolution (provider-dependent)

Response — 200 Success


{
  "success": true,
  "taskId": "a1b2c3d4-e5f6-7890-abcd-ef1234567890",
  "statusUrl": "/api/task/a1b2c3d4-e5f6-7890-abcd-ef1234567890",
  "paidAmount": 0.05,
  "message": "Generation started. Poll statusUrl for results."
}

Error Responses

Status	Code	Description
400	`VALIDATION_ERROR`	Invalid request body (missing fields, bad format)
400	`TX_NOT_FOUND`	Transaction hash not found on Base network
400	`TX_FAILED`	Transaction failed on-chain
400	`INVALID_PAYMENT`	No USDC transfer to gateway wallet in the transaction
400	`INSUFFICIENT_PAYMENT`	Amount transferred is less than endpoint price
400	`TX_ALREADY_USED`	This transaction hash has already been submitted
404	`NOT_FOUND`	Endpoint slug does not exist
429	—	Rate limited (5 req/min)
500	`INTERNAL_ERROR`	Failed to create task record
500	`EXECUTION_ERROR`	Generation failed server-side

Payment Verification

The server verifies your transaction on-chain:

Fetches the transaction receipt from Base
Looks for a USDC Transfer event where the recipient matches the gateway wallet
Checks the transferred amount is at least the endpoint price
Ensures the transaction hash hasn’t been used before (replay protection)

USDC Contract on Base: 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 (6 decimals)

Example


# After transferring 0.05 USDC to the gateway wallet on Base:
curl -X POST https://402claw.cloud/api/proxy-generate \
  -H "Content-Type: application/json" \
  -d '{
    "slug": "nano-banana",
    "prompt": "A beautiful mountain landscape at golden hour",
    "txHash": "0x1234567890abcdef1234567890abcdef1234567890abcdef1234567890abcdef"
  }'

File Upload Example


# Base64-encode a PDF and submit for parsing:
FILE_B64=$(base64 -i document.pdf)
 
curl -X POST https://402claw.cloud/api/proxy-generate \
  -H "Content-Type: application/json" \
  -d "{
    \"slug\": \"llamaparse\",
    \"fileBase64\": \"$FILE_B64\",
    \"fileName\": \"document.pdf\",
    \"txHash\": \"0x...\"
  }"