💧 Spraay — Payment Infrastructure for AI Agents

Spraay is the payment layer for autonomous AI agents. It enables batch crypto payments across 13+ chains, x402 micropayment gateway access (76+ paid endpoints), agent-to-agent USDC settlement, on-chain payroll, Bitcoin PSBT batch transactions, and robot task commissioning via the Robot Task Protocol (RTP).

Quick Setup

# Set the gateway URL (default public gateway)
export SPRAAY_GATEWAY_URL="https://gateway.spraay.app"

# Optional: set API key for authenticated access
export SPRAAY_API_KEY="your-key-here"

No wallet setup required for gateway calls — the x402 protocol handles payment negotiation automatically via USDC on Base.

Core Capabilities

1. Batch Payments (Smart Contract)

Send ETH or ERC-20 tokens to up to 200 recipients in a single transaction. Available on Base, Ethereum, Arbitrum, Polygon, BNB Chain, Avalanche, Unichain, Plasma, BOB, Solana, Bittensor, and Stacks.

Base contract: 0x1646452F98E36A3c9Cfc3eDD8868221E207B5eEC

When to use: User wants to pay multiple people at once, distribute tokens, run payroll, airdrop, or split payments.

# Example: batch payment via gateway
curl -X POST "$SPRAAY_GATEWAY_URL/api/payments/batch" \
  -H "Content-Type: application/json" \
  -d '{
    "chain": "base",
    "token": "USDC",
    "recipients": [
      {"address": "0xAAA...", "amount": "100"},
      {"address": "0xBBB...", "amount": "50"},
      {"address": "0xCCC...", "amount": "75"}
    ]
  }'

Refer to references/batch-payments.md for full contract ABI, CSV import format, supported chains, and error handling.

2. x402 Gateway (76+ Paid Endpoints)

The Spraay x402 gateway at gateway.spraay.app exposes 76+ endpoints across 16 categories. Agents pay per-request in USDC via the x402 protocol — no API keys, no subscriptions, just micropayments.

Categories and pricing:

When to use: Agent needs to call any paid API — AI inference, blockchain RPC, search, email, IPFS, or any infrastructure endpoint — and wants to pay per-call instead of managing API keys.

# Example: AI inference via x402
curl -X POST "$SPRAAY_GATEWAY_URL/api/ai/chat" \
  -H "Content-Type: application/json" \
  -H "X-402-Payment: <usdc-payment-header>" \
  -d '{"model": "claude-sonnet-4-20250514", "prompt": "Summarize this document"}'

Refer to references/x402-gateway.md for the full endpoint catalog, payment header format, and Bazaar discovery integration.

3. Bitcoin Batch Payments (PSBT)

Non-custodial Bitcoin batch payments using Partially Signed Bitcoin Transactions (PSBTs). Built on bitcoinjs-lib with Mempool.space API for fee estimation and broadcast.

Endpoints: batch-prepare ($0.02), batch-broadcast ($0.01), fee-estimate, utxos, balance, validate ($0.001 each)

When to use: User wants to send BTC to multiple recipients in a single transaction, or needs Bitcoin fee estimation and UTXO management.

# Prepare a Bitcoin batch transaction
curl -X POST "$SPRAAY_GATEWAY_URL/api/bitcoin/batch-prepare" \
  -H "Content-Type: application/json" \
  -d '{
    "recipients": [
      {"address": "bc1q...", "amount": 50000},
      {"address": "bc1q...", "amount": 25000}
    ],
    "feeRate": 10,
    "changeAddress": "bc1q..."
  }'

Refer to references/bitcoin-psbt.md for PSBT workflow, UTXO selection, and fee strategies.

4. Robot Task Protocol (RTP)

Open standard for AI agents to discover, commission, and pay physical robots for real-world tasks via x402 USDC micropayments. Built for the DePIN + AI agent intersection.

Endpoints: discover ($0.01), commission ($0.05), status ($0.005), cancel ($0.01), complete ($0.01), capabilities ($0.005), register ($0.02), heartbeat ($0.005)

When to use: Agent needs to hire a physical robot for a task — delivery, inspection, manipulation, sensing — and pay for it programmatically.

# Discover available robots
curl "$SPRAAY_GATEWAY_URL/api/rtp/discover?capability=delivery&location=37.7749,-122.4194"

# Commission a task
curl -X POST "$SPRAAY_GATEWAY_URL/api/rtp/commission" \
  -H "Content-Type: application/json" \
  -d '{
    "robotId": "robot-001",
    "task": "deliver_package",
    "params": {"destination": "123 Main St", "weight_kg": 2.5},
    "maxBudgetUSDC": "5.00"
  }'

Refer to references/rtp-protocol.md for the full RTP specification, device registration, and capability schemas.

5. Agent-to-Agent Payments

Spraay enables structured payments between autonomous agents — escrow, milestone-based releases, and batch settlement. Combined with x402, agents can transact without human intervention.

When to use: Multi-agent workflows where agents need to pay each other for completed tasks, hold funds in escrow, or settle batch payments between collaborators.

# Escrow: create a payment held until task completion
curl -X POST "$SPRAAY_GATEWAY_URL/api/escrow/create" \
  -H "Content-Type: application/json" \
  -d '{
    "payer": "0xAgent1...",
    "payee": "0xAgent2...",
    "amount": "10",
    "token": "USDC",
    "releaseCondition": "task_complete"
  }'

MCP Server

Spraay also has a published MCP server with 66 tools for deeper integration:

• Smithery: @plagtech/spraay-x402-mcp
• Official MCP Registry: io.github.plagtech/spraay-x402-mcp

Use the MCP server when you need programmatic access to all Spraay capabilities from an MCP-compatible agent (Claude, Cursor, etc.).

Supported Chains

Revenue Model

• Batch payments: 0.3% protocol fee per transaction
• Gateway endpoints: per-request x402 micropayments (prices above)
• All fees settle to 0xAd62f03C7514bb8c51f1eA70C2b75C37404695c8

Links

• Gateway: https://gateway.spraay.app
• Docs: https://docs.spraay.app
• GitHub: https://github.com/plagtech
• MCP: @plagtech/spraay-x402-mcp
• Twitter: @Spraay_app
• Farcaster: @plag