Oyster Ollama Chat

A pay-per-prompt AI chat application that monetizes an Ollama LLM behind the x402 payment protocol. Users connect a wallet, pay micro-amounts in USDC per request, and chat with the model. Responses are generated and signed inside an Oyster CVM TEE for end-to-end verifiability.

Architecture

┌────────────┐       ┌──────────────────┐       ┌──────────────┐
│  Frontend  │──────▶│  x402 Gateway    │──────▶│  Ollama      │
│  (Next.js) │ x402  │  (Rust / Axum)   │ HTTP  │  LLM Server  │
│  port 5000 │◀──────│  port 3000       │◀──────│  port 11434  │
└────────────┘       └──────────────────┘       └──────────────┘

1. The Frontend sends a chat request with an x402 payment header.
2. The x402 Gateway validates payment via the facilitator, forwards the request to Ollama, signs the response with a TEE-backed key, and returns it.
3. The Frontend renders the markdown response and displays signature verification info.

Quick Start

Backend (x402 Gateway)

The gateway is a high-performance Rust/Axum reverse proxy that intercepts HTTP requests, enforces x402 payment, and signs responses.

For full documentation, see marlinprotocol/x402-gateway.

Features

• Multi-Chain Support — Accept payments on Base, Polygon, Avalanche, Solana, and more.
• Per-Endpoint Pricing — Configure different USDC amounts for different routes.
• TEE Signatures — Responses signed with a secp256k1 key (via Oyster KMS).

Configuration

The gateway is configured via a config.json file.

Field	Description
gateway_port	Port the gateway listens on (default 3000)
facilitator_url	x402 facilitator service URL (e.g., https://www.x402.org/facilitator)
target_api_url	Backend API to proxy requests to (e.g., http://127.0.0.1:11434)
networks[].type	Type of blockchain network ("evm" or "solana")
networks[].network	Network ID (e.g., "base-sepolia", "solana-devnet")
networks[].payment_address	Wallet address for receiving payments (e.g., 0xd232A8b0F63a555d054134f67b298ffE955f3BAf for EVM or EGBQqKn968sVv5cQh5Cr72pSTHfxsuzq7o7asqYB5uEV for Solana)
protected_routes[].path	Protected API route (e.g., "/api/chat")
protected_routes[].usdc_amount	USDC amount required for accessing the route (e.g., 100)

Frontend

A Next.js 16 + React 19 chat interface with wallet integration and x402 payment handling.

cd x402-frotend
npm install
npm run dev

The frontend will start on http://localhost:5000. Open it in your browser, connect your wallet, and start chatting.

Scripts

Script	Description
npm run dev	Start dev server on port 5000
npm run build	Create optimised production build
npm start	Serve production build on port 5000

Deploy on Oyster CVM

Simulate locally:

oyster-cvm simulate --docker-compose docker-compose.yml \
  --init-params "config.json:1:0:file:./config.json" -p 3000

Deploy to production:

oyster-cvm deploy \
  --wallet-private-key <key> \
  --duration-in-minutes 30 \
  --arch amd64 \
  --docker-compose docker-compose.yml \
  --init-params "config.json:1:0:file:./config.json"

Verifying Signatures

Get the expected public key from Oyster KMS:

oyster-cvm kms-derive \
  --image-id <IMAGE_ID> \
  --path signing-server \
  --key-type secp256k1/public

If both public keys match, the response is verified as originating from the expected Oyster enclave running the correct image.

Supported Networks

EVM Mainnets: Base, Polygon, Avalanche, Sei, XDC, XRPL EVM, Peaq, IoTeX, Celo

EVM Testnets: Base Sepolia, Polygon Amoy, Avalanche Fuji, Sei Testnet, Celo Sepolia

Solana: Mainnet, Devnet