Documentation Index
Fetch the complete documentation index at: https://docs.x402.org/llms.txt
Use this file to discover all available pages before exploring further.
SDK Features
This page tracks which features are implemented in each SDK (TypeScript, Go, Python v2).
Core
| Component | TypeScript | Go | Python |
|---|
| Server | ✅ | ✅ | ✅ |
| Client | ✅ | ✅ | ✅ |
| Facilitator | ✅ | ✅ | ✅ |
HTTP Framework Integrations
| Role | TypeScript | Go | Python |
|---|
| Server | Express, Hono, Next.js, Fastify | Gin, net/http, Echo | FastAPI, Flask |
| Client | Fetch, Axios | net/http | httpx, requests |
Networks
| Network | TypeScript | Go | Python |
|---|
| evm (EIP-155) | ✅ | ✅ | ✅ |
| svm (Solana) | ✅ | ✅ | ✅ |
| avm (Algorand) | ✅ | ❌ | ❌ |
| stellar | ✅ | ❌ | ❌ |
| aptos | ✅ | ❌ | ❌ |
Mechanisms
| Mechanism | TypeScript | Go | Python |
|---|
| exact/evm (EIP-3009) | ✅ | ✅ | ✅ |
| exact/evm (Permit2) | ✅ | ✅ | ✅ |
| exact/svm (SPL) | ✅ | ✅ | ✅ |
| exact/avm (ASA) | ✅ | ❌ | ❌ |
| exact/stellar (Soroban) | ✅ | ❌ | ❌ |
| exact/aptos (Fungible Assets) | ✅ | ❌ | ❌ |
| upto/evm (Permit2) | ✅ | ✅ | ✅ |
Extensions
| Extension | TypeScript | Go | Python |
|---|
| bazaar (server) | ✅ | ✅ | ✅ |
| bazaar (facilitator client - list) | ✅ | ✅ | ✅ |
| bazaar (facilitator client - search) | ✅ | ✅ | ✅ |
| sign-in-with-x | ✅ | ❌ | ❌ |
| payment-identifier | ✅ | ✅ | ✅ |
| offer-receipt | ✅ | ❌ | ❌ |
| eip2612-gas-sponsoring | ✅ | ✅ | ✅ |
| erc20-approval-gas-sponsoring | ✅ | ✅ | ✅ |
Client Hooks
| Hook | TypeScript | Go | Python |
|---|
| onBeforePaymentCreation | ✅ | ✅ | ✅ |
| onAfterPaymentCreation | ✅ | ✅ | ✅ |
| onPaymentCreationFailure | ✅ | ✅ | ✅ |
| onPaymentRequired (HTTP) | ✅ | ❌ | ❌ |
Server Hooks
| Hook | TypeScript | Go | Python |
|---|
| onBeforeVerify | ✅ | ✅ | ✅ |
| onAfterVerify | ✅ | ✅ | ✅ |
| onVerifyFailure | ✅ | ✅ | ✅ |
| onBeforeSettle | ✅ | ✅ | ✅ |
| onAfterSettle | ✅ | ✅ | ✅ |
| onSettleFailure | ✅ | ✅ | ✅ |
| onProtectedRequest (HTTP) | ✅ | ✅ | ❌ |
Facilitator Hooks
| Hook | TypeScript | Go | Python |
|---|
| onBeforeVerify | ✅ | ✅ | ✅ |
| onAfterVerify | ✅ | ✅ | ✅ |
| onVerifyFailure | ✅ | ✅ | ✅ |
| onBeforeSettle | ✅ | ✅ | ✅ |
| onAfterSettle | ✅ | ✅ | ✅ |
| onSettleFailure | ✅ | ✅ | ✅ |
Extension Hooks
| Hook | TypeScript | Go | Python |
|---|
| enrichDeclaration | ✅ | ✅ | ✅ |
| enrichPaymentRequiredResponse | ✅ | ❌ | ❌ |
| enrichSettlementResponse | ✅ | ❌ | ❌ |
MCP (Model Context Protocol)
| Feature | TypeScript | Go | Python |
|---|
| MCP server payment wrapper | ✅ | ✅ | ✅ |
| MCP client (auto-pay tools) | ✅ | ✅ | ✅ |
| Bazaar discovery for MCP tools | ✅ | ✅ | ✅ |
HTTP Server Features
| Feature | TypeScript | Go | Python |
|---|
| dynamicPayTo | ✅ | ✅ | ✅ |
| dynamicPrice | ✅ | ✅ | ✅ |
| paywall (browser UI) | ✅ | ✅ | ✅ |