# Stable Ripa

> Stable Ripa is an institutional-grade stablecoin banking and payment processing platform. It provides SUSD accounts, peer-to-peer transfers, a merchant REST payments API, and native AI agent integration via the Model Context Protocol (MCP).

Note: Stable Ripa is a developer demonstration platform. All transactions use simulated stablecoins (SUSD) in a sandboxed environment — no real-world assets are accepted or transacted.

## Platform Overview

Three integrated surfaces:

- **Customer Banking**: Stablecoin accounts with sub-second settlement, peer-to-peer transfers, and bill pay
- **Merchant Payments API**: REST API for charging, capturing, voiding, and refunding SUSD payments with HMAC-signed requests and webhook event delivery
- **MCP AI Agent Interface**: Streamable HTTP MCP server enabling AI agents to transact, query accounts, and manage webhooks autonomously

## Documentation

- [Quickstart Guide](https://stableripa.com/developer/quickstart): Get your first charge processed in under 5 minutes
- [Authentication](https://stableripa.com/developer/docs/authentication): API key setup and HMAC request signing (Stable-Signature header)
- [Charges](https://stableripa.com/developer/docs/charges): Creating, capturing, and managing payment charges
- [Refunds & Voids](https://stableripa.com/developer/docs/refunds): Processing refunds and voids against existing charges
- [Transactions](https://stableripa.com/developer/docs/transactions): Transaction lookup, history, and ledger queries
- [Webhooks](https://stableripa.com/developer/docs/webhooks): Real-time event notifications with HMAC signature verification
- [Error Reference](https://stableripa.com/developer/docs/errors): Error codes and response structures
- [MCP Integration](https://stableripa.com/developer/docs/mcp): Connecting AI agents via the Model Context Protocol

## Machine-Readable Specs

- [OpenAPI Specification](https://stableripa.com/openapi.json): Full machine-readable Payments API spec (OpenAPI 3.0)
- [Interactive API Explorer](https://stableripa.com/developer/api-reference): Swagger UI with live request execution
- [AI Plugin Manifest](https://stableripa.com/.well-known/ai-plugin.json): Plugin manifest for AI agent frameworks

## MCP Server (AI Agent Access)

Stable Ripa exposes a spec-compliant MCP server for autonomous AI agent integration:

- **Endpoint**: https://stableripa.com/mcp (Streamable HTTP, 2025-03-26 spec)
- **Auth**: OAuth 2.1 + PKCE (authorization code flow, S256 only)
- **Protected Resource Metadata**: https://stableripa.com/.well-known/oauth-protected-resource (RFC 9728)
- **Authorization Server Metadata**: https://stableripa.com/.well-known/oauth-authorization-server (RFC 8414)
- **Dynamic Client Registration**: https://stableripa.com/oauth/register (RFC 7591)

### MCP Tool Categories

- Account management: balance queries, account details, merchant info
- Transaction operations: history, filtering, ledger reads
- Payment actions: transfers, bill payments
- Webhook management: list, create, delete endpoints
- Admin tools: merchant statistics, platform oversight

## Company

- [About Stable Ripa](https://stableripa.com/about): Platform philosophy and the origin of the name
- [Developer Portal](https://stableripa.com/developer): Full developer documentation and API access
- [Terms of Use](https://stableripa.com/terms): Demo environment constraints and legal notices
- [Privacy Policy](https://stableripa.com/privacy): Data handling and privacy practices