> ## Documentation Index
> Fetch the complete documentation index at: https://docs.nebulaonchain.xyz/llms.txt
> Use this file to discover all available pages before exploring further.

# Payment tools

> Swaps, x402, and MPP session tools.

# Payment tools

## Swaps

| Tool             | Params                             | Notes                         |
| ---------------- | ---------------------------------- | ----------------------------- |
| `get_swap_quote` | `from_asset`, `to_asset`, `amount` | DEX quote                     |
| `swap`           | same + optional `max_slippage_bps` | Default slippage 100 bps (1%) |

Assets are `XLM` or `USDC`. See [Swap guide](/guides/swap).

## x402

| Tool         | Params                            | Notes             |
| ------------ | --------------------------------- | ----------------- |
| `x402_fetch` | `url`, optional `max_amount_usdc` | Auto-pay HTTP 402 |
| `x402_pay`   | `url`, amount fields per schema   | Pay known price   |

## MPP

| Tool                | Params             | Notes                          |
| ------------------- | ------------------ | ------------------------------ |
| `mpp_open_session`  | budget + recipient | Opens channel                  |
| `mpp_fetch`         | URL                | Off-chain commit + fetch       |
| `mpp_status`        | —                  | Session snapshot               |
| `mpp_close_session` | —                  | Settle on-chain, refund unused |

Guides: [x402](/guides/x402-payments), [MPP](/guides/mpp-sessions).