> For the complete documentation index, see [llms.txt](https://docs.fast.xyz/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.fast.xyz/sdk-references.md).

# SDK References

- [Overview](https://docs.fast.xyz/sdk-references/overview.md)
- [Core SDK Execution](https://docs.fast.xyz/sdk-references/core-sdk-execution.md): The foundation layer for account-to-account operations
- [fast-sdk](https://docs.fast.xyz/sdk-references/core-sdk-execution/fast-sdk.md): Fast SDK (@fastxyz/sdk) — TypeScript SDK for building on the Fast payment network. Provides FastProvider, Signer, and TransactionBuilder for transactions, account queries, and token management.
- [allset-sdk](https://docs.fast.xyz/sdk-references/core-sdk-execution/allset-sdk.md): AllSet SDK (@fastxyz/allset-sdk) — TypeScript SDK for bridging tokens between Fast and EVM chains. Provides deposit (EVM → Fast), withdraw (Fast → EVM), and custom intent execution.
- [Payment Protocol Adapters](https://docs.fast.xyz/sdk-references/payment-protocol-adapters.md): Standardized protocols for entity-to-entity payment flows.
- [x402-sdk](https://docs.fast.xyz/sdk-references/payment-protocol-adapters/x402-sdk.md): TypeScript SDK for the x402 HTTP payment protocol — add crypto payments to any API.
- [x402-client](https://docs.fast.xyz/sdk-references/payment-protocol-adapters/x402-sdk/x402-client.md): x402 Client SDK (@fastxyz/x402-client) — pays for HTTP resources protected by the x402 payment protocol.
- [x402-server](https://docs.fast.xyz/sdk-references/payment-protocol-adapters/x402-sdk/x402-server.md): x402 Server SDK (@fastxyz/x402-server) — middleware for protecting HTTP resources with x402 payment requirements.
- [x402-facilitator](https://docs.fast.xyz/sdk-references/payment-protocol-adapters/x402-sdk/x402-facilitator.md): x402 Facilitator (@fastxyz/x402-facilitator) — verifies and settles x402 payments for supported Fast and EVM flows.
- [Funding Abstraction](https://docs.fast.xyz/sdk-references/funding-abstraction.md): On-ramps and off-ramps for getting money into and out of Fast.
- [Swapper On-ramp](https://docs.fast.xyz/sdk-references/funding-abstraction/swapper-on-ramp.md)


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