# Superbridge Documentation > Complete documentation for the Superbridge cross-chain bridging API, SDK, and Widget. ## Quick Reference - Base URL: `https://api.superbridge.app` - Auth: `x-api-key` header on every request - OpenAPI spec: https://docs.superbridge.app/openapi.yaml - Full docs: https://docs.superbridge.app - Full documentation for LLMs: https://docs.superbridge.app/llms-full.txt ## Overview - [What is Superbridge?](https://docs.superbridge.app/overview): A cross-chain swapping and bridging platform that lets users move assets between blockchain networks - [Chains](https://docs.superbridge.app/overview/chains): Learn how Superbridge offers a production-ready onboarding experience for agents, developers, and users - [Rollups](https://docs.superbridge.app/overview/rollups): Learn how Superbridge offers a production-ready onboarding experience for agents, developers, and users - [Tokens](https://docs.superbridge.app/overview/tokens): A production-ready bridging experience for token issuers - [Interoperability Protocols](https://docs.superbridge.app/overview/interoperability-protocols): A production-ready bridging experience powered by your infrastructure - [Centralised Exchanges](https://docs.superbridge.app/overview/centralised-exchanges): A battle-tested, fee-free API for rebalancing funds across chains - [Solvers](https://docs.superbridge.app/overview/solvers): A battle-tested, fee-free API for moving funds across chains - [Ecosystems](https://docs.superbridge.app/overview/ecosystems): A production-ready bridging experience for your network of chains - [Agents & LLMs](https://docs.superbridge.app/overview/agents-llms): Programmatic cross-chain bridging for AI agents and automated systems - [Onboarding](https://docs.superbridge.app/overview/onboarding): Help users get started on new chains with a frictionless experience - [Bridging](https://docs.superbridge.app/overview/bridging): Move tokens between chains seamlessly - [Swapping](https://docs.superbridge.app/overview/swapping): Swap tokens across chains without needing to bridge first - [Compliance](https://docs.superbridge.app/overview/compliance): Industry-leading wallet screening and compliance standards ## API Reference - [Introduction](https://docs.superbridge.app/api-reference): Programmatic access to cross-chain bridging routes, tokens, chains, and transaction activity - [Authentication](https://docs.superbridge.app/api-reference/authentication): Authenticate your API requests with an API key - [OpenAPI Spec](https://docs.superbridge.app/api-reference/openapi): Machine-readable API specification following OpenAPI 3.0 - [Agents & LLMs](https://docs.superbridge.app/api-reference/agents-llms): Full documentation available as a single markdown file for LLMs and AI agents - [Chains](https://docs.superbridge.app/api-reference/chains): Retrieve the list of supported chains - [Tokens](https://docs.superbridge.app/api-reference/tokens): Retrieve the list of supported tokens - [Routes](https://docs.superbridge.app/api-reference/routes): Get available bridging routes for a token transfer between chains - [Activity](https://docs.superbridge.app/api-reference/activity): Retrieve bridging transaction activity for a given address - [Step Transaction](https://docs.superbridge.app/api-reference/step-transaction): Get the transaction data required to execute a specific step of a bridge transaction - [Index Transaction](https://docs.superbridge.app/api-reference/index-transaction): Notify the indexer about a submitted transaction - [Chain Identifiers](https://docs.superbridge.app/api-reference/chain-identifiers): How chains are identified in the Superbridge API - [Transaction Lifecycle](https://docs.superbridge.app/api-reference/transaction-lifecycle): How cross-chain transactions progress through multiple steps - [Routes vs. Quotes](https://docs.superbridge.app/api-reference/routes-vs-quotes): Understanding the difference between routes and quotes - [Route Errors](https://docs.superbridge.app/api-reference/route-errors): How to handle errors returned by individual route providers - [Approvals](https://docs.superbridge.app/api-reference/approvals): Handle token approval transactions before bridging - [Signing](https://docs.superbridge.app/api-reference/signing): Sign and submit pre-built transaction objects on-chain - [Indexing](https://docs.superbridge.app/api-reference/indexing): Ensure submitted transactions are tracked by the Superbridge Indexer - [Troubleshooting](https://docs.superbridge.app/api-reference/troubleshooting): Common issues and delays you may encounter - [Examples](https://docs.superbridge.app/api-reference/examples): End-to-end examples of common bridging flows - [Types](https://docs.superbridge.app/api-reference/types): All types returned by the Superbridge API ## SDK - [Introduction](https://docs.superbridge.app/sdk): A type-safe TypeScript wrapper around the Superbridge API - [Examples](https://docs.superbridge.app/sdk/examples): End-to-end examples of common bridging flows using the SDK - [Type Guards](https://docs.superbridge.app/sdk/type-guards): Type guard helpers for working with discriminated unions ## Widget - [Introduction](https://docs.superbridge.app/widget): A drop-in React component that adds cross-chain bridging to your application