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.NET SDK

ThirdwebApi .NET Integration

ThirdwebApi is the low-level HTTP client that powers the higher-level Thirdweb .NET SDK. Reach for it when you need to call https://api.thirdweb.com directly, build custom extensions, or inspect raw API payloads. The client works everywhere .NET runs, including Unity and MAUI.

What you unlock with ThirdwebApi

CapabilityWhy teams use it
AuthenticationOrchestrate SMS/email codes, SIWE, OAuth redirects, and passkeys from your own backend before handing off JWTs to wallets.
Wallet servicesLook up user/server wallets, enumerate tokens/NFTs, stream transaction history, sign messages, or send value programmatically.
Smart contractsBatch read/write invocations, fetch metadata & signatures, deploy bytecode, and capture emitted events with pagination.
Transactions pipelineQueue, monitor, and introspect Engine-backed transactions with execution metadata and status tracking.
Tokens & bridgeLaunch ERC20s, list circulating assets, price fiat ↔ crypto, or bridge/swap liquidity across chains.
Payments & x402Spin up hosted purchases, reconcile payment history, and prepare X402 machine-payable requests.
AI assistantEmbed natural-language orchestration that can read state, prepare contract calls, swap assets, or route transactions for end-users.

Backend first — All of the above accept your project secret via x-secret-key. Client-side use cases can opt into x-client-id + user JWT flows where supported.

When to reach for ThirdwebApi

  • You need endpoints that aren't yet wrapped by the higher-level SDK helpers.
  • You're building backend services that must authenticate with a Thirdweb secret key.
  • You want full visibility into contract metadata, ABI definitions, and compilation artifacts.
  • You plan to orchestrate auth, payments, or cross-chain flows without managing disparate providers.

Quickstart workflow

Instantiate an authenticated client

Create a reusable ThirdwebClient instance with your backend secret key. This unlocks every raw API surface exposed by Thirdweb.

// Program.cs / dependency container registration
var client = ThirdwebClient.Create(secretKey: Environment.GetEnvironmentVariable("THIRDWEB_SECRET_KEY"));

Example operation

Contract metadata is the canonical example for low-level reads. The same pattern applies to other namespaces like /v1/wallets/*, /v1/payments/*, or /ai/chat—swap the method call but keep your authenticated client.

// using Newtonsoft.Json;
 
var metadata = await client.Api.GetContractMetadataAsync(
	chainId: 1,
	address: "0xBd3531dA5CF5857e7CfAA92426877b022e612cf8"
);
 
Console.WriteLine($"ABI: {JsonConvert.SerializeObject(metadata.Result.Output.Abi, Formatting.Indented)}");
Console.WriteLine($"Compiler version: {metadata.Result.Compiler.Version}");