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Authentication

The Langfuse SDK uses HTTP Basic authentication with a public key and secret key pair. You can obtain these from your Langfuse project settings.

Basic Usage

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using Langfuse;

var client = new LangfuseClient(
    username: Environment.GetEnvironmentVariable("LANGFUSE_PUBLIC_KEY")!,
    password: Environment.GetEnvironmentVariable("LANGFUSE_SECRET_KEY")!);

Self-Hosted Instances

For self-hosted Langfuse instances, configure the base URL:

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var client = new LangfuseClient(
    username: Environment.GetEnvironmentVariable("LANGFUSE_PUBLIC_KEY")!,
    password: Environment.GetEnvironmentVariable("LANGFUSE_SECRET_KEY")!,
    baseUri: new Uri("https://your-langfuse-instance.example.com"));

Environment Variables

Variable Description
LANGFUSE_PUBLIC_KEY Your Langfuse project public key
LANGFUSE_SECRET_KEY Your Langfuse project secret key