files-api

Files live under client.Beta.Files (namespace Anthropic.Models.Beta.Files).

Files API — C#

Files API (Beta)

Files live under client.Beta.Files (namespace Anthropic.Models.Beta.Files). BinaryContent implicit-converts from Stream and byte[].

using Anthropic.Models.Beta.Files;
using Anthropic.Models.Beta.Messages;

FileMetadata meta = await client.Beta.Files.Upload(
    new FileUploadParams { File = File.OpenRead("doc.pdf") });

// Referencing the uploaded file requires Beta message types:
new BetaRequestDocumentBlock {
    Source = new BetaFileDocumentSource { FileID = meta.ID },
}

The non-beta DocumentBlockParamSource union has no file-ID variant — file references need client.Beta.Messages.Create().

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