1# Azure Document Intelligence — .NET SDK Quick Reference
2 
3> Condensed from **azure-ai-document-intelligence-dotnet**. Full patterns (custom models, classifiers, layout extraction)
4> in the **azure-ai-document-intelligence-dotnet** plugin skill if installed.
5 
6## Install
7```bash
8dotnet add package Azure.AI.DocumentIntelligence
9```
10 
11## Quick Start
12```csharp
13using Azure.AI.DocumentIntelligence;
14var client = new DocumentIntelligenceClient(new Uri(endpoint), credential);
15var adminClient = new DocumentIntelligenceAdministrationClient(new Uri(endpoint), credential);
16```
17 
18## Non-Obvious Patterns
19- Analyze is async LRO: `await client.AnalyzeDocumentAsync(WaitUntil.Completed, "prebuilt-invoice", uri)`
20- Field access: `document.Fields.TryGetValue("VendorName", out DocumentField field)`
21- Custom model build: `BuildDocumentModelOptions(modelId, DocumentBuildMode.Template, blobSource)`
22- Entra ID requires custom subdomain, not regional endpoint
23 
24## Best Practices
251. Use DefaultAzureCredential for **local development only**. In production, use ManagedIdentityCredential — see [auth-best-practices.md](../auth-best-practices.md)
262. Reuse client instances — clients are thread-safe
273. Handle long-running operations with `WaitUntil.Completed`
284. Check field confidence — always verify `Confidence` property
295. Use appropriate model — prebuilt for common docs, custom for specialized
306. Use custom subdomain — required for Entra ID authentication
31