---
name: azure-functions-genai
description: >-
  Guides the design, implementation, and debugging of Azure Functions v4 (.NET 8/10 Isolated Worker)
  using the official Google.GenAI C# SDK for serverless AI endpoints.
---

# Azure Functions & Google.GenAI C# SDK Skill

Use this skill when developing, updating, or testing the C# serverless API endpoints located in `api/`.

---

## 1. Solution Architecture

The backend consists of an **Azure Functions v4 Isolated Worker** targeting **.NET 8.0**:
- Project file: `api/api.csproj`
- Runtime: `Microsoft.Azure.Functions.Worker` 2.50+ & `Google.GenAI` 1.20+
- Host configuration: `api/host.json`
- Application Insights integration: `Microsoft.ApplicationInsights.WorkerService`

---

## 2. Google.GenAI C# SDK Integration Patterns

### 2.1 Namespaces & Types
```csharp
using Google.GenAI;
using Google.GenAI.Types;
using Type = Google.GenAI.Types.Type; // Disambiguate with System.Type
```

### 2.2 Client Initialization
```csharp
var apiKey = System.Environment.GetEnvironmentVariable("GEMINI_API_KEY");
var client = new Client(apiKey: apiKey);
```

### 2.3 Structured Output Generation (JSON Schema)
```csharp
var schema = new Schema
{
    Type = Type.Object,
    Properties = new Dictionary<string, Schema>
    {
        { "distortionsIdentified", new Schema { Type = Type.Array, Items = new Schema { Type = Type.String } } },
        { "techniquesUsed", new Schema { Type = Type.Array, Items = new Schema { Type = Type.String } } },
        { "clinicalInsight", new Schema { Type = Type.String } },
        { "feedbackType", new Schema { Type = Type.String, Enum = new List<string> { "Constructive", "Positive", "Neutral" } } }
    },
    Required = new List<string> { "distortionsIdentified", "techniquesUsed", "clinicalInsight", "feedbackType" }
};

var response = await client.Models.GenerateContentAsync(
    model: "gemini-2.5-flash", 
    contents: promptContent,
    config: new GenerateContentConfig 
    {
        SystemInstruction = new Content { Parts = new List<Part> { new Part { Text = systemInstruction } } },
        ResponseMimeType = "application/json",
        ResponseSchema = schema
    });
```

---

## 3. Endpoints Matrix

| Route | HTTP Method | Function Name | Purpose |
|:---|:---|:---|:---|
| `/api/chat` | `POST` | `ChatProgression` | Headless roleplay progression with strict anti-meta guardrails |
| `/api/analysis` | `POST` | `ClinicalAnalysis` | Real-time clinical supervisor turn evaluation |
| `/api/scenario/generate` | `POST` | `GenerateScenario` | Dynamic CBT roleplay scenario generation |

---

## 4. Local Build & Test Verification
```bash
# Build the C# API project
dotnet build api/api.csproj

# Run local functions host (requires Azure Functions Core Tools)
func start --csharp --prefix api
```