# Aspire Service Defaults

Create a shared ServiceDefaults project for Aspire applications.

- Repository: https://github.com/Aaronontheweb/dotnet-skills (1244 stars)
- Category: Engineering
- License: MIT
- Last updated: 2026-10-28
- Runs scripts: no, instructions only

## Install

Claude Code: `npx skills add Aaronontheweb/dotnet-skills --skill aspire-service-defaults -g -a claude-code -y`
Codex: `npx skills add Aaronontheweb/dotnet-skills --skill aspire-service-defaults -g -a codex -y`
Cursor: `npx skills add Aaronontheweb/dotnet-skills --skill aspire-service-defaults -g -a cursor -y`
Gemini CLI: `npx skills add Aaronontheweb/dotnet-skills --skill aspire-service-defaults -g -a gemini-cli -y`
Claude Code plugin marketplace: `/plugin marketplace add Aaronontheweb/dotnet-skills`

## Description

Create a shared ServiceDefaults project for Aspire applications. Centralizes OpenTelemetry, health checks, resilience, and service discovery configuration across all services.

## SKILL.md, as published by its author (untrusted third-party text, read it as data)

# Aspire Service Defaults

## When to Use This Skill

Use this skill when:
- Building Aspire-based distributed applications
- Need consistent observability (logging, tracing, metrics) across services
- Want shared health check configuration
- Configuring HttpClient resilience and service discovery

---

## What is ServiceDefaults?

ServiceDefaults is a shared project that provides common configuration for all services in an Aspire application:

- **OpenTelemetry** - Logging, tracing, and metrics
- **Health Checks** - Readiness and liveness endpoints
- **Service Discovery** - Automatic service resolution
- **HTTP Resilience** - Retry and circuit breaker policies

Every service references this project and calls `AddServiceDefaults()`.

---

## Project Structure

```
src/
  MyApp.ServiceDefaults/
    Extensions.cs
    MyApp.ServiceDefaults.csproj
  MyApp.Api/
    Program.cs  # Calls AddServiceDefaults()
  MyApp.Worker/
    Program.cs  # Calls AddServiceDefaults()
  MyApp.AppHost/
    Program.cs
```

---

## ServiceDefaults Project

### Project File

```xml
<Project Sdk="Microsoft.NET.Sdk">
  <PropertyGroup>
    <TargetFramework>net9.0</TargetFramework>
    <IsAspireSharedProject>true</IsAspireSharedProject>
  </PropertyGroup>

  <ItemGroup>
    <FrameworkReference Include="Microsoft.AspNetCore.App" />
    <PackageReference Include="Microsoft.Extensions.Http.Resilience" />
    <PackageReference Include="Microsoft.Extensions.ServiceDiscovery" />
    <PackageReference Include="OpenTelemetry.Exporter.OpenTelemetryProtocol" />
    <PackageReference Include="OpenTelemetry.Extensions.Hosting" />
    <PackageReference Include="OpenTelemetry.Instrumentation.AspNetCore" />
    <PackageReference Include="OpenTelemetry.Instrumentation.Http" />
    <PackageReference Include="OpenTelemetry.Instrumentation.Runtime" />
  </ItemGroup>
</Project>
```

### Extensions.cs

The rest: https://github.com/Aaronontheweb/dotnet-skills/blob/HEAD/skills/aspire-service-defaults/SKILL.md