Template Instantiation

Template Instantiation

This skill creates .NET projects from templates using dotnet new CLI commands, with guidance for parameter validation, Central Package Management adaptation, and multi-project composition.

When to Use

• User asks to create a new .NET project, app, or service
• User needs a solution with multiple projects (API + tests + library)
• User wants to create a project that respects existing Directory.Packages.props
• User needs to install or manage template packages

When Not to Use

• User is searching for or comparing templates — route to template-discovery skill
• User wants to author a custom template — route to template-authoring skill
• User wants to add packages to an existing project — use dotnet add package directly

Inputs

Workflow

Step 1: Resolve template and parameters

If the user provides a natural-language description, map it to a template short name (see the keyword table in the template-discovery skill). If they provide a template name, proceed directly.

Use dotnet new <template> --help to review available parameters, defaults, and types for any parameters the user did not specify.

Step 2: Analyze the workspace

Check the existing solution structure before creating:

• Is Central Package Management (CPM) enabled? Look for Directory.Packages.props
• What target frameworks are in use? Check existing .csproj files
• Is there a global.json pinning the SDK?

This ensures the new project is consistent with the workspace.

Step 3: Preview the creation

Use dotnet new <template> --dry-run to show the user what files would be created. Confirm before proceeding.

dotnet new webapi --name MyApi --framework net10.0 --dry-run

Step 4: Create the project

Use dotnet new with the template name and all parameters:

dotnet new webapi --name MyApi --output ./src/MyApi --framework net10.0 --auth Individual

After creation, if the workspace uses CPM:

1. Check .csproj for inline <PackageReference> versions
2. Move version attributes to Directory.Packages.props as <PackageVersion> entries
3. Remove Version attributes from the .csproj

Step 5: Multi-project composition (optional)

For complex structures, create each project sequentially and wire them together:

dotnet new webapi --name MyApi --output ./src/MyApi
dotnet new xunit --name MyApi.Tests --output ./tests/MyApi.Tests
dotnet add ./tests/MyApi.Tests reference ./src/MyApi
dotnet sln add ./src/MyApi ./tests/MyApi.Tests

Step 6: Template package management

Install or uninstall template packages:

dotnet new install Microsoft.DotNet.Web.ProjectTemplates.10.0
dotnet new uninstall Microsoft.DotNet.Web.ProjectTemplates.10.0

Step 7: Post-creation verification

1. Verify the project builds: dotnet build
2. If added to a solution, verify dotnet build at the solution level
3. If CPM was adapted, verify Directory.Packages.props has the new entries

Validation

• Project was created successfully with the expected files
• Project builds cleanly with dotnet build
• If CPM is active, .csproj has no version attributes and Directory.Packages.props has matching entries
• Package versions in the project are current (not stale template defaults)
• If multi-project, all projects build and reference each other correctly

Common Pitfalls

More Info

• Central Package Management — CPM documentation
• dotnet new — CLI reference