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.

Match the workspace, then stop. The highest-value move is aligning the new project with the repo it lands in: detect CPM (Directory.Packages.props) and the target framework used by neighbouring .csproj files, and mirror both. Treat the discovered target framework as an explicit choice — pass it as --framework so template-smart-defaults won't override it; deviate only when it's incompatible with a requested feature (then flag the conflict). Do this in as few steps as possible — a --dry-run, the create, and one dotnet build to confirm is usually enough. Extra exploratory turns add cost without improving the result.

Perform the requested creation. Do not return only a plan or statement of intent. Run state-dependent commands sequentially: inspect, dry-run, create, then build. Never launch create and build in parallel; a build-before-create race produces a false failure.

Do not predict the generated target framework. If the user and workspace do not supply one, inspect dotnet new <template> --help, choose a supported value (normally its documented default), pass it explicitly, then confirm the generated .csproj. Never announce an intermediate framework guess that was not grounded in the template's current choices.

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 templates — route to template-discovery skill; for a detailed side-by-side comparison — route to template-comparison 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.

When a parameter the user chose implies a value for an unset related parameter, invoke the template-smart-defaults skill to resolve the gap before assembling the command line — e.g., native AOT implies a recent AOT-capable target framework, a non-None --auth choice means HTTPS must stay enabled (don't add --no-https), and --use-controllers excludes the minimal-API option. Smart defaults only fill gaps; never let them override a value the user set explicitly. The workspace framework discovered in Step 2 counts as such an explicit value — pass it to smart-defaults as the chosen --framework so it isn't treated as an unset gap; deviate only if it is incompatible with the requested feature/template (then surface the conflict to the user).

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

Before running it, emit one compact decision line:

Creating <template> at <path>; framework=<value> (<user|workspace|template>); CPM=<on|off>.

This makes workspace adaptations explicit without adding a long report.