template-smart-defaults

Development

Applies cross-parameter default rules when creating .NET projects with dotnet new, filling gaps consistently without overriding values the user set explicitly. USE FOR: choosing sensible defaults for related parameters during project creation, resolving cross-parameter interactions (AOT implies a compatible framework, auth implies HTTPS, controllers excludes minimal-API flags), explaining why a default was applied. DO NOT USE FOR: creating the project itself (use template-instantiation), finding or comparing templates (use template-discovery and template-comparison), authoring or validating custom templates (use template-authoring and template-validation).

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Template Smart Defaults

This skill helps an agent fill in cross-parameter defaults when creating a dotnet new project. The rules below are guidance heuristics that keep related parameters consistent — they only fill gaps and never override a value the user set explicitly.

When to Use

The user asks to create a project but leaves related parameters unspecified
A parameter the user chose implies a sensible value for another parameter
You need to explain why a particular default was selected

When Not to Use

User wants to actually create the project — route to template-instantiation
User wants to find or compare templates — route to template-discovery or template-comparison
User wants to author or validate a custom template — route to template-authoring or template-validation

Inputs

Input	Required	Description
Template short name	Yes	The template the project will be created from (e.g., `webapi`)
Parameters already chosen	Yes	The parameter values the user has explicitly set
Available choices	Recommended	Parameter names/choices from `dotnet new <template> --help`

Workflow

Gather the parameters the user has explicitly set.
Apply each rule below only where the corresponding parameter is unset — never override an explicit user value.
Log every applied default with a short rationale so the user can see and override it.
Confirm the chosen parameter names and choices against dotnet new <template> --help before creating.

AOT at create time vs publish time. --aot is a dotnet new flag only on the templates that expose it (e.g. console, worker, grpc); it is not on webapi/webapp. There is no --publish-aot template flag — publish-time native AOT is enabled with the MSBuild property PublishAot=true (via dotnet publish or in the .csproj), not through dotnet new. Apply the framework rule only when the template actually offers --aot.

Rules

Rule	Default applied	Rationale
`--aot` is set (on templates that support it, e.g. `console`/`worker`/`grpc`) and `--framework` is unset	Set `--framework` to the latest AOT-compatible framework the template offers	Native AOT requires a recent, AOT-capable target framework; using the latest avoids build failures.
`--auth` is anything other than `None`	Do NOT pass `--no-https`	Authentication flows (cookies, tokens, redirects) require HTTPS; disabling it breaks auth.
`--use-controllers` is set	Do NOT also pass a minimal-API flag	Controllers and minimal APIs are mutually exclusive program models; passing both is contradictory.
User set a value explicitly	Leave it unchanged	Smart defaults only fill gaps; explicit user intent always wins.

Validation

Each applied default was logged and explained to the user
No parameter the user set explicitly was overridden
Only unset parameters were filled
The resulting parameter names/choices were confirmed against dotnet new <template> --help

Common Pitfalls

Pitfall	Solution
Treating heuristics as enforcement	These are guidance rules, not validation. Always confirm against `dotnet new <template> --help` choices, since parameter names vary by template.
Overriding an explicit user value	Apply a rule only when the target parameter is unset.
Assuming a flag name	The exact flag differs per template (`--aot` exists on `console`/`worker`/`grpc` but not `webapi`; controllers use `--use-controllers`) — verify with `--help`.
Picking a framework the template doesn't support	Use the latest framework that appears in the template's `--framework` choices, not an arbitrary newest version.

More Info

dotnet new — CLI reference
Native AOT deployment — AOT framework requirements