Template smart defaults

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

1. Gather the parameters the user has explicitly set.
2. Apply each rule below only where the corresponding parameter is unset — never override a value the user set explicitly.
3. Confirm the chosen parameter names and choices against dotnet new <template> --help at creation time. For an advice-only request (the user isn't creating yet — e.g. "tell me the parameters/command"), answer from the rules below and note you'd confirm the exact names at creation; don't spend a --help call just to advise on well-known parameters.
4. Emit the two required outputs (see below) — this is what makes the skill decisive rather than inert.

Required output

Always produce both, in this order:

A. A "Defaults applied" log — one row per parameter, covering both the explicit values you preserved (Source = user) and the gaps you filled by rule (Source = rule), so the user can see and override every choice:

Parameter	Value	Source	Why
--framework	net10.0	rule	Native AOT (from --aot) needs the latest AOT-capable TFM
--auth	Individual	user	Explicitly requested — left unchanged

Use Source = user for explicit values (never overridden) and Source = rule for gap-fills.

B. The exact single dotnet new command line you would run — include only the flags you are actually passing. Do not list flags you decided not to pass (e.g. don't mention --no-https when you are keeping HTTPS; don't mention a minimal-API flag when using controllers). Silence on an omitted flag is the correct, decisive signal.

AOT at create time vs publish time. --aot is a dotnet new flag only on the templates that expose it — always confirm with dotnet new <template> --help rather than assuming a given template does or doesn't offer it. 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 any template whose --help exposes it) 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. (A framework already pinned by the workspace or global.json counts as set — keep it unless it's incompatible with AOT.)
--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

• A "Defaults applied" log was produced with a Source (user/rule) and rationale per row
• The exact single dotnet new command line was emitted, listing only flags actually passed
• No parameter the user set explicitly was overridden
• Only unset parameters were filled
• Parameter names/choices were confirmed against dotnet new <template> --help at creation (for advice-only requests, flagged as to-confirm rather than run eagerly)

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 — always verify with --help (e.g. --aot is present only where --help lists it; controllers use --use-controllers).
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