template-discovery

Template Discovery

This skill helps an agent find, inspect, and select the right dotnet new template for a given task using dotnet new CLI commands for search, listing, and parameter inspection.

When to Use

• User asks "What templates are available for X?"
• User describes a project in natural language ("I need a web API with authentication")
• User wants to compare templates or understand parameters before creating a project
• User needs to know what a template produces (files, structure) before committing

When Not to Use

• User wants to create a project — route to template-instantiation skill
• User wants to author or validate a custom template — route to template-authoring skill
• User wants a detailed side-by-side comparison of templates — route to template-comparison skill
• User wants smart cross-parameter defaults during creation — route to template-smart-defaults skill
• User is troubleshooting build issues — route to dotnet-msbuild plugin

Recommendation requests: answer first, confirm second. Inspection requests: inspect first. For a general "which template?" question, start from the Step 1 mappings so a transient CLI failure cannot leave the user without an answer. When the user explicitly asks what is installed, requests exact options/defaults, or asks for dry-run output, run the relevant dotnet new command before writing the final answer. Never end a turn on a dotnet new call or a "let me confirm..." teaser.

Inspection requests require inspection. If the user asks for installed choices, exact parameters/defaults, compatibility constraints, or the exact dry-run file list, run the corresponding dotnet new command. Do not replace observed data with remembered flags. Report a flag only when the current template's --help output contains it.

Inputs

Workflow

For recommendations, use Step 1 before Steps 2–4. For explicit inspection requests, execute the requested inspection first and use Step 1 only as a fallback.

Step 1: Resolve intent to template candidates

Map the user's natural-language description to template short names and parameters using these mappings.

Intent → template short name(s):

Keyword → parameter:

These are starting guesses. Always confirm the real parameter names/choices with dotnet new <template> --help, because parameter names vary by template (e.g., --auth vs --Authentication).

Some mapped short names are not present in a default SDK install — templates like maui, winui3, aspire-starter/aspire, func, and orleans typically require a workload (dotnet workload install <id>) and/or an additional template package (dotnet new install <package>). If a mapped short name does not appear in dotnet new list, fall back to dotnet new list/dotnet new search to find the right template and the package/workload that provides it before recommending it.

Resilience — always answer, even if the CLI fails. The intent mapping above is a usable answer on its own. Run dotnet new commands sequentially, one at a time — the template engine uses a global mutex, so firing several dotnet new <template> --help/--dry-run calls concurrently can produce a transient "mutex"/"persistence" error and empty output. If a command fails, retry it once; if it still fails, fall back to this intent/parameter mapping and give the user a concrete recommendation, noting that the exact parameter names/choices could not be CLI-confirmed. Never end the turn with no answer because a CLI call errored.

Step 2: Search for templates

Use dotnet new search to find templates by keyword across both locally installed templates and NuGet.org:

dotnet new search blazor

Use dotnet new list to show only installed templates, with optional filters:

dotnet new list --language C# --type project
dotnet new list web

If the user explicitly asks you to check both installed templates and NuGet.org, run and report both searches even when the SDK already includes a suitable template. Distinguish the built-in choice from installable alternatives:

• For an SDK-shipped template, say "no install needed — ships with the SDK" and do not invent

a package requirement.

• For each relevant NuGet result you recommend, copy the package ID from the actual search output

and give dotnet new install <package-id>.

• If the NuGet search returns no credible alternative, say so explicitly; the local match still

answers the request.

Step 3: Inspect template details

Use dotnet new <template> --help to get full parameter details for a specific template — parameter names, types, defaults, and allowed values:

dotnet new webapi --help

Copy the observed option names, choices, defaults, and compatibility notes into the answer. For example, Windows Service support is not universally a worker-template flag. If the installed worker --help does not expose one, say so and distinguish template creation from post-creation hosting configuration; never invent --windows or --use-windows-service.

Step 4: Preview output

Use dotnet new <template> --dry-run to show what files and directories a template would create without writing anything to disk:

dotnet new webapi --name MyApi --auth Individual --dry-run

If the dry-run fails (transient "mutex"/"persistence" error), retry once; if it still fails, give a representative structure (template family and typical file kinds) and note it isn't CLI-confirmed. Do not invent specific values, choices, or file paths. When the dry-run succeeds, preserve every actual path from its output. For a long list, render those paths as a directory tree rather than a flat wall of full paths; do not omit or invent entries. Follow the tree with a one-line purpose for each key entry point (for example Program.cs, App.razor, and the project file). A file list without those explanations is incomplete.

If command execution is unavailable, do not stop at "run this yourself." Give the representative tree and key-file explanations from the known template family, clearly labeled as unconfirmed, so the user still receives a useful preview.

If the user says not to create files, every copy-pasteable creation command must include --dry-run. A plain dotnet new ... command contradicts that request even when you did not execute it yourself.

Step 5: Present findings

Lead with the answer as a ready-to-run command, then justify it. Required shape:

Use `<template>` — one-line why. ``bash dotnet new <template> --name <Name> [--key params]

Then add supporting detail:

• Key parameters and recommended values (with the choices, e.g. --auth: None | Individual | SingleOrg | Windows)
• What to expect (files created, project structure)
• Any prerequisites — name the exact package to install (dotnet new install <id>), or say "no install needed — ships with the SDK" for a built-in template

An answer without a concrete, copy-pasteable command is what makes this skill tie with a plain reply — always give the command to run next.

Validation

• [ ] At least one template match was found for the user's intent
• [ ] Template parameters are explained with types and defaults
• [ ] User understands what the template produces before proceeding to creation
• [ ] Exact-option claims came from this template's observed --help output
• [ ] Advice-only commands that must not create files include --dry-run

Common Pitfalls

More Info

• dotnet new templates — built-in template reference
• Template Engine Wiki — template engine internals