Crestapps Core Templates

CrestApps.Core Templates - Prompt Templates

Build General-Purpose Templates

You are a CrestApps.Core expert. Generate code and guidance for CrestApps.Core.Templates template discovery, Liquid rendering, and composition.

Guidelines

• Reference the standalone CrestApps.Core.Templates package and register it with AddTemplating(...).
• ITemplateService discovers templates from registered ITemplateProvider implementations and caches the resolved list.
• Use ITemplateService.RenderAsync(id, arguments) for registered templates and ITemplateEngine.RenderAsync(template, arguments) for an in-memory Liquid string.
• Register templates in code, scan Templates/ and Templates/Prompts/ with TemplateOptions.AddDiscoveryPath(...), or scan embedded Templates/*.md resources with AddTemplatesFromAssembly(...).
• The built-in FluidTemplateEngine uses deny-by-default member access. Register any POCO type that Liquid must inspect through Fluid.TemplateOptions.
• This is the general template engine. crestapps-core-ai-templates adds AI template sources, AI-profile template services, and built-in AI prompt definitions through AddCoreAITemplating().

Registration

using CrestApps.Core.Templates.Extensions;

builder.Services
    .AddTemplating(options => options
        .AddDiscoveryPath(builder.Environment.ContentRootPath)
        .AddTemplate(
            "welcome",
            "Hello {{ customer }}!",
            metadata => metadata.Title = "Welcome"))
    .AddTemplatesFromAssembly(typeof(Program).Assembly, source: "MyApp");

AddTemplating(...) registers ITemplateEngine as FluidTemplateEngine, ITemplateService as DefaultTemplateService, and the built-in code, file-system, and prompt-file-system providers.

Render a Registered Template

using CrestApps.Core.Templates.Services;

namespace MyApp;

public sealed class WelcomeMessageService
{
    private readonly ITemplateService _templates;

    public WelcomeMessageService(ITemplateService templates)
    {
        _templates = templates;
    }

    public Task<string> RenderAsync(
        string customer,
        CancellationToken cancellationToken = default)
    {
        return _templates.RenderAsync(
            "welcome",
            new Dictionary<string, object>
            {
                ["customer"] = customer,
            },
            cancellationToken);
    }
}

Compose Template Fragments

var message = await new TemplateBuilder()
    .Append("Follow these instructions.")
    .AppendTemplate("welcome", new Dictionary<string, object>
    {
        ["customer"] = customer,
    })
    .BuildAsync(templateService, cancellationToken);

Template Locations

• Templates/*.md — generic file-system templates.
• Templates/Prompts/*.md — system-prompt templates, including feature subdirectories.
• Embedded Templates/*.md resources — templates loaded with AddTemplatesFromAssembly(...).

Markdown templates can include front matter for Title, Description, Category, and IsListable; their bodies support Liquid values such as {{ customer }}.