目前对最小API的Open API文档的支持非常少，并且据我所知不允许添加描述/摘要。计划为.NET 7添加描述的功能。不久Swashbuckle也应该consider EndpointMetadata for annotations。
issue相关

统一采购司

使用Swashbuckle nuget包和Swashbuckle.AspNetCore.Annotations的最新更新，您可以为端点添加描述：

builder.Services.AddSwaggerGen(opts => opts.EnableAnnotations());

app.MapGet("/weatherforecast", () =>
{
    // Implementation
})
.WithMetadata(new SwaggerOperationAttribute(summary: "Summary", description: "Descritption Test"));

// Or

app.MapGet("/weatherforecast1", [SwaggerOperation(summary: "Summary1", description: "Descritption Test1")] () =>
{
    // Implementation
});

更新2

对于.NET 7和最新的Swashbuckle.AspNetCore包，也可以使用WithDescription方法：

builder.Services.AddSwaggerGen();
...

app.MapGet("/weatherforecast", () =>
{
    // implementation
})
.WithDescription("Some Method Description")
.WithOpenApi();

EndpointDescriptionAttribute：

app.MapGet("/weatherforecast1", [EndpointDescription("Some Attribute description")] () =>
{
    // implementation
})
.WithOpenApi();

Package Swashbuckle.AspNetCore.Annotations6.3

...
builder.Services.AddSwaggerGen(c => c.EnableAnnotations());

var app = builder.build();

app.MapGet("/clients",
    [SwaggerOperation(
        Summary = "returns clients",
        Description = "more description on get `clients`")]
    [SwaggerResponse(200, "success")]
    [SwaggerResponse(500, "some failure")]
    async (IClientRepository repo) =>
    {
        var results = await repo.GetClientsAsync();
        return mapper.Map<IEnumerable<ClientModel>>(results);
    }).WithTags("Clients");

更多示例请访问https://github.com/domaindrivendev/Swashbuckle.AspNetCore#enrich-operation-metadata

1.安装软件包

dotnet add package Swashbuckle.AspNetCore.Annotations

2.编写代码

// Program.cs

builder.Services.AddSwaggerGen(x =>
{
  x.EnableAnnotations();
});

// app.MapGet("/hi", [SwaggerOperation(Summary = "summary001", Description = "description001 `adads`")] () => "Hi");

app.MapGet("/hi", () => "Hi")
  .WithMetadata(new SwaggerOperationAttribute("summary001", "description001"));

结果编号

你可以使用this guide。我使用Swashbuckle就可以了。有一些扩展方法附带了最小的API。下面是它的外观：

app.MapGet(“/books”, async (BooksDB db) =>
await db.Books.ToListAsync()
)
.Produces<List<Book>>(StatusCodes.Status200OK)
.WithName(“GetAllBooks”).WithTags(“Getters”);

你可以使用扩展方法，我认为这是一种更清晰的方式来记录API端点。2这样你就可以为每个端点定义通用的响应方法。
为此，您需要安装以下软件包：
Swashbuckle.AspNetCore和Swashbuckle.AspNetCore.Annotations

using Microsoft.AspNetCore.Authorization;
using Swashbuckle.AspNetCore.Annotations;

public static class MinimalAttributeExtensions
{
    public static RouteHandlerBuilder AllowAnonymous(this RouteHandlerBuilder endpoint)
    {
        endpoint.WithMetadata(new AllowAnonymousAttribute());
        return endpoint;
    }
    public static RouteHandlerBuilder Authorize(this RouteHandlerBuilder endpoint, string policy = null, string[] roles = null, params string[] schemes)
    {
        var authorizeAttribute = new AuthorizeAttribute();

        if (!string.IsNullOrEmpty(policy))
        {
            authorizeAttribute.Policy = policy;
        }

        if (roles != null && roles.Any())
        {
            authorizeAttribute.Roles = string.Join(',', roles);
        }

        if (schemes != null && schemes.Any())
        {
            authorizeAttribute.AuthenticationSchemes = string.Join(',', schemes);
        }

        endpoint.WithMetadata(authorizeAttribute);

        return endpoint;
    }
    public static RouteHandlerBuilder AddMetaData<T>(this RouteHandlerBuilder endpoint, string tag, string summary = null, string description = null)
    {
        endpoint.WithTags(tag);

        endpoint.WithMetadata(new SwaggerOperationAttribute(summary, description));

        endpoint.WithMetadata(new SwaggerResponseAttribute(200, type: typeof(T)))
                .WithMetadata(new SwaggerResponseAttribute(500, type: typeof(ErrorResponseModel)))
                .WithMetadata(new SwaggerResponseAttribute(400, type: typeof(ErrorResponseModel)))
                .WithMetadata(new SwaggerResponseAttribute(404, type: typeof(ErrorResponseModel)))
                .WithMetadata(new SwaggerResponseAttribute(422, type: typeof(ErrorResponseModel)))
                .WithMetadata(new SwaggerResponseAttribute(304, type: typeof(ErrorResponseModel)));

        return endpoint;
    }
    public static RouteHandlerBuilder AddMetaData(this RouteHandlerBuilder endpoint, string tag, string summary = null, string description = null)
    {
        endpoint.WithTags(tag);

        endpoint.WithMetadata(new SwaggerOperationAttribute(summary, description));

        endpoint.WithMetadata(new SwaggerResponseAttribute(500, type: typeof(ErrorResponseModel)))
                .WithMetadata(new SwaggerResponseAttribute(400, type: typeof(ErrorResponseModel)))
                .WithMetadata(new SwaggerResponseAttribute(404, type: typeof(ErrorResponseModel)))
                .WithMetadata(new SwaggerResponseAttribute(422, type: typeof(ErrorResponseModel)))
                .WithMetadata(new SwaggerResponseAttribute(304, type: typeof(ErrorResponseModel)));

        return endpoint;
    }
}

以下是如何使用这些扩展方法的示例：

app.MapGet(“/books”, async (BooksDB db) =>
{
    return await db.Books.ToListAsync()
})
.Authorize(policy : "AdminOnly", roles : new string[] {1,2}, schemes: "Bearer")
.AddMetaData<List<Book>>
(
    tag : "Books",
    summary : "Get All Books",
    description : "Get All Books in List, Roles Allowed => Admin Only"
);

这里的.AddMetaData<T>表示成功的响应模型，这也将添加到此端点的响应文档。在本例中，它是List<Book>。