C# AI.Chat

ServiceStack.AI.Chat brings the llms.py interface to C# applications. The frontend is copied verbatim from llms-py; a C# backend integrates it with ServiceStack, ASP.NET Identity, OrmLite, and the host's App_Data directory. The migration includes Decision Studio, workspace browsing, Git, projects, Gemini RAG, profiles, skills, publishing, and subscription settings.

See the AI.Chat source and host guide for the implementation and integration requirements. Package/release availability should be checked there before choosing a deployment version.

Register the plugin

Register an OrmLite IDbConnectionFactory for chat storage and add the plugin before ServiceStack's startup loader runs:

services.AddPlugin(new ChatFeature());
services.AddServiceStack(typeof(MyServices).Assembly);

Provider keys come from the host's environment or configured variables. Browse to /chat.

services.AddPlugin(new ChatFeature {
    RoutePrefix = "/chat",
    RequireAuth = true,
    AuthType = ChatAuthType.OAuth,
    SignInUrl = "/Account/Login",
    EnableProviders = ["groq"],
    ToolsConfig = new() {
        EnableCodeExecution = false,
        EnableFilesystemTools = false,
        AllowedDirectories = [],
    },
});

Identity and storage

Identity Auth cookies supply the default sign-in flow and authenticated username used to partition storage. ChatAuthType.ApiKey uses ApiKeysFeature. The OpenAI-compatible chat-completions endpoint supports Identity cookies or bearer API keys when the corresponding host features are registered.

With RequireAuth = false, data belongs to the default user. File-backed configuration, cached media, projects, Jev recipes, and per-user grants live under App_Data/chat; threads, requests, and media use OrmLite. Back up the database and matching App_Data before upgrading.

Shared UI, explicit host capabilities

The frontend modules, styles, recipes, prompts, themes, and profiles are shared with llms-py. Backend capabilities still depend on the host: Identity replaces Python's application authentication, execution and filesystem tools are opt-in, and the Python browser extension is not ported. Anthropic uses an API key rather than borrowing a local Claude Code subscription.

Git's hosted transport rules differ from local llms-py, and subscription credential lifecycle behavior must be checked against the C# host guide. Identical UI does not imply identical deployment permissions.

Sharing Projects

share_static is enabled by default; share_llmspy is disabled by default. Static publishing requires no remote account. Its Folder tab appears for a selected project or a chat belonging to one. Enable remote publishing explicitly before registering the plugin:

var chat = new ChatFeature();
chat.ShareLlmspy.Enabled = true;
services.AddPlugin(chat);

Remove share_llmspy from any configured DisableExtensions or disable_extensions list as well. To disable static sharing entirely, set chat.ShareStatic.Enabled = false. With no available sharing tabs, the toolbar omits the Share icon.

The default export directory is <WebContentDirectory>/p/<user>/<project-folder>/, typically wwwroot/p/<user>/<project-folder>/. When BaseUrl is empty or null, links use the current browser origin and BasePath, for example https://example.com/p/alice/my-project/ when Chat is at /chat. The UI displays the destination as ~/alice/my-project; project links open in a new window.

Configure globally in App_Data/chat/user/default/share_static/config.json. The file is optional; omitting directory uses the host web content directory's p folder:

{
  "enabled": true,
  "basePath": "/p/",
  "baseUrl": ""
}

Or supply a typed code override:

var chat = new ChatFeature();
chat.ShareStatic.StaticPublish = new StaticPublishConfig {
    // Omit Directory to use the host web content directory's p folder.
    BasePath = "/p/",
    BaseUrl = "", // Use the current browser origin.
};
services.AddPlugin(chat);

The code override replaces the file configuration, with class defaults for omitted fields. An explicit relative Directory resolves from the host's working directory. Set BaseUrl to a public HTTP(S) URL including its mount path to use another domain; its path overrides BasePath. Restart after changing file configuration. Named-user settings do not override these host settings.

Serve default exports through the host's normal static-file middleware before routing, especially with a root-mounted Chat UI:

app.UseDefaultFiles();
app.UseStaticFiles();
app.UseRouting();
app.UseServiceStack(new AppHost(), options => options.MapEndpoints());

A custom export directory needs a corresponding static-file mapping or independent static server. See Publishing for build-directory selection, HTML preparation, status, and remote account setup. Remote grants use user/<user>/share_llmspy/config.json under App_Data.

Keep shared assets synchronized

From the ServiceStack.AI.Chat library checkout:

./sync.sh --dry-run
./sync.sh
./sync.sh --check

Full sync copies owned shared assets into the library's chat/ directory and records their hashes in chat/shared-assets.json. It preserves C# Identity/credentials UI, host customizations, deployed App_Data, and upstream files. A parity check is read-only. Syncing does not implement new backend APIs; build and run ServiceStack.AiTests after updating embedded assets.

See the source guide's sync contract for prerequisites and supported targeted sync options.