FastFlowLM VS Code

Interact with and manage a FastFlowLM server from Visual Studio Code.

Features

• Chat with a FastFlowLM server through a webview panel.
• Register FastFlowLM as a native VS Code Chat language model provider.
• Discover available models through the OpenAI-compatible /models endpoint.
• Check connectivity and manage a local FastFlowLM server from the Command Palette.
• Follow server output and model activity in the FastFlowLM output channel.
• Configure the server URL, model, API key, command, arguments, and working directory.

Configuration

Open Settings and search for FastFlowLM:

• flm-vscode.serverUrl: API base URL. Defaults to http://127.0.0.1:8000/v1.
• flm-vscode.model: Initial model identifier. Defaults to qwen3.5:2b.
• flm-vscode.apiKey: Optional API key sent as a bearer token.
• flm-vscode.serverCommand: Optional local server command, such as python.
• flm-vscode.serverArgs: Arguments passed to the local server command.
• flm-vscode.serverCwd: Optional working directory for the server process.

For example, a local Python server can be managed with:

{
	"flm-vscode.serverCommand": "python",
	"flm-vscode.serverArgs": ["-m", "fastflowlm.server"],
	"flm-vscode.serverCwd": "C:/path/to/FastFlowLM"
}

Usage

1. Start a FastFlowLM server, or configure flm-vscode.serverCommand and use FastFlowLM: Start Server.
2. Use FastFlowLM: Check Server from the Command Palette to test connectivity.
3. Select a FastFlowLM model in the VS Code Chat model picker.

Use FastFlowLM: Show Activity Log to open the activity channel. It reports server startup and shutdown, server stdout/stderr, model discovery, request dispatch, response progress, and completion. This makes model loading and task progress visible even when the server is running as a child process.

The extension does not assume how FastFlowLM is installed or launched. Configure the command that matches your server installation. Native Chat requests use streaming responses when the server supports OpenAI-compatible SSE streaming.

Requirements

• VS Code 1.137.0 or newer.
• A FastFlowLM server exposing an OpenAI-compatible /v1 API.
• The configured model must support chat completions. Tool calling requires server support for OpenAI-compatible function tools.

Data and security

Chat messages, tool schemas, and tool results are sent to the configured FastFlowLM server. This extension does not send requests to a hosted service of its own. API keys are sent as bearer tokens and should be configured in user settings rather than committed to workspace settings.

The extension starts the configured server command with the current user permissions. Only configure commands and working directories you trust.

Troubleshooting

• Cannot reach server: verify flm-vscode.serverUrl, then run FastFlowLM: Check Server.
• Model not found: refresh models in the FastFlowLM chat panel and make sure flm-vscode.model matches the server's /models response.
• Context or token limit errors: reduce conversation history or increase the server KV capacity. Requests reserve up to 24,576 input tokens and 4,096 output tokens.

Known limitations

Token counting uses a conservative character-based estimate because the extension does not have access to each model's tokenizer. The server remains authoritative for its actual context window.

Development

npm install
npm run compile
npm test

Press F5 in VS Code to launch an Extension Development Host.

Current Scope

The extension manages one local server process. FastFlowLM receives VS Code tool schemas and conversation context, then returns text or tool calls through the native Chat provider API. The server must support OpenAI-compatible chat completions and function/tool calling.

NOTE

This is a work-in-progress, there's a number of things I want to implement - like te FLM server being a bit more chatty in the terminal - I want to see the status and the thinking process , not just a single word