QueryMT for VS Code

AI coding agent powered by QueryMT, integrated directly into VS Code's chat panel.

For detailed documentation on the agent, including configuration and usage, see the QueryMT Agent Documentation.

Features

Chat Participant (@querymt)

Type @querymt in the VS Code chat panel to interact with the QueryMT agent. It can:

• Answer questions about your codebase
• Write and edit code across files
• Run shell commands
• Analyze build errors and fix them
• Use VS Code language intelligence (diagnostics, references, definitions, symbols)

Language Model Provider

QueryMT exposes its configured LLM providers (Anthropic, OpenAI, local llama.cpp, Ollama) in VS Code's model picker. Other extensions can use these models through the standard VS Code Language Model API.

Workspace Intelligence

The agent has access to VS Code's language server features:

• Diagnostics -- see errors and warnings from all language servers
• Go to Definition -- navigate to symbol definitions
• Find References -- find all usages of a symbol
• Document Symbols -- list all symbols in a file
• Workspace Symbols -- search symbols across the project
• Hover -- get type information and documentation
• Type Definition -- navigate to type definitions

Requirements

• VS Code 1.99.0 or later
• Network access on first run if qmtcode needs to be auto-downloaded

Setup

1. Install the extension
2. Open a workspace folder
3. The extension starts the agent automatically (configurable via querymt.autoStart)
4. If qmtcode is missing, the extension auto-downloads the correct binary for your platform
5. Type @querymt in the chat panel to begin

Manual Installation (optional)

If you prefer to manage binaries yourself, install qmt and qmtcode manually:

macOS / Linux:

curl -sSf https://query.mt/install.sh | sh

Nightly channel:

curl -sSf https://query.mt/install.sh | sh -s -- --nightly

Windows PowerShell:

irm https://query.mt/install.ps1 | iex

Windows nightly channel:

$env:QMT_CHANNEL='nightly'; irm https://query.mt/install.ps1 | iex

You can also set querymt.binaryPath to point to a specific binary.

Authentication

The extension supports two authentication methods: API keys (environment variables or config file) and OAuth (browser-based sign-in for supported providers).

API Key Setup

Set the appropriate environment variable for your provider before launching VS Code:

macOS / Linux:

export ANTHROPIC_API_KEY="sk-ant-..."
export OPENAI_API_KEY="sk-..."

Windows PowerShell:

$env:ANTHROPIC_API_KEY = "sk-ant-..."
$env:OPENAI_API_KEY = "sk-..."

You can also set keys in a TOML config file (see querymt.configFile setting):

[agent]
provider = "anthropic"
model = "claude-sonnet-4-20250514"
api_key = "${ANTHROPIC_API_KEY}"

Common provider environment variables:

Provider	Environment Variable
Anthropic	ANTHROPIC_API_KEY
OpenAI	OPENAI_API_KEY
Google Gemini	GEMINI_API_KEY
Mistral	MISTRAL_API_KEY
Codex	CODEX_API_KEY

OAuth Sign-In

The following providers support OAuth-based authentication directly from VS Code:

• Anthropic -- Claude models via Anthropic Max
• Google -- Gemini models
• Codex -- Codex models
• Kimi -- Kimi models (kimi-oauth)

To sign in:

1. Run QueryMT: Sign In to Provider from the command palette (or status bar menu)
2. Select a provider from the list
3. Your browser opens the authorization page
4. After authorizing, the extension detects completion automatically (redirect-based providers) or prompts you to paste a code (device-based providers)

Credentials are stored securely by the agent in the system keyring -- the extension never stores tokens itself.

To check status or sign out, use QueryMT: Show Auth Status or QueryMT: Sign Out of Provider.

Full Provider Reference

For the complete list of supported providers, authentication methods, and model configuration options, see the Available Providers documentation.

Auth Troubleshooting

"No auth-enabled providers found" The agent has no configured providers that support OAuth. Ensure your agent config includes at least one OAuth-capable provider (anthropic, google, kimi-oauth, codex). Restart the agent after changing configuration.

API key not recognized

• Verify the environment variable is set in the shell that launched VS Code (run echo $ANTHROPIC_API_KEY or equivalent).
• If using a TOML config file, check that querymt.configFile points to the correct path.
• VS Code may need to be restarted after setting environment variables.

OAuth token expired Run QueryMT: Sign In to Provider again. The agent will refresh or re-authenticate as needed.

Sign-in times out The extension polls for up to 2 minutes after opening the browser. If the authorization page takes longer, run QueryMT: Show Auth Status to check the current state, then retry sign-in.

Provider/model mismatch Ensure querymt.defaultProvider and querymt.defaultModel correspond to a valid combination. For example, anthropic with claude-sonnet-4-20250514, not openai with a Claude model.

Agent not connected All auth commands require a running agent. Check the status bar indicator, and run QueryMT: Restart Agent or QueryMT: Show Agent Logs to diagnose.

Extension Settings

Setting	Default	Description
querymt.binaryPath	""	Absolute path to qmtcode. If empty, extension auto-discovers and can auto-download.
querymt.defaultProvider	"anthropic"	Default LLM provider (anthropic, openai, llama_cpp, ollama)
querymt.defaultModel	"claude-sonnet-4-20250514"	Default model identifier
querymt.configFile	""	Path to a QueryMT agent TOML config file
querymt.autoStart	true	Automatically start the agent when a workspace is opened
querymt.maxRestarts	5	Maximum automatic restart attempts after agent crashes
querymt.autoDownload	true	Automatically download qmtcode when not found locally
querymt.channel	"stable"	Release channel for auto-download (stable or nightly)

Commands

• QueryMT: Restart Agent -- Restart the agent process
• QueryMT: Show Agent Logs -- Open the output channel with agent logs
• QueryMT: Manage Provider -- Configure provider settings
• QueryMT: Sign In to Provider -- Start OAuth sign-in for supported providers
• QueryMT: Sign Out of Provider -- Remove OAuth credentials
• QueryMT: Show Auth Status -- View authentication state for all providers
• QueryMT: Agent Status -- Quick actions from the status bar

Status Bar

The status bar shows the current agent connection state:

• $(check) QueryMT -- Connected and ready
• $(sync~spin) QueryMT -- Connecting...
• $(circle-slash) QueryMT -- Disconnected
• $(error) QueryMT -- Error (click for recovery options)

Click the status bar item for quick access to restart, logs, and settings.

Architecture

The extension communicates with the qmtcode binary over stdio using the Agent Client Protocol (ACP). The agent runs as a child process and exchanges JSON-RPC messages for session management, prompt processing, and tool execution.

Development

# Install dependencies
npm install

# Build
npm run build

# Watch mode
npm run watch

# Type check
npm run lint

# Package VSIX
npm run package