Quickstart¶

Get jquants-mcp answering Japanese stock questions in Claude in about 5 minutes.

Prerequisites¶

Python 3.10 or newer (python3 --version)
A J-Quants account with at least the Free plan (Light or above unlocks daily bars beyond the 12-week delay)
One of: Claude Code (CLI), Claude Desktop, or any MCP-aware client

1. Install jquants-mcp¶

uv (recommended)pipxpip

uv tool install jquants-mcp

pipx install jquants-mcp

pip install --user jquants-mcp

For inline candlestick / comparison charts, install with the [charts] extra:

uv tool install "jquants-mcp[charts]"

This pulls mplfinance and matplotlib (~60 MB). If you skip the extra, the chart tools are silently unregistered and the rest still works.

2. Get your J-Quants API key¶

The easiest way is the built-in browser login (PKCE flow):

jquants-mcp login

This opens the J-Quants OAuth page; after approving, the API key is saved to ~/.config/jquants-mcp/config.ini (mode 0600). Run jquants-mcp logout to clear it.

If you prefer to manage the key yourself, copy it from the J-Quants dashboard and put it in the same file:

# ~/.config/jquants-mcp/config.ini
[jquants]
api_key = YOUR_API_KEY_HERE

JQUANTS_API_KEY env var also works if you would rather not write a config file.

3. Connect to Claude¶

Claude Code (CLI)Claude Desktop

claude mcp add jquants -- jquants-mcp

Verify with claude mcp list. The next time you launch claude, the server is available.

Edit ~/Library/Application Support/Claude/claude_desktop_config.json (macOS) or the equivalent on Windows / Linux:

{
  "mcpServers": {
    "jquants": {
      "command": "jquants-mcp"
    }
  }
}

Restart Claude Desktop to pick up the change.

4. Try it out¶

Open Claude and ask:

今日の業種別騰落率を教えて

Claude calls get_sector_performance and returns a ranked sector table. The first call seeds the local cache; subsequent queries are instant.

Full TSE 17-sector ranking on the Claude iPhone app

Try a chart:

キオクシア（285A）のチャートを 3 か月分

If you installed the [charts] extra, Claude renders a candlestick PNG inline.

Candlestick chart for KIOXIA Holdings on the Claude iPhone app

Next steps¶

Tools → — what else you can ask Claude to do.
FAQ → — common errors, plan recommendations, multi-user mode.
Full reference: GitHub README covers config schema, deployment shapes (Docker / Cloud Run / self-hosted HTTP), per-tool parameter tables, and OAuth.