> For clean Markdown of any page, append .md to the page URL.
> For a complete documentation index, see https://docs.ninjatrader.com/llms.txt.
> For AI client integration (Claude Code, Cursor, etc.), connect to the MCP server at https://docs.ninjatrader.com/_mcp/server.

# WebSocket API Reference

This is the complete reference for the Market Data WebSocket API — the channels you subscribe to and the messages the server streams back. It covers:

* **Quotes** — real-time top-of-book quotes.
* **Depth of Market (DOM)** — bid/ask price ladders and sizes.
* **Histograms** — volume-at-price data.
* **Charts** — historical and streaming bar data, including tick charts.

New here? Start with [Getting Started](/market-data/getting-started) to obtain access and
authorize the connection, then see [Real-Time Data via WebSocket](/market-data/websockets)
for the connection and subscription protocol.

Pick a channel in the sidebar to see its subscribe request and the message schema the server streams in response.