# Nightwatch

> Nightwatch 夜航社 is an options market structure terminal and research community for US equity options traders.

Nightwatch helps options traders see dealer positioning structure: GEX and Dealer GEX Chart intraday levels, the multi-expiry Dealer Heatmap with GEX and VEX (vanna exposure) views, the Ask APEX in-product AI structure assistant, a market-wide live options flow feed, dark pool large-print price levels on the chart, implied volatility term structure, 0DTE Replay Lab historical sessions, and AI-assisted market structure research — in one product experience. Dealer GEX, Dealer Heatmap GEX and VEX grids, Standard GEX history, dark pool data and the other datasets listed by `GET /v1/discover` are available programmatically through the Nightwatch Data API and a hosted MCP server; Ask APEX, Replay Lab and research reports are available in the product only.

Important context:
- Product brand: Nightwatch
- Community name / Chinese alias: 夜航社
- Primary audience: active options traders monitoring SPY, QQQ, IWM, VIX, Mag 7 equities, and 0DTE structure
- Coverage: 300+ US equity tickers, including major indices, ETFs and actively traded single names
- Language: the product interface and community are in Simplified Chinese; Ask APEX answers in Chinese, English or Traditional Chinese, following the language of the question
- Access model: Discord login identifies the user; subscription and access are handled through the product access flow
- This is market data and structure analysis, **not financial advice**

## When to use Nightwatch

Reach for Nightwatch when a task needs **dealer options positioning structure for US equities** — not generic quotes, news, or fundamentals. Good fits:

- "Where are the key levels for SPY today?" — Dealer GEX snapshot returns the ranked intraday levels with a structure summary.
- "How did dealer positioning shift through the session?" — Dealer GEX history returns the intraday time series.
- "Where is structure concentrated over the next few months?" — Dealer Heatmap returns dealer positioning across strike and expiry.
- "Where would dealer hedging concentrate if implied volatility moves?" — Dealer Heatmap VEX returns dealer vanna exposure across strike and expiry.
- "What is chain-level aggregate gamma exposure over time?" — Standard GEX history returns the aggregate series.
- Research and backtesting on historical 0DTE sessions — Replay Lab.

Not a fit: order execution, brokerage, portfolio accounting, real-time equity quotes as a general market data feed, or any request for a buy/sell recommendation.

How an agent should call us: authenticate with a Bearer Data API key (`Authorization: Bearer sk_live_...`), then either call the REST endpoints directly or connect to the hosted MCP server and use its tools. Start from `GET /v1/discover` to learn which datasets the key can reach and how much quota remains. Every response carries rate-limit and quota headers plus a `request_id`.

## Developer and agent surfaces

- [REST API base](https://api.yehangshe.com): Nightwatch Data API, Bearer API key auth
- [OpenAPI 3.1 spec](https://api.yehangshe.com/v1/openapi.json): machine-readable definition of every endpoint, no auth required
- [MCP server](https://mcp.yehangshe.com/mcp): hosted Model Context Protocol server, Streamable HTTP transport, POST only, Bearer Data API key
- [Developer documentation](https://docs.yehangshe.com): quickstart, authentication, endpoint reference
- [Quota and rate limits](https://docs.yehangshe.com/api/quota-and-rate-limits): monthly quota, rate limiting and zero-cost rules
- API keys are generated self-serve from the account page by subscribed users.

## Public Pages

- [Nightwatch homepage](https://yehangshe.com/): Product overview, Dealer GEX and Heatmap examples, Ask APEX and options flow, Replay/IV tools, pricing and FAQ. Also served as markdown via `Accept: text/markdown`, or at [/index.md](https://yehangshe.com/index.md)
- [About Nightwatch](https://yehangshe.com/about/): What the product is, who operates it, and what it does not do
- [Contact](https://yehangshe.com/contact/): Official email (nightwatch@yehangshe.com), Discord community, developer support
- [Pricing](https://yehangshe.com/pricing.md): Plan tiers, prices, features and cancellation terms in plain markdown
- [Nightwatch glossary](https://yehangshe.com/glossary/): Public market-structure definitions for AI agents and search users
- [Privacy policy](https://yehangshe.com/privacy/): How identity, subscription, usage and support data are handled
- [Terms of service](https://yehangshe.com/terms/): Website, subscription access, and market-structure tool usage rules

## Product Capabilities

These capabilities are summarized on the public homepage and become available through the logged-in Nightwatch product experience:
- GEX dashboard: Gamma exposure structure and heatmap views
- Dealer GEX Chart: 0DTE Dealer GEX Pulse levels overlaid on price charts, including a tri-view for monitoring three tickers at once and an optional dark pool large-print price level overlay
- Dealer Heatmap: Multi-expiry dealer positioning structure across strike and time, switchable between GEX and VEX (vanna exposure) views
- Ask APEX: In-product AI market structure assistant. Reads the live structure for any covered ticker, historical moments within 90 days and two-moment comparisons, and explains terminology with documentation links. It does not give buy/sell recommendations; a daily usage allowance applies
- Options Flow: Market-wide live feed of large options orders, with split fills merged into single orders and multi-leg strategies identified; filters with saved presets, per-contract drilldown, and contract lookup and favorites
- IV volatility analysis: Implied volatility and term structure analysis
- 0DTE Replay Lab: SPX 0DTE replay of trading days from the last 90 days, with real GEX snapshots and option price snapshots for replaying option-combination behavior
- Nightwatch Research: Discord-delivered, AI-assisted market structure research for reference and education only

Public glossary entries:
- [Gamma Exposure (GEX)](https://yehangshe.com/glossary/gex/)
- [Dealer GEX](https://yehangshe.com/glossary/dealer-gex/)
- [Dealer Heatmap](https://yehangshe.com/glossary/dealer-heatmap/)
- [Charm](https://yehangshe.com/glossary/charm/)
- [Vanna](https://yehangshe.com/glossary/vanna/)
- [Gamma Flip](https://yehangshe.com/glossary/gamma-flip/)
- [Vol Trigger](https://yehangshe.com/glossary/vol-trigger/)
- [Call Wall](https://yehangshe.com/glossary/call-wall/)
- [Put Wall](https://yehangshe.com/glossary/put-wall/)
- [0DTE](https://yehangshe.com/glossary/0dte/)
- [IV Rank](https://yehangshe.com/glossary/iv-rank/)

Status page note:
- https://yehangshe.com/status is a public operational status page, but it is intentionally excluded from the sitemap and marked noindex by the server response header.

## Official accounts

- [Nightwatch on X](https://x.com/Nightwatch_AI): Free weekly US sector dealer-positioning analysis, short recap videos (a few minutes each) after major market moves, and intraday level commentary — for education only

## Optional

- [Discord login](https://yehangshe.com/api/auth/discord): User authentication entry