The GEXStream REST API

Key-authenticated, server-to-server access to the same gamma-exposure metrics the dashboard shows — a live snapshot per ticker, and hourly history for research.

Overview

Two endpoints, both read-only:

The base URL is https://gexstream.com. All responses are JSON. Only tickers in the tracked screener universe are served — anything else is a 404.

Get your key from the app: sign in, open the account menu, choose api, and create a key in the API Access section. The key is shown exactly once — store it in a secrets manager, not in code.

Authentication

Send your key in the X-API-Key header on every request. Keys are never accepted as query parameters — they must not appear in URLs or server logs. A User-Agent header is required; requests without one are rejected with 400.

• One active key per account. Creating a new key (rotation) invalidates the old one immediately.
• Revoking a key takes effect immediately, not at a cache expiry.
• One client at a time: your key binds to the first client address that uses it. Requests from a second address get a 409 with retry_after_seconds until the binding lapses (10 minutes idle) or you release it from the account modal. IPv6 clients are bound at their /64 prefix.

The latest computed metrics for one ticker. Values refresh on a rolling cache and may be up to 5 minutes old — polling faster than that returns the same data.

Example response (Quant; Flow responses omit the dex/vex/cex objects entirely):

{
  "ticker": "SPY",
  "asof": "2026-07-30T15:42:11Z",
  "spot": 585.42,
  "gex":  { "net": 1.24e9, "ratio": 0.85, "zero_gamma": 580.0,
            "max_strike": 590.0, "min_strike": 570.0 },
  "vgex": { "net": 4.1e8, "ratio": 0.72, "zero_vgamma": 582.0,
            "max_strike": 590.0, "min_strike": 575.0 },
  "flow": { "ratio": 0.92, "net": -1.4e6 },
  "iv":   { "call": 0.142, "put": 0.163, "skew": -0.021 },
  "dex":  { "net": 2.2e9, "ratio": 0.71, "zero_delta": 578.0,
            "max_strike": 585.0, "min_strike": 560.0 },
  "vex":  { "net": -3.0e8, "ratio": 0.31, "zero_vanna": 583.0,
            "max_strike": 600.0, "min_strike": 570.0 },
  "cex":  { "net": 1.1e8, "ratio": 0.64, "zero_charm": 581.0,
            "max_strike": 585.0, "min_strike": 575.0 },
  "oi":   { "total": 1.8e7, "ratio": 0.61, "max_strike": 600.0,
            "min_strike": 550.0, "pct_chg": 1.4 }
}

• spot is omitted (not zero) when no fresh price is available — it is only served from the last 15 minutes.
• oi.pct_chg is omitted until the prior-session baseline is known.
• The response schema only ever grows — fields are added, never renamed or removed.

Hourly history for one ticker. One query parameter: days, which must be 30, 60, or 90 (default 90). Any other value is a 400.

Example response (Quant; Flow rows carry gex/vgex/flow/iv/volume/oi plus spot, and omit the dex/vex/cex objects entirely; the same family split as the snapshot):

GET /api/v1/history/SPY?days=30

{
  "ticker": "SPY",
  "resolution": "1h",
  "days": 30,
  "rows": [
    {
      "t": "2026-07-01T14:00:00Z",
      "spot": 578.10,
      "gex":  { "net": 9.8e8, "ratio": 0.79, "zero_gamma": 574.0,
                "max_strike": 580.0, "min_strike": 565.0 },
      "vgex": { ... },
      "flow": { "ratio": 0.58, "net": 2.1e6 },
      "iv":   { "call": 0.151, "put": 0.170, "skew": -0.019 },
      "volume": { "calls": 812345, "puts": 640321 },
      "dex": { ... }, "vex": { ... }, "cex": { ... },
      "oi":  { "total": 1.7e7, "ratio": 0.59,
               "max_strike": 600.0, "min_strike": 550.0 }
    },
    ...
  ]
}

• Rows are hourly buckets; t is the start of the hour the row covers (UTC, RFC 3339). A session's last row starts one hour before the close (15:00 ET, which is 19:00Z in daylight time and 20:00Z in standard time; earlier on a half day), and no row starts at or after the close. New data lands hourly.
• volume (per-hour call/put volume sums) exists only in history, and oi.pct_chg exists only in snapshots.
• A family object is omitted from a row when that hour has no data for it.

Field reference

Metrics are grouped into family objects. Your tier decides which families you receive — a family you are not entitled to is absent, never zeroed. For what each metric means and how it is computed, see the metrics documentation.

spot and asof/t appear at the top level for all tiers. On an expiration day, vex and cex stop being computable about 5 minutes before the close; until the next session they hold their last computed value.

Limits & quotas

• Trial accounts have no API access. The API requires an active paid Flow or Quant subscription; keys cannot be created during a trial. Accounts in a past-due grace period keep access.
• Daily quotas reset at midnight US/Eastern (calendar day, not a rolling 24 hours).
• Only successful (2xx) responses consume quota — errors and rejections cost you nothing.
• The distinct-ticker count is cumulative for the day: once a ticker is counted, repeat requests for it are always allowed; a new ticker past the cap is refused even with request quota remaining.

Every 200 (and daily-quota 429) carries your remaining budget:

Freshness & asof

• Snapshot: values may be up to 5 minutes old. Polling faster than once per ~5 minutes per ticker returns the same underlying data.
• History: hourly buckets; new rows land hourly.
• asof is the server time the response was generated (UTC, RFC 3339). It is not a data timestamp: the metrics behind it may be up to the cache age older. Use it to order and de-duplicate your own pulls, not to timestamp market events.
• In history rows, t is the data timestamp: the start of the hour the row aggregates.
• Metrics are computed during US market hours; outside them, snapshots serve the last computed state.

Errors

Every failure returns a JSON envelope with an error message, plus retry_after_seconds on 409 and resets_at on daily-quota 429s. Checks run in a fixed order — the table below is that precedence, top to bottom (e.g. a bad method on a bound-elsewhere key is a 405, not a 409):

Terms of use

Accepted when you create a key; the full Terms and Conditions (Section 14) govern. In summary:

• Personal use only. Your subscription and your key are for you, not for a product, team, or service.
• No redistribution. Do not resell, relay, or share data obtained through the API.
• No public display of API-derived data — no public dashboards, feeds, bots, or posts built on it.
• One client at a time. The binding limit above is a term, not just a mechanism.
• Keys are revocable at our discretion, at any time and without notice.
• API responses may contain key-specific identifying characteristics.

Connect Claude or ChatGPT to your GEXStream account and ask about gamma exposure in plain language. The assistant calls read-only GEXStream tools through the Model Context Protocol (MCP). You connect it by signing in and approving access on a GEXStream consent screen (OAuth): no API key is needed, and the assistant never sees your password. A connection lasts up to 90 days, or until it goes 30 days without use, and resetting your GEXStream password disconnects every assistant; the assistant then asks you to reconnect.

• Claude (web and desktop): add GEXStream as a custom connector. Open the prefilled connector form, confirm it, then connect and approve access on the GEXStream consent screen. On Claude Team and Enterprise plans, only organization Owners can add custom connectors.
• Claude Code: add the server from a terminal, then run /mcp inside Claude Code, select gexstream and choose Authenticate. Because Claude Code runs on your computer, the consent screen says so; approve only a connection you started yourself.

• ChatGPT: turn on developer mode, add a new connector with the server URL above and OAuth as its authentication, then approve access on the GEXStream consent screen.

The assistant can call five tools, all read-only:

• Limits are shared with the REST API. The snapshot and history tools draw on the same daily budgets as your API key: the same snapshot and history request quotas in the limits table, and the same distinct-ticker breadth (Flow 2, Quant 4 per US Eastern day). There is one budget per account, however many assistants you connect.
• An assistant may make several tool calls to answer one question, so a budget can run down faster than the number of questions you ask. Ask it to call get_usage to see what is left.
• Up to three connections per account. Each assistant is one connection, and so is each computer running Claude Code. Connecting another disconnects the oldest. A connector removed only inside the assistant still counts until you disconnect it in the account menu.
• Eligibility is the same as for the API: a paid Flow or Quant subscription. Trials are excluded.
• What is shared: the market data the assistant requests and your daily usage. The assistant cannot change your account, plan or settings, and never receives your password or payment information. Anthropic and OpenAI process tool results under their own terms and privacy policies.
• Personal use only. The Terms and Conditions apply to connector data as they do to the API: do not share or publicly display GEXStream data, including in shared chats, links, projects or published files.
• To disconnect, open the account menu, choose manage account, and use Disconnect in the AI assistants row. That is the reliable way to revoke access: removing the connector in your assistant's settings may not notify GEXStream, so do both if you want the assistant's stored access ended immediately.