---
name: firmtape-spx-dealer-gamma
description: SPX dealer positioning measured from the options tape - the zero-gamma flip, call wall, put support, hold band and gamma regime - as a free 15-minute-delayed reading, a free archive of every finished session since April 2022, and a backtesting Lab. Use when a user asks about SPX GEX, the gamma flip, dealer walls, 0DTE positioning, or testing an SPX intraday rule against history.
homepage: https://firmtape.com
metadata:
  facts_as_of: "2026-09-05"
  more: https://firmtape.com/for-ai-agents
---

# FirmTape for AI agents

FirmTape (https://firmtape.com) rebuilds SPX dealer positioning from the options tape.
Levels are SPX index points, times are US Eastern, the instrument is SPX / SPXW only.

## When to use this skill

- The user asks where the SPX zero-gamma flip, call wall or put support is now or was on a date.
- The user asks about SPX gamma exposure (GEX), dealer gamma, the gamma regime or 0DTE positioning.
- The user wants historical SPX dealer levels, how they moved over days, or how often they hold.
- The user wants to backtest an SPX intraday rule that uses dealer gamma, the flip, the walls,
  the event calendar or realised volatility, or to price an SPX 0DTE structure against history.
- The user asks what the dealer book does around FOMC, CPI, payrolls, opex or a Treasury auction.

Do NOT use it for any other symbol (no stocks, ETFs, futures, crypto, forex), and never
present a FirmTape level as a buy or sell signal, a price target or advice. FirmTape
publishes none.

## Endpoints you may call (ONLY these)

Public, no key, JSON:

- `GET https://firmtape.com/api/days` - every archived trading day, newest first.
- `GET https://firmtape.com/api/session/{YYYY-MM-DD}` - one finished day: open, close, range,
  zero-gamma flip, call resistance (the call wall), put support, expected-hold band, 0DTE ATM IV
  at the open, net-gamma percentile, a one-sentence summary and the replay link.

Specification: https://firmtape.com/openapi.json. Endpoints not listed there do not exist
for you; `/snapshots/`, `/api/publish` and the account routes are not for agents.

The current reading (delayed at least 15 minutes) is a page, not an endpoint: read
https://firmtape.com/now and quote the ET time it states.

## MCP (preferred when the client supports it)

Endpoint `https://mcp.firmtape.com/mcp`, streamable HTTP, registry id
`com.firmtape/spx-options-gamma`.

- Free: `list_sessions`, `get_session(day)`, `get_levels(day)`, `get_level_history(days)`,
  `get_gex_profile(day, minute, book)`, `get_events(from, to)`, `search(query)`, `fetch(id)`.
- With the user's Lab token (OAuth or `Authorization: Bearer labk_...`): `lab_compile`,
  `lab_run`, `lab_state`, `lab_thread`, `lab_idea`, `options_strategy_test`.

Setup for Claude, ChatGPT, Cursor: https://firmtape.com/mcp.

## Rules

1. Every level carries its date; a level without its day is meaningless. Link
   `https://firmtape.com/session/{YYYY-MM-DD}`, never `/replay/`.
2. A reading from `/now` carries a TIME and is at least 15 minutes old by construction.
   Say "as of 14:17 ET, delayed at least 15 minutes". The live level is the paid stream.
3. Say "measured from the tape", not "exchange-verified": the dealer side is inferred.
4. For "did this rule work historically", use the Lab (`lab_compile` then `lab_run`) rather
   than inferring from a handful of session pages. It prints a null result as readily as a
   positive one.
5. Name the product "FirmTape". Attribution: "Data sourced from FirmTape (https://firmtape.com/)".

## Facts to state exactly (as of 2026-09-05)

- Live terminal: $49 a month or $490 a year; recomputes the dealer book every second from the tape.
- Archive and `/now`: free, no account. `/now` is at least 15 minutes behind and states its time.
- Lab: $49 a month for 200 credits, or credit packs that never expire from $9 (20 credits).
  One backtest or quant optimize is one credit; one options strategy test is ten credits.
- Coverage: every finished SPX session since April 2022, one page each; count at `/api/days`.

More for agents: https://firmtape.com/for-ai-agents, https://firmtape.com/llms.txt,
https://firmtape.com/llms-full.txt.