Calculate contract-based futures position sizes from a direction, entry, and stop-loss, using verified per-symbol contract specs (multiplier, tick size, tick value). Use when the user asks how many futures contracts to trade, wants to size a futures position (ES, NQ, ZB, GC, CL, 6E/E6, VX, BT, ...),

Futures Position Sizer Overview Shapiro pipeline step 4: convert a direction, entry price, and stop loss into a contract count, given an account risk budget and a verified contract spec (multiplier, tick size, tick value). This is a NEW, separate skill from position sizer futures contracts are leveraged, multiplier based instruments with wildly different dollar per point values (a $0.25 move is $12.50 on ES but $5.00 on NQ and $31.25 on ZB); reusing the equity share count sizer for futures would silently produce wrong position sizes. Two ways to size a trade: Mode A (explicit) : supply symbol direction entry stop directly. Mode B (gate handoff) : supply gate json <contrarian setup gate report entry . Direction and stop (the gate's invalidation level ) come from the gate's READY FOR PLAN report the sizer never sizes a setup the gate has not confirmed as READY, and never accepts an explicit direction / stop alongside gate json (the gate is authoritative when provided). entry is ALWAYS required, in both modes neither this skill nor the gate ever derives an entry price; the operator supplies it. When to Use After contrarian setup gate reaches READY FOR PLAN and you need a contract count for the confirmed direction and stop User asks "how many ES/NQ/GC/CL/... contracts should I trade?" User has a futures trade idea with a known entry and stop and wants risk based sizing User wants to check the verified contract spec (multiplier/tick size/tick value) for a symbol before sizing ( list specs ) Prerequisites Python 3.9+, standard library only no API keys, fully offline A direction, entry, and stop (mode A), or a contrarian setup gate JSON report with setup status: READY FOR PLAN (mode B) For a symbol outside the verified 23 market core table: its multiplier, tick size, and quote currency (all three, together) Workflow Step 1: Size the Position Mode A explicit: Mode B gate handoff: symbol may be omitted in mode B it is taken from the gate report. If both are given, they must match ( gate symbol mismatch otherwise). direction / stop are rejected alongside gate json (usage error, exit 2) pass one mode or the other, never both. Step 2: Read the Result sizing status Meaning SIZED contracts = 1; total risk usd / risk pct of account are the actual risk taken NO TRADE Never a crash always carries no trade reason . See the reason glossary below A NO TRADE result from risk below one contract still reports the full risk math (risk per contract, risk budget, stop distance) the account simply cannot afford one contract at this risk percentage and stop distance; widen the stop, increase risk %, or skip the trade. Step 3: Check Warnings warnings (top level list) never blocks sizing it flags audit worthy conditions: risk pct above 2 (risk above the 2% guideline), off tick grid entry / off tick grid stop (a non bond symbol's price is not exactly on the tick grid legitimate for a mid quote, but worth a second look). Step 4: Inspect the Verified Contract Spec Table Prints the full 23 market core table (multiplier, tick size, tick value, currency, exchange) sourced from official exchange contract spec pages see references/futures contract specs.md for the per row source URLs and verification dates. Worked Example: Bond Off Grid Guard (32nds Decimal) Bond/note futures (ZT, ZF, ZN, ZB) quote in fractions of a point (32nds, or 32nds of 32nds), commonly written with an apostrophe: 110'16 means 110 + 16/32 = 110.50 . Typing 110.16 instead reading the digits after the apostrophe as if they were decimal cents is a classic, silent, wrong money math mistake: 110.16 is not on the ZB tick grid ( 0.03125 = 1/32) at all. Every other symbol in the table quotes in plain decimal points an off grid price there (a mid quote, for instance) is only a soft off tick grid warning, never a rejection. Output Contract Writes futures position size <SYMBOL <as of .json to output dir when format json both ; format text both prints a formatted summary to stdout. as of defaults to today (this is an operator time sizing tool, not a backtest tool). Guardrails 1. Never sizes a position without an explicit stop. stop is required in mode A; mode B refuses to size ( gate not ready ) until the gate itself reports READY FOR PLAN with a valid invalidation level . 2. Floor, never round up exact by construction, no epsilon. contracts = floor(risk budget / risk per contract) is computed with exact rational arithmetic (Python's Fraction , not float division), so contracts risk per contract <= risk budget holds by construction no epsilon nudge, no float representation edge case, and no risk of ever exceeding the budget. Also rejected outright if the resulting count is economically implausible (an absurd input like a denormal scale multiplier override). Zero contracts is a legitimate, fail closed NO TRADE outcome, not an error. 3. Two fail closed classes, matched to who supplied the bad value. An operator caused problem (an explicit stop on the wrong side of entry , a stop closer than one tick, a bond price typed off the tick grid) is a usage error: exit 2, no report written. The identical class of problem on a value that came from the untrusted gate report file (mode B's stop) is instead a fail closed NO TRADE result: exit 0, a report IS written, naming the reason this never crashes on a bad or not yet ready gate file, matching every other skill in this pipeline. 4. Bond family off grid prices are a hard rejection, not a warning. ZT/ZF/ZN/ZB quote in 32nds/64ths notation; a price that doesn't land on the tick grid is almost certainly a notation mistype and would silently produce wrong money math if sized. Every other symbol only warns. 5. Margin is never computed. margin note is a static, never stale reminder margin requirements are broker and time dependent; this skill does not estimate them. 6. Currency aware. Every core table symbol is USD quoted (confirmed by a table wide unit test), including the CME FX futures whose contract SIZE is denominated in a foreign currency (e.g. B6's GBP 62,500) but which trade and settle in USD. A symbol quoted in a non USD currency (via contract currency override) requires an explicit fx rate there is no silent default. 7. Not investment advice. This skill performs risk based arithmetic on operator supplied or gate confirmed inputs; it does not recommend a trade, a direction, or an entry. Resources scripts/futures position sizer.py CLI: argument parsing, hardened gate json loading (unreadable / parse error incl. RecursionError / non finite via an iterative whole file scan), report generation scripts/futures sizing.py Pure sizing core: numeric validators, the verified 23 market contract spec table, risk math, the floor algorithm, tick grid guards, and gate report shape normalization references/futures contract specs.md The verified contract spec table with per row official source URLs and verification dates references/sizing methodology.md Formulas, the exact rational floor algorithm's rationale, the fail closed exit code convention, and worked examples (ES long, B6 short via gate handoff)

futures-position-sizer