Step 4 of 6

Position Sizing & Risk Check

A pre-trade checklist team that does the math on risk and checks your rules before you act.

The problem

Oversizing turns an ordinary wrong call into account-level damage. People skip the math or break their own rules in the moment. This team does the arithmetic on your own risk rules and acts as the checklist pilot before any trade. It applies YOUR rules; it never chooses them for you.

The team

Rules Keeper: Holds your written risk rules and checks the proposed trade against each one.
Risk Calculator: Does the position-size and worst-case math, showing its work.
Pre-Mortem: Imagines the trade already failed and lists the likely reasons, so you can plan for them.

How the agents hand off work

The thesis and open questions from step 3 arrive with a proposed trade plan.
Rules Keeper checks your rules; any RULE BREAK stops the process.
Risk Calculator does the sizing math on your numbers.
Pre-Mortem lists failure modes. Everything gets saved into your Trade Journal (step 5).

Copy-paste prompts

Rules Keeper

Holds your written risk rules and checks the proposed trade against each one.

You are my Rules Keeper. These are MY written risk rules (do not change them):
[e.g. max risk per trade = 1% of account; max 5 open positions; max 20% in one sector; no trades within 2 days of earnings; no averaging down]
Proposed trade: [asset, direction, planned entry, planned exit/stop, planned size]
Current open positions: [list]
For each rule return PASS / FAIL / CAN'T TELL with a one-line reason. If any rule FAILS, say clearly "RULE BREAK" at the top. Do not give opinions on the trade itself.

Risk Calculator

Does the position-size and worst-case math, showing its work.

You are the Risk Calculator. Show all arithmetic step by step.
Account size: [$]. Max risk per trade (my rule): [%].
Planned entry: [price]. Planned exit if wrong: [price]. Instrument notes: [e.g. contract multiplier, fees, leverage].
Compute: dollar risk allowed, risk per unit, max units, total position value, % of account, and the loss if price gaps 2x past my exit.
Then re-check the math a second way and confirm the numbers match. Do not recommend whether to trade.

Pre-Mortem

Imagines the trade already failed and lists the likely reasons, so you can plan for them.

You are running a pre-mortem. Imagine it's [time horizon] from now and this trade lost money. Write the 5 most likely reasons, ordered by likelihood, each with an early warning sign I could watch for.
Then list: what I will do if each warning sign appears (as questions for me to answer, not instructions).
Trade + thesis + Judge's open questions:
[paste]

Works with

Grok Bot, ChatGPT, Claude, Gemini, or any chat assistant or agent framework that supports multiple conversations, projects, or sub-agents. Tip: run each role in its own chat, project, or sub-agent so they don't blend together. Assistants with web search give better results for research roles.

Related roles & tools

Roles: Options Strategist (Educational), Risk Officer, Data Checker · all roles

Tools: ChatGPT, LangGraph, OpenAI Agents SDK, Alpha Vantage, Tiingo, Portfolio Visualizer · full directory

Tips

Write your risk rules once, in a doc, and paste them in every time. Don't retype from memory.
Always verify the calculator's arithmetic yourself or in a spreadsheet; LLMs make math errors.
A rule you break 'just this once' is not a rule.

Limitations

Language models can make arithmetic mistakes, so double-check every number.
Gaps, slippage, fees, leverage and margin rules vary by instrument and account; the agent only knows what you tell it.
This is a checklist aid. It is not risk management advice and does not know your full financial situation.

Educational only. Not financial advice. The Agentic Trader teaches how to organize AI agents around your own research and review process. Nothing here is a recommendation to buy, sell, or hold any security or asset. We do not endorse any broker, platform, or asset. AI output can be wrong, so verify everything and make your own decisions. Trading and investing involve risk of loss.

← Step 3: Thesis Check & Devil's Advocate | Step 5: Trade Journal →