{"uid":"cap_Hj81B0XBaRPG66tgh08bY","slug":"neuroterminal-position-size-calculator-966791d9","name":"Neuroterminal Position Size Calculator","description":"Paid HTTP endpoints for AI agents, settled in USDC on Base via the x402 protocol. No account, no API key — pay per call.","url":"https://api.neuroterminal.xyz/v1/position-size","method":"GET","headers":{},"bodySchema":{"type":"object","$schema":"https://json-schema.org/draft/2020-12/schema","required":["input"],"properties":{"input":{"type":"object","required":["type","method"],"properties":{"type":{"type":"string","const":"http"},"method":{"enum":["GET"],"type":"string"},"queryParams":{"type":"object","required":["winProbability","winAmount"],"properties":{"capital":{"type":"number"},"fraction":{"type":"number"},"winAmount":{"type":"number"},"lossAmount":{"type":"number"},"winProbability":{"type":"number"}}}},"additionalProperties":false},"output":{"type":"object","required":["type"],"properties":{"type":{"type":"string"},"example":{"type":"object"}}}}},"responseSchema":{"type":"json","example":{"verdict":"positive edge","kellyFraction":0.2,"suggestedStake":1000,"fractionalKelly":0.1,"breakEvenWinRate":0.5}},"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.01","displayCostAsset":"USDC","priceDynamic":false,"priceHint":null,"priceStatus":"priced","priceSource":"probe","requiresHandshake":false,"reviewCount":0,"rating":{"score":"0.00","successRate":"0.00","reviews":0,"stars":null,"state":"unrated"},"availabilityStatus":"unknown","priceObserved":null,"sessionDeposit":null,"pricing":{"kind":"static","summary":"$0.01/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.01","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.01","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_bPpKiG1X2IhL2S-053QCh","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.01","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Computes optimal bet/trade position size using the Kelly Criterion given win probability, win/loss amounts, and available capital","exampleAgentPrompt":"Using the Kelly Criterion, what's my optimal position size if I have $10,000 in capital, a 60% win probability, a potential win of $500, and a potential loss of $300? Show me the Kelly fraction and suggested stake.","exampleUseCases":[{"title":"Optimal stock trade sizing","prompt":"I'm considering a trade where I estimate a 65% chance of winning, the upside is $800, the downside is $400, and I have $20,000 in capital — what's the Kelly Criterion optimal position size and fractional Kelly stake I should use?"},{"title":"Sports bet bankroll management","prompt":"I want to bet on a game where I think there's a 55% chance of winning, the payout is $150 for every $100 I risk, and my bankroll is $5,000 — calculate the Kelly fraction and tell me how much I should wager."},{"title":"Options trade risk sizing","prompt":"Help me size an options position: I have $15,000 available, I estimate a 70% probability of success, my max gain is $2,000, and my max loss is $600 — what does Kelly say my stake should be, and what's the break-even win rate?"}],"resultDescription":"Returns a JSON object with: a verdict string (e.g. 'positive edge'), the full Kelly fraction, a suggested stake in dollar amount, a fractional Kelly value (typically half-Kelly for conservative sizing), and the break-even win rate required for the bet to have positive expected value.","failureModes":["Missing required parameters winProbability or winAmount returns a 400 error","Win probability outside 0-1 range may return invalid results or error","Negative capital or amounts may produce unexpected output","Network or payment failure via x402 protocol returns 402 Payment Required","Server unavailability returns 5xx error"],"whenToPreferThis":"Choose this endpoint when you need a mathematically rigorous, Kelly Criterion-based position sizing recommendation without setting up an account or API key. Ideal for agents handling trading, betting, or any capital allocation task where the user knows their edge (win probability) and payoff structure. At $0.01 per call via USDC on Base, it's suitable for on-demand, per-decision use rather than high-frequency bulk calculations.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-15T06:36:29.702Z","isFirstParty":false}