{"uid":"cap_a46KwcXN7NlRSjYQeMrg2","slug":"geo402-great-circle-distance-163dd07a","name":"geo402 Great-Circle Distance","description":"Pay-per-call geolocation utility for AI agents: geocoding, reverse geocoding, timezone lookup, and great-circle distance. No API key, no subscription — agents pay per request via x402 (Base/USDC) or MPP (Tempo/pathUSD).","url":"https://geo402.alogos.xyz/v1/distance","method":"GET","headers":{},"bodySchema":{"type":"object","required":["lat1","lat2","lon1","lon2"],"properties":{"lat1":{"type":"number","description":"Start latitude in decimal degrees."},"lat2":{"type":"number","description":"Destination latitude in decimal degrees."},"lon1":{"type":"number","description":"Start longitude in decimal degrees."},"lon2":{"type":"number","description":"Destination longitude in decimal degrees."},"unit":{"enum":["km","mi","m","nmi"],"type":"string","description":"Distance unit: kilometers, miles, meters, or nautical miles."}}},"responseSchema":{"type":"object","properties":{"lat1":{"type":"number"},"lat2":{"type":"number"},"lon1":{"type":"number"},"lon2":{"type":"number"},"unit":{"type":"string"},"bearing":{"type":"number"},"distance":{"type":"number"},"distanceKm":{"type":"number"},"distanceMi":{"type":"number"}},"additionalProperties":true},"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_F0NuNfFl0s5lu164_fXiR","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":"Calculates the great-circle (shortest spherical) distance between two geographic coordinates, returning the result in the specified unit.","exampleAgentPrompt":"What's the great-circle distance in kilometers between New York City (40.7128° N, 74.0060° W) and London (51.5074° N, 0.1278° W)?","exampleUseCases":null,"resultDescription":"Returns the computed great-circle distance between the two coordinate pairs, expressed in the requested unit (e.g., kilometers, miles, or nautical miles). The response is a numeric distance value along the shortest spherical path between the two points.","failureModes":["Missing required parameters (lat1, lon1, lat2, lon2) returns a 400 error","Out-of-range latitude (outside -90 to 90) or longitude (outside -180 to 180) may return a validation error","Invalid or unsupported unit string may fall back to a default unit or return an error","Payment not provided or insufficient USDC/pathUSD triggers a 402 Payment Required response","Network timeout or server unavailability returns a 5xx error"],"whenToPreferThis":"Use this endpoint when an AI agent needs a fast, lightweight, pay-per-call computation of the straight-line (great-circle) distance between two known coordinate pairs, without needing geocoding or address resolution. Ideal for scenarios where coordinates are already known and only the distance metric is needed. Prefer over subscription-based geospatial APIs when usage is occasional or cost-per-call billing is preferred.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-15T06:41:01.089Z","isFirstParty":false}