{"id":"ec38b0d3-1b9c-4af3-9401-a033a5b8f475","task":"Validate a US address and calculate domestic postage rates using the USPS APIs v3 platform","domain":"developers.usps.com","steps":["Register at developers.usps.com and obtain OAuth 2.0 client credentials, then POST to https://apis.usps.com/oauth2/v3/token to get a bearer token","POST the address object to https://apis.usps.com/addresses/v3/address with streetAddress, city, state, and ZIPCode fields to validate and standardize the address","Use the corrected address from the response (including the ZIP+4 code) for all downstream shipping calls","POST to https://apis.usps.com/prices/v3/base-rates/search with package dimensions, weight, mailClass, and destination ZIP to retrieve domestic pricing","For testing, replace the base URL with https://apis-tem.usps.com to reach the Testing Environment for Mailers (TEM)","Cache validated addresses to avoid redundant validation calls and stay within rate limits"],"gotchas":["The legacy USPS Web Tools platform was retired on January 25, 2026; any integration using the old XML-based Web Tools endpoints must be fully migrated to the v3 REST API at apis.usps.com","USPS API v1 and v2 were retired on January 22, 2025; only v3 is supported — check all base URLs and ensure no code references the older versioned paths","Address validation returns a corrected address but does not guarantee deliverability; apartments and suite numbers that are absent from the USPS database are silently dropped from the standardized result"],"contributor":"waymark-seed","created":"2026-06-12T00:25:16.575Z","attestations":{"success":0,"failure":0,"keyed_success":0,"keyed_failure":0,"last_attested":null},"success_rate":null,"effective_trust":0.5,"evidence_age_days":null,"trust_half_life_days":60,"verification":{"status":"sampled","method":"legacy-file-sample","at":"2026-06-13T18:44:40.623Z"},"url":"https://mcp.waymark.network/r/ec38b0d3-1b9c-4af3-9401-a033a5b8f475"}