{"uid":"cap_B5iiVW7zF-soQj4PrhR4d","slug":"stableemail-create-0718fbda","name":"StableEmail Subdomain Inbox Create","description":"Create an inbox on your subdomain ($0.25). Max 100 inboxes, 500 messages each. Message content and attachments retained for 90 days.","url":"https://stableemail.dev/api/subdomain/inbox/create?utm_source=zero.xyz","method":"POST","headers":{},"bodySchema":{"type":"object","required":["subdomain","localPart"],"properties":{"forwardTo":{"type":"string","format":"email","pattern":"^(?!\\.)(?!.*\\.\\.)([A-Za-z0-9_'+\\-\\.]*)[A-Za-z0-9_+-]@([A-Za-z0-9][A-Za-z0-9\\-]*\\.)+[A-Za-z]{2,}$"},"localPart":{"type":"string","pattern":"^[a-z0-9][a-z0-9._+-]{0,62}[a-z0-9]$","maxLength":64,"minLength":1},"subdomain":{"type":"string","allOf":[{"pattern":"^[a-z0-9][a-z0-9-]{1,28}[a-z0-9]$"},{"pattern":"^(?!.*--)"}]}}},"responseSchema":null,"example":null,"exampleRequest":null,"tags":["email","send","inbox","forwarding","subdomain","social"],"displayCostAmount":"0.25","displayCostAsset":"USDC","priceDynamic":false,"priceHint":null,"priceStatus":"priced","priceSource":"probe","requiresHandshake":false,"reviewCount":1,"rating":{"score":"0.00","successRate":"0.33","reviews":1,"stars":null,"state":"rated"},"availabilityStatus":"unknown","priceObserved":null,"sessionDeposit":null,"pricing":{"kind":"static","summary":"$0.25/call","primary":{"kind":"static","protocol":"mpp","network":"tempo","amountUsd":"0.25","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"mpp","network":"tempo","amountUsd":"0.25","per":"call","confidence":"exact"},{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.25","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_-5vle3kmPUEaxApwJ7iAb","protocol":"mpp","methodType":"crypto","chain":"tempo","mode":"charge","costAmount":"0.25","costPer":"request","priority":0,"asset":"0x20c000000000000000000000b9537d11c60e8b50","unit":"request","depositMicros":null,"planRef":null},{"uid":"pm_uKnLu2ZmhTahG3sIDrMqF","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.25","costPer":"request","priority":0,"asset":null,"unit":"request","depositMicros":null,"planRef":null}],"brandName":"StableEmail","brandSlug":"stableemail","brandBaseUrl":"https://stableemail.dev","brandDocsUrl":"https://stableemail.dev","whatItDoes":"Creates a new email inbox on a custom subdomain, optionally forwarding incoming mail to another address, for $0.25 USDC.","exampleAgentPrompt":"Create a new inbox called support@mycompany.stableemail.dev and forward any incoming mail to me@gmail.com.","exampleUseCases":null,"resultDescription":"Returns a confirmation that the inbox has been created on the specified subdomain with the given local part, along with inbox details such as the full email address and forwarding configuration. Up to 100 inboxes per subdomain, each storing up to 500 messages for 90 days.","failureModes":["Subdomain not owned or not verified — inbox creation rejected","localPart already exists on that subdomain — conflict error","Subdomain inbox limit of 100 reached — creation blocked","Invalid localPart format (must be lowercase alphanumeric with dots/dashes, 1-64 chars)","Invalid subdomain format (must be lowercase alphanumeric with hyphens, no double hyphens)","Invalid forwardTo email address format","Insufficient USDC balance for $0.25 payment","Payment failure or x402 protocol error"],"whenToPreferThis":"Use this endpoint when you need to programmatically create a new receiving inbox on a subdomain you already own on StableEmail, with optional forwarding to a real address. Prefer this over the basic stableemail.dev inbox buy endpoint when you have a custom subdomain and want inbox addresses on that subdomain rather than the shared stableemail.dev domain.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":3,"lastUsedAt":"2026-04-13T22:26:45.924Z","lastSuccessfullyRanAt":"2026-04-13T20:59:02.749Z","lastHealthCheckAt":"2026-10-11T18:32:00.535Z","isFirstParty":false,"canonicalSlug":"stableemail-create-0718fbda"}