aid: prelude-so url: https://raw.githubusercontent.com/api-evangelist/prelude-so/refs/heads/main/apis.yml name: Prelude kind: company description: >- Prelude is a phone and email verification API - "the trust layer between your signups and your business." Its Verify API creates and checks one-time passcodes (OTP) across SMS, WhatsApp, RCS, Viber, and voice in 230+ countries, with smart multi-provider routing and built-in anti-fraud. Alongside Verify, Prelude offers Notify (transactional messaging), Lookup / Intel (phone number intelligence - line type, carrier, ported and temporary flags, CNAM), and Watch (anti-fraud risk prediction and feedback). The public REST API v2 lives at https://api.prelude.dev/v2 with Bearer API-key auth and official SDKs for Python, Node.js, Java, and Go. Prelude positions itself as a developer-first alternative to Twilio Verify. image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/apis-json-logo.jpg tags: - Number Verification - Phone Verification - OTP - Authentication - Anti-Fraud - Two-Factor Authentication - SMS - Phone Number Lookup created: '2026-07-11' modified: '2026-07-11' specificationVersion: '0.19' apis: - aid: prelude-so:prelude-so-verification-api name: Prelude Verification API tags: - Number Verification - Phone Verification - OTP - Authentication image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/apis-json-logo.jpg humanURL: https://docs.prelude.so/verify/v2/api-reference/create-or-retry-a-verification baseURL: https://api.prelude.dev/v2 properties: - url: https://docs.prelude.so/verify/v2/documentation/introduction type: Documentation - url: https://docs.prelude.so/verify/v2/api-reference/create-or-retry-a-verification type: APIReference - url: openapi/prelude-so-openapi.yml type: OpenAPI - url: collections/prelude-so.postman_collection.json type: PostmanCollection - url: collections/prelude-so.opencollection.json type: OpenCollection description: >- Create or retry a one-time passcode (OTP) verification for a phone number or email address and check the submitted code. Delivery spans SMS, WhatsApp, RCS, Viber, and voice with smart multi-provider routing, optional PSD2 dynamic linking on check, and inline anti-fraud signals. POST /verification and POST /verification/check. - aid: prelude-so:prelude-so-lookup-api name: Prelude Lookup API tags: - Phone Number Lookup - Number Intelligence - Carrier image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/apis-json-logo.jpg humanURL: https://docs.prelude.so/intel/v2/api-reference baseURL: https://api.prelude.dev/v2 properties: - url: https://docs.prelude.so/intel/v2/api-reference type: APIReference - url: openapi/prelude-so-openapi.yml type: OpenAPI - url: collections/prelude-so.postman_collection.json type: PostmanCollection - url: collections/prelude-so.opencollection.json type: OpenCollection description: >- Phone number intelligence (Intel). Look up an E.164 number to get its line type (mobile, fixed_line, voip, etc.), current and original carrier / network info (name, MCC, MNC), ported and temporary flags, and optionally the caller name (CNAM). Useful for number validation and pre-verification fraud screening. GET /lookup/{phone_number}. - aid: prelude-so:prelude-so-watch-api name: Prelude Watch Anti-Fraud API tags: - Anti-Fraud - Risk Scoring - Fraud Detection image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/apis-json-logo.jpg humanURL: https://docs.prelude.so/watch/v2/api-reference baseURL: https://api.prelude.dev/v2 properties: - url: https://docs.prelude.so/watch/v2/api-reference type: APIReference - url: openapi/prelude-so-openapi.yml type: OpenAPI - url: collections/prelude-so.postman_collection.json type: PostmanCollection - url: collections/prelude-so.opencollection.json type: OpenCollection description: >- Anti-fraud (Watch). Predict whether a signup identifier is legitimate or suspicious using device, network, and behavioral signals, then send feedback about what actually happened in your verification flow so the model improves. POST /watch/predict, POST /watch/feedback, and a documentation-referenced dispatch-events endpoint (modeled). - aid: prelude-so:prelude-so-transactional-api name: Prelude Transactional Messaging API tags: - Transactional Messaging - SMS - Notifications image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/apis-json-logo.jpg humanURL: https://docs.prelude.so/notify/v2/api-reference baseURL: https://api.prelude.dev/v2 properties: - url: https://docs.prelude.so/notify/v2/api-reference type: APIReference - url: openapi/prelude-so-openapi.yml type: OpenAPI - url: collections/prelude-so.postman_collection.json type: PostmanCollection - url: collections/prelude-so.opencollection.json type: OpenCollection description: >- Transactional messaging (Notify). Send a template-based message to a recipient over the best available channel (SMS, RCS, or WhatsApp), with variables, scheduling, expiry, delivery callbacks, media documents, and auto-retries. POST /notify. common: - type: AgenticAccess url: agentic-access/prelude-so-agentic-access.yml - type: Authentication url: authentication/prelude-so-authentication.yml - type: LinkedIn url: https://www.linkedin.com/company/prelude-so - type: Website url: https://prelude.so - type: Documentation url: https://docs.prelude.so - type: Plans url: plans/prelude-so-plans-pricing.yml - type: RateLimits url: rate-limits/prelude-so-rate-limits.yml - type: FinOps url: finops/prelude-so-finops.yml - url: https://prelude.so/blog type: Blog maintainers: - FN: Kin Lane email: kin@apievangelist.com