# A1ROUTES Developer

Customer documentation for Number Lookup and BusinessPhoneSystem (A1PBX). Messaging is coming soon. A1PBX examples require account/version confirmation.

- [Start building with A1ROUTES](https://developer.a1routes.com/docs/getting-started): Find your API, connect your account, and make your first request.
- [Authentication](https://developer.a1routes.com/docs/authentication): Use the right credentials for each A1ROUTES service.
- [Your first number lookup](https://developer.a1routes.com/docs/lookup/quickstart): Send an LRN request using your existing SIP account.
- [Look up a number](https://developer.a1routes.com/docs/lookup/lrn): Retrieve LRN information for a telephone number using your main SIP account API key.
- [Connect your BusinessPhoneSystem](https://developer.a1routes.com/docs/a1pbx/quickstart): Build against your own A1PBX account hostname.
- [Originate a call](https://developer.a1routes.com/docs/a1pbx/originate): Connect an existing extension to a destination number for CRM click-to-call workflows.
- [List call recordings](https://developer.a1routes.com/docs/a1pbx/recordings): Find recorded calls available to your A1PBX API account.
- [Download a recording](https://developer.a1routes.com/docs/a1pbx/recording): Retrieve the audio of an accessible recorded call by its recording identifier.
- [List call history](https://developer.a1routes.com/docs/a1pbx/call-history): Retrieve call detail records for reporting and integration with your business systems.
- [Get a call record](https://developer.a1routes.com/docs/a1pbx/call-record): Retrieve one call detail record accessible to your account.
- [List voicemail messages](https://developer.a1routes.com/docs/a1pbx/voicemail): Retrieve messages from mailboxes your integration is authorized to access.
- [Retrieve voicemail audio](https://developer.a1routes.com/docs/a1pbx/voicemail-audio): Retrieve an authorized voicemail message, including its available audio.
- [Add click-to-call to your CRM](https://developer.a1routes.com/docs/guides/click-to-call): Connect a CRM action to an existing A1PBX extension.
- [Retrieve recording audio](https://developer.a1routes.com/docs/guides/recording-audio): Find a recorded call and save its audio securely.
- [Synchronize call history](https://developer.a1routes.com/docs/guides/sync-call-history): Import customer call records into your reporting system.
- [Retrieve voicemail messages](https://developer.a1routes.com/docs/guides/voicemail-audio): Read authorized messages and decode available audio.
- [Handle errors and retries](https://developer.a1routes.com/docs/errors): Build predictable integrations without duplicating calls.
- [Pagination and limits](https://developer.a1routes.com/docs/pagination): Read datasets carefully across different API deployments.
- [OpenAPI specifications](https://developer.a1routes.com/docs/downloads): Download the customer-facing API contracts.
- [Changelog](https://developer.a1routes.com/docs/changelog): Changes to the A1ROUTES developer documentation.
- [Messaging API](https://developer.a1routes.com/docs/messaging): Messaging documentation is coming soon.