> For the complete documentation index, see [llms.txt](https://drop-cowboy.gitbook.io/drop-cowboy-docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://drop-cowboy.gitbook.io/drop-cowboy-docs/api.md). # API - [Sending RVM (Ringless Voicemail)](https://drop-cowboy.gitbook.io/drop-cowboy-docs/api/sending-rvm-ringless-voicemail.md): Drop Cowboy allows you to send ringless voicemail containing static audio or dynamic AI generated audio. - [Send RVM Using the SDK](https://drop-cowboy.gitbook.io/drop-cowboy-docs/api/sending-rvm-ringless-voicemail/send-rvm-using-the-sdk.md): Sends a ringless voicemail to a phone number using the Drop Cowboy SDK - [API Endpoint](https://drop-cowboy.gitbook.io/drop-cowboy-docs/api/sending-rvm-ringless-voicemail/api-endpoint.md) - [Webhooks](https://drop-cowboy.gitbook.io/drop-cowboy-docs/api/sending-rvm-ringless-voicemail/webhooks.md): Drop Cowboy will notify you via webhook by http POST to the URL you specify in your API request. You will receive JSON content containing the delivery status of every voicemail you attempt to send. - [Sending Limits](https://drop-cowboy.gitbook.io/drop-cowboy-docs/api/sending-rvm-ringless-voicemail/sending-limits.md) - [Debugging](https://drop-cowboy.gitbook.io/drop-cowboy-docs/api/sending-rvm-ringless-voicemail/debugging.md): Drop Cowboy's portal contains tools to help you debug your webhooks and API requests - [Sending SMS (Text Message)](https://drop-cowboy.gitbook.io/drop-cowboy-docs/api/sending-sms-text-message.md): Drop Cowboy allows you to send text messages. - [Send SMS Using the SDK](https://drop-cowboy.gitbook.io/drop-cowboy-docs/api/sending-sms-text-message/send-sms-using-the-sdk.md) - [API Endpoint](https://drop-cowboy.gitbook.io/drop-cowboy-docs/api/sending-sms-text-message/api-endpoint.md) - [Webhooks](https://drop-cowboy.gitbook.io/drop-cowboy-docs/api/sending-sms-text-message/webhooks.md): Drop Cowboy will notify you via webhook by http POST to the URL you specify in your API request. You will receive JSON content containing the delivery status of every voicemail you attempt to send. - [Trusted Brands](https://drop-cowboy.gitbook.io/drop-cowboy-docs/api/trusted-brands.md): Businesses must register their brand(s) with Drop Cowboy - [Listing ALL Brands](https://drop-cowboy.gitbook.io/drop-cowboy-docs/api/trusted-brands/listing-all-brands.md) - [Audio Recordings](https://drop-cowboy.gitbook.io/drop-cowboy-docs/api/audio-recordings.md): Customers upload audio recordings through the Drop Cowboy portal. - [Listing APPROVED Audio Recordings](https://drop-cowboy.gitbook.io/drop-cowboy-docs/api/audio-recordings/listing-approved-audio-recordings.md): You can retrieve a list of audio recordings that are approved for use with the Drop Cowboy API. - [Listing ALL Audio Recordings](https://drop-cowboy.gitbook.io/drop-cowboy-docs/api/audio-recordings/listing-all-audio-recordings.md): You can retrieve a list of audio recordings for use with the Drop Cowboy API. - [Return Calls / Caller ID](https://drop-cowboy.gitbook.io/drop-cowboy-docs/api/return-calls-caller-id.md): When sending ringless voicemail, Drop Cowboy will display a phone number / caller ID for contacts to call back when responding to a voicemail. - [Shared Numbers with Call Forwarding](https://drop-cowboy.gitbook.io/drop-cowboy-docs/api/return-calls-caller-id/shared-numbers-with-call-forwarding.md): Drop Cowboy maintains a shared pool of phone numbers available to all Drop Cowboy customers to use. - [Private Number Pools](https://drop-cowboy.gitbook.io/drop-cowboy-docs/api/return-calls-caller-id/private-number-pools.md): Drop Cowboy allows customers to maintain pools of phone numbers that are private to their Drop Cowboy account and not shared with other Drop Cowboy customers. - [Explicit Caller ID (Requires Bring Your Own Carrier)](https://drop-cowboy.gitbook.io/drop-cowboy-docs/api/return-calls-caller-id/explicit-caller-id-requires-bring-your-own-carrier.md): Drop Cowboy customers using their own SIP trunks with our Bring Your Own Carrier solution are able to explicitly set the caller\_id property of the RVM API request. - [Listing Private Number Pools](https://drop-cowboy.gitbook.io/drop-cowboy-docs/api/return-calls-caller-id/listing-private-number-pools.md): Retrieve a list of all private number pools in your Drop Cowboy account - [Contact Lists](https://drop-cowboy.gitbook.io/drop-cowboy-docs/api/contact-lists.md): The Contact Lists API allows you to manage groups of contacts for messaging, segmentation, or campaign targeting. - [Create Contact List](https://drop-cowboy.gitbook.io/drop-cowboy-docs/api/contact-lists/create-contact-list.md) - [Rename Contact List](https://drop-cowboy.gitbook.io/drop-cowboy-docs/api/contact-lists/rename-contact-list.md) - [Append Contacts To List](https://drop-cowboy.gitbook.io/drop-cowboy-docs/api/contact-lists/append-contacts-to-list.md) - [Get Contact List Details](https://drop-cowboy.gitbook.io/drop-cowboy-docs/api/contact-lists/get-contact-list-details.md) - [Delete Contact List](https://drop-cowboy.gitbook.io/drop-cowboy-docs/api/contact-lists/delete-contact-list.md) --- # Agent Instructions This documentation is published with GitBook. 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