In a few clicks in the Console, you can enable SHAKEN/STIR on your outgoing calls that deliver a trust indicator on the called party's phone.
You are considered a direct customer if your employees are responsible for making the calls. This includes BPOs.
You are considered an ISV (independent software vendor) if your customers are responsible for making the calls using your product.
For ISVs, there is a REST API available to allow you to pass your customer's business information directly to Twilio to get vetted so your customers can also get highest attestation under SHAKEN/STIR.