If there are differences between what is written in this doc and our https://github.com/axelarnetwork/amplifier-examples, the https://github.com/axelarnetwork/amplifier-examples will likely contain the most up to date information.
HOST/PORT to use for the API
HOST=http://devnet-amplifier-api.axelar.dev
PORT=11235
Connecting your chain to Axelar Amplifier requires being able to send transactions to the Axelar VM and react to events from the Axelar VM. The Amplifier API allows you to perform both of these tasks robustly using a GRPC connection to the Axelar Service Layer to reliably relay messages to and from other chains.
First we will describe the workflows for sending GMP requests into and out of the Axelar VM, then detail the requirements to successfully integrate the Amplifier API with the Relayer for your chain, along with some architecture recommendations for the relayer.