micro-snitch

Install command: 
brew install --cask micro-snitch

Name: Micro Snitch

Monitors and reports any microphone and camera activity

https://www.obdev.at/products/microsnitch/index.html

Cask JSON API: /api/cask/micro-snitch.json

Cask code: micro-snitch.rb on GitHub

Current version: 1.6.1

Requirements: macOS >= 10.15

Analytics:

Installs (30 days)
micro-snitch 39
Installs (90 days)
micro-snitch 135
Installs (365 days)
micro-snitch 554