What automation solutions are there for the free version of ESXi 5.x? For example, you have a close-to-zero budget and want to automate the creation of VMs, checking for VMware tools, etc. using scripting or workflows.
PowerCLI traditionally has required vCenter Server - is this still the case?
Does vCLI work with free ESXi?
Has some third party created an open source automation solution that plugs into multiple free ESXi 5.x servers and uses the APIs to manage them without vCenter Server?
Unfortunately the API of the free ESXi Hypervisor is restricted, so your options are very limited. Although you mentioned a small budget, you may consider to get an Essentials license to get rid of these restrictions.
Okay thanks- it seems though that if you could hit the APIs with the C-sharp vsphere client application and create a VM why wouldn't you be able to hit those same APIs from a third-party product - and why wouldn't someone have created a product that could do this?
There is a nice collection of scripts on virtuallyGhetto: vGhetto Script Repository
You can automatise a lot of things with them (i.e. I use ghettoVCB started by cron to auto-backup my VMs).
Can I use these scripts to manage VMs on a free ESXi host? Create a VM, check how much RAM a VM is configured with, how many vCPUs it has, power down a VM, power on a VM, etc? What scripting language are they in? Perl, vCLI, esxcli?
Those I use work on free ESXi too. And when you click on the bottom link you see they are sorted out (perl, php, python, bash, etc).