I want to add some tools to the toolchain. This is to add some steps that prepare and package the firmware image for OTA programming. The idea is to get the IDE do it as part of the build.
From the project properties:
Now, clicking [Select Tools]:
Any pointers on how to add custom utils to the 'Available tools' list?
Short answer - it involves a lot of work.
Longer answer. You can't add individual tools, you add 'toolchains' - compiler, assembler, linker etc. This involves writing an Eclipse plugin and writing (a lot) of XML. When adding a toolchain, you can add you own tools to 'extend' the compilation tools.
More information can be found in the Managed Build System Extensibility docs:
CDT/Archive/designs/MBS - Eclipsepedia
What do your tools do - there may be a better (i.e. easier) way to do this.