Type: DirPath | Multiple: No | Default: “<Project>/include

The path to project’s default header files. PlatformIO uses it for the pio run command. The default value is include meaning an include directory located under the root directory of the project. This path will be added to CPPPATH of the build environment.

If you need to add extra include directories to CPPPATH scope, please use build_flags with -I /path/to/extra/dir option.

This option can also be configured by the global environment variable PLATFORMIO_INCLUDE_DIR.