Issue installing custom board file package

[dataisinfinite]

Hi everyone,

I'm developing a custom Arduino ESP32 core package. I have some Arduino robots based around the ESP32-WROOM-32D chip. It currently uses the esp32 dev board. Currently, I am downloading the espressif esp32 from the Arduino board manager. However, this file is very large and takes a while to download. I want to remove all the extra toolchains and other files not being used by me and keep only the necessary files to compile and run my bot. Then i want to host this custom board package myself on github and have a JSON which can be added to preferences so my custom board package can be downloaded and installed directly by Arduino board manager.

Current Status & The Problem:

IDE: Arduino IDE version , 2.3.6; OS: Windows 11

Installation: My package_ExoNaut_index.json (hosted on GitHub Pages) is successfully parsed by the IDE. The "ExoNaut ESP32 Core" platform and its declared tool dependencies (esp32-arduino-libs, xtensa-esp-elf-gcc, esptool_py, mkspiffs) appear to download and install correctly. The IDE logs show successful installation and configuration of all components.

https://github.com/RyanSpaceTrek/TestBoard

Tools are located in: packages/ExoNaut/tools/

Platform is in: packages/ExoNaut/hardware/esp32/1.0.0/

When I select my custom board ("ESP32 Dev Module (ExoNaut)") from the Tools menu and try to "Verify" or "Upload" any sketch, I get the error:
Missing FQBN (Fully Qualified Board Name)
Compilation error: Missing FQBN (Fully Qualified Board Name)

Troubleshooting Steps Taken:

platform.txt Modifications:

Commented out local tools.TOOL_NAME.path definitions for tools intended to be globally managed.

Updated compiler.path, compiler.sdk.path, and various tool command recipes (e.g., esptool_py, espota.py) to use {runtime.tools.TOOL_NAME.path}.

Ensured GDB path points to the xtensa-esp-elf-gcc tool's bin directory (debug.toolchain.path={runtime.tools.xtensa-esp-elf-gcc.path}/bin/).

OpenOCD paths (debug.server.openocd.*) currently point to {runtime.platform.path}/tools/openocd-esp32/... as OpenOCD is not yet listed as a separate tool in my package_ExoNaut_index.json (implying it would need to be bundled in the platform zip for now if JTAG debugging is used).

Platform-specific Python scripts like gen_esp32part.py are also referenced via {runtime.platform.path}/tools/... and are included in my platform .zip.

boards.txt Review:

My boards.txt defines the "ESP32 Dev Module (ExoNaut)" with various custom menu options.

I've particularly scrutinized the menu.UploadSpeed section, as it contained complex OS-specific definitions. I've tried simplifying this section and correcting the syntax for OS-specific labels and properties (e.g., using .os.windows= for labels and .property.os.windows= for properties) as per standard Arduino boards.txt conventions.

Has anyone encountered a similar "Missing FQBN" issue with a custom core, especially one that relies on externally defined/centrally managed tools? Are there known pitfalls or specific requirements in platform.txt or boards.txt (particularly around custom menus) that are crucial for FQBN resolution in this setup? Any insights or suggestions on what to check next would be greatly appreciated.


(I can provide links to my package_ExoNaut_index.json, platform.txt, and boards.txt if that would be helpful – e.g., via a GitHub Gist or repository).



Thanks in advance for any assistance!

Best regards