Add "checkout_clang_tidy": True to .gclient file in the custom_vars (or use standalone-maximal.gclient which includes this).
"custom_vars": { "checkout_clang_tidy": True, }
gclient sync
Set up a build directory for the configuration you want to run. It doesn't need to be built yet. This can be a native build or a cross-compiled build.
Run tools/run-tricium-clang-tidy.py --help for instructions. Running the tool with --default takes about 12 minutes on a 10-core M1 Pro laptop and under 2.5 minutes on a 64-core (128-thread) cloud VM.
This will output out/*/clang-tidy-*-findings.json with the full findings, and out/*/clang-tidy-*-summary.txt with a nicely-formatted list of results.
Once you have findings, you can automatically apply fixes across any set of files for a specific check (if it supports autofix): Run tools/apply-clang-tidy-fixes.py --help for instructions.
Tips:
It's recommended to set up clangd and open a file in your IDE to see the errors in context (and to get an autofix button). Note the FastCheckFilter option mentioned there.
In VSCode you can less the summary file to your terminal and then cmd-click/ctrl-click the lines to take you to the exact source line.
For additional info on running Clang-Tidy locally, see these instructions.