Systematic debugging guide for Pharo Smalltalk development. Provides expertise in error diagnosis (MessageNotUnderstood, KeyNotFound, SubscriptOutOfBounds, AssertionFailure), incremental code execution with eval tool, intermediate value inspection, error handling patterns (on:do: blocks), stack trace analysis, UI debugger window detection (read_screen for hung operations), Transcript logging (crShow:, ##DEBUG## prefix, format strings, call-site tracing with thisContext, headless output via NonInteractiveTranscript), and debug-fix-reimport workflow. Use when encountering Pharo test failures, Smalltalk exceptions, unexpected behavior, timeout or non-responsive operations, need to verify intermediate values, execute code incrementally for diagnosis, troubleshoot Tonel import errors, add debug logging to trace variable values or call sites, or redirect Transcript output in headless/Docker images.
How to install smalltalk-debugger?
mumez/smalltalk-dev-plugin/smalltalk-debugger
$npx -y skills add mumez/smalltalk-dev-plugin --skill smalltalk-debuggerInstalls into the current project.
›Prefer a prompt? Paste this to your agent
Run `npx skills use "https://github.com/mumez/smalltalk-dev-plugin" --skill "mumez/smalltalk-dev-plugin/smalltalk-debugger"` and follow the generated skill instructions now. Read its complete output, redirecting it to a temporary file first if necessary. Resolve relative paths from the supporting-files directory it provides.
Use the skills in "https://github.com/mumez/smalltalk-dev-plugin" that are relevant to the current task. Run `npx skills add "https://github.com/mumez/smalltalk-dev-plugin"` and select the relevant skills, then follow their instructions.
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