Debugging
Finding and fixing the cause of a defect, crash or failing build.
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- Debug a failing network request
Diagnoses a failing HTTP request layer by layer (DNS, TLS, proxy, CORS, auth, timeouts, payload) from error output and curl or browser traces, giving the next command at each step.
- Debug a production-only bug
Debugs a bug that happens only in production by diffing environment, config, data, traffic, versions and timing, then plans safe instrumentation to confirm the cause. Use for works-on-my-machine bugs.
- Bisect a regression
Finds the commit or input that introduced a regression by writing an automated good/bad check first, then bisecting. Use when something that used to work is broken and the cause is unclear.
- Bugfix track
Takes a bug from report to reproduction, root cause, regression test, minimal fix and a verified pull request, stopping for approval between steps. Use for any bug worth fixing properly.
- Debug bus communication
Coaches you through failing I2C, SPI, UART or CAN communication one check at a time, from wiring and pull-ups to clock settings, addressing and logic analyser captures.
- Debug a mobile app crash
Debugs a mobile app crash from a symbolicated report, reading the crashed thread and frames to find the likely cause, a reproduction and a fix. Use when a crash shows up in the crash reporter.
- Debug a native crash
Debugs a native crash or segfault in C, C++ or Rust from core dumps, backtraces and sanitizer output, ranks the likely memory or concurrency causes and names the next command to run.
- Debug a race condition
Diagnoses intermittent concurrency bugs by mapping shared state and the interleavings that break it, adds targeted instrumentation and proposes a fix. Use for bugs seen only under load.
- Debugger
Debugs by reproducing first, testing one hypothesis at a time and fixing root causes, never symptoms. Use as a persona or subagent for bugs, crashes and failing builds.
- Decode a microcontroller hard fault
Decodes an ARM Cortex-M HardFault or similar exception from fault status registers and the stacked frame, locates the faulting instruction via the map file and names the likely cause.
- Diagnose a mobile app freeze
Diagnoses Android ANRs and iOS hangs or watchdog terminations from traces, finding main-thread blocking I/O, locks, binder calls or heavy layout, and fixes each with the right threading tool.
- Diagnose a crash-looping pod
Diagnoses a Kubernetes pod stuck in CrashLoopBackOff, ImagePullBackOff, OOMKilled or Pending from describe output, events and logs, in a fixed order of checks, with the fix for each cause.
- Explain a stack trace
Explains an error and its stack trace in plain words, finds the frame that matters, and ranks the likely causes with the next checks to run. Use when an exception or crash is hard to read.
- Find and fix latent bugs before users do
Hunts a codebase or module for latent functional bugs such as unhandled edge cases, missing guards, silent failures, races and leaks, proves each with a failing test, then fixes it.
- Find the root cause of a bug
Reproduces a bug, tests ranked hypotheses with experiments, and fixes the root cause instead of the symptom. Use when something is broken and the reason is not obvious.
- Fix a CSS layout bug
Finds the cause of a CSS layout bug such as overflow, stacking, or flex and grid misbehaviour from markup, styles and a description, then fixes it and explains why. Use for broken layouts.
- Fix a date and time bug
Fixes date and time bugs caused by time zones, daylight saving, parsing, formatting or storage, and adds tests for the edge cases that broke it. Use for off-by-one-day and off-by-one-hour bugs.
- Fix a failing Docker build
Diagnoses a failing Docker build from the Dockerfile and build log, finds the first real error among the noise and gives the smallest fix. Use when docker build or a CI image build fails.
- Fix a mobile build failure
Finds and fixes a failing Xcode, Gradle, CocoaPods, React Native or Flutter build from its log, covering dependencies, signing, toolchain versions and stale caches, with the smallest fix.
- Fix physics jitter and tunnelling
Finds why objects jitter, tunnel through walls or explode in a game physics simulation by checking update order, interpolation, timestep, continuous collision and mass ratios, then fixes the cause.
- Fix a text encoding bug
Fixes text encoding bugs such as mojibake, broken emoji, question marks or byte order marks by tracing the bytes through files, databases and APIs to the hop that breaks them. Use for garbled text.
- Solve a debugging case by experiment
Gives a failing program and a bug report, answers the learner's requests for logs, values and experiments consistently, and confirms the root cause only when they reason to it.
- Turn a bug report into a minimal reproduction
Turns a vague bug report into a minimal, reliable reproduction, preferably a failing test, and states the exact conditions needed. Use before fixing a reported bug or when triaging issues.
- Resolve a dependency conflict
Resolves a dependency conflict in npm, pip, Maven or a similar tool by tracing the resolver output to the clashing constraints and choosing the safest versions. Use when an install fails.
- Triage a failing CI build
Finds the first real error in a failing CI log, classifies the failure as caused by the change, flaky, environment drift or already broken, and names the next action. Use when a pipeline turns red.
Not: production alerts and outages (incident); flaky tests (testing).