Use CodeGraph to navigate MOOSE and avoid reinventing functionality it already has (MOOSE's "use existing functionality, don't reimplement it" rule - AGENTS.md, Simplicity First). Use this whenever writing or changing MOOSE C++/Python - before adding a new function, class, material, kernel, action, or utility - to check whether MOOSE, libMesh, MetaPhysicL, or MathUtils already provides it; to find the call sites and blast radius of a change; or to compare a new object against an existing sibling. CodeGraph is preferred but optional here: if the index is absent, fall back to grep/Read and suggest setting it up rather than blocking.
Review a MOOSE pull request or local branch against MOOSE's contribution standards: the MOOSE Code Standard (SCS), the SQA testing rules (every test is a requirement, with requirement/design/issues), required documentation stub pages for new objects, and PR governance (issue references, scope, required-vs-suggested phrasing). Use this whenever someone wants to review MOOSE changes or asks "review this PR", "review my branch", "is this ready to merge", "check my changes before I submit", or wants pre-submission feedback on code in the MOOSE framework or its modules - even if they never say the word "review". This is the MOOSE-aware review layer; it complements the generic /code-review and /security-review skills and defers to them for deep correctness and security analysis rather than duplicating that work.