TwinCAT coding agent for Beckhoff PLC development, with strict rules for Structured Text, naming conventions, PLC-aware tooling, syntax checks, and safe project validation workflows.
Skill Claude CodeCodex
Use this skill when implementing advanced TwinCAT 3 (ExST) features. It covers Properties (GET/SET), Methods, initialization lifecycles (FBinit, FBreinit, FBexit), State Machine patterns, pragmas (attributes, conditional compiling, regions, message output), and PlcTaskSystemInfo access.
Skill Claude CodeCodex
Use this skill when the user asks about data types, arrays, structures (STRUCT), enumerations (ENUM), pointers (POINTER), references (REFERENCE), or dynamic memory allocation (NEW/DELETE). It also contains critical rules for memory alignment (packmode) to minimize padding bytes.
Skill Claude CodeCodex
Use this skill ALWAYS before generating or modifying the names of any variables, Function Blocks (FB), Data Types (DUT), Functions, Methods, Properties, or Interfaces. It contains the mandatory Beckhoff Hungarian notation rules, prefixes (b, n, f, st, fb, etc.), and shading/name resolution rules to avoid conflicts.
Skill Claude CodeCodex
Use this skill to correctly format ST (Structured Text) logic, operators, and control flow statements. It includes precedence rules, IF/CASE/FOR/WHILE loops syntax, mathematical/bitwise operator rules (MOD, SHL, ADR, BITADR), and the list of reserved IEC keywords.
Skill Claude CodeCodex
Use this skill ONLY when the user reports a build error, a compilation warning, or when CheckPlcSyntaxAsync fails. It contains specific fixes for TwinCAT IL Errors (4200-4213) and explanations for standard Compiler Warnings (1502-1990).