Module command 

Typed command IR and governance tiers (PSP-8 System 8).

sh -c is not an implicit compatibility path. A command proposal is parsed into a typed CommandInvocation; verifier commands prefer the Program form, and the Shell form requires a capability that explicitly names shell execution. Coreutils, awk, and sed are modeled in three tiers so that a read-only inspection cannot silently become a workspace mutation.

Enums

CommandInvocation

A canonicalized command invocation.

CommandTier

Governance tier for coreutils / awk / sed style commands (PSP-8 System 8).

Functions

canonicalize

Canonicalize a raw command string. A command free of shell composition is parsed into the Program form; otherwise it is a Shell invocation that requires a shell capability. Parsing is intentionally simple and shell-free: quoting is parsed as argv syntax, while composition operators still force the Shell form. Invalid argv syntax also fails closed to the shell form and therefore requires explicit shell authority.

classify_tier

Classify a program invocation into a governance tier. This is a conservative default: anything not recognized as read-only is treated as a mutation so a novel tool cannot slip through as inspection.

has_shell_composition

Whether a raw command string contains shell composition.