Module install 

Merging the steering hook into a Claude Code settings file. The merge runs through the comment- and layout-preserving ct-patch engine (crate::patch): the existing file is parsed only to decide which edits to make, and those edits are byte-range splices against the original text, so the user’s comments and formatting survive.

Enums

Scope

Which settings file the hook is written to.

Tool

A harness tool the steering hook can be installed to gate. Each becomes its own PreToolUse matcher entry; Bash is the default.

Functions

hook_command

The PreToolUse hook command written into settings, built on head — the invocation prefix, "ct steer hook" by default or a pinned "<abs-path> hook" (see --pin). Tool-call logging is on by default (to .ct/tclog/), so the bare command already logs; no_log/log_dir bake in the logging override, and nudge_pipelines bakes in --nudge-pipelines.

install

Install the steering hook into existing settings text (or create a fresh document), gating each tool in tools. Returns the new text and whether it changed. Idempotent: re-installing the same command/tools is a no-op; a --mode change rewrites the command in place; a new tool adds its matcher. Comments and layout in existing are preserved.

install_post

Install the PostToolUse recorder (--measure) as a single * matcher running command, so every executed call is logged for effectiveness analysis. Idempotent, comment-preserving, and independent of the PreToolUse steering hook.

post_command

The PostToolUse command written into settings by --measure (records each executed call), built on head ("ct steer post" or a pinned form).

uninstall

Remove every steering hook (PreToolUse steer and PostToolUse recorder) from existing settings text, pruning emptied matcher entries and the hooks containers when they end up empty. Comments and layout elsewhere are preserved.