1 files changed, 35 insertions, 37 deletions
diff --git a/tools/fs_patch.sh b/tools/fs_patch.sh
index a87cef5..060c99a 100755
--- a/tools/fs_patch.sh
+++ b/tools/fs_patch.sh
@@ -2,12 +2,13 @@
 set -uo pipefail
 
 # @describe Apply a patch to a file at the specified path.
-# NOTE: This tool NEVER exits with non-zero (even on missing args). It reports errors in output.
-# @option --path The path of the file to apply to
-# @option --contents The patch to apply to the file
-# @env LLM_OUTPUT=/dev/stdout The output path
+# This can be used to edit the file, without having to rewrite the whole file.
+# This tool NEVER requests user interaction and NEVER exits with a non-zero code.
+# Any error is reported in the tool output so the model can react within the same cycle.
+# @option --path! The path of the file to apply to
+# @option --contents! The patch to apply to the file
 #
-# Example:
+# Here is an example of a patch block that can be applied to modify the file to request the user's name:
 # --- a/hello.py
 # +++ b/hello.py
 # \@@ ... @@
@@ -16,9 +17,12 @@ set -uo pipefail
 # +    name = input("What is your name? ")
 # +    print(f"Hello {name}")
 
+# @env LLM_OUTPUT=/dev/stdout The output path
+
 ROOT_DIR="${LLM_ROOT_DIR:-$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)}"
 OUT="${LLM_OUTPUT:-/dev/stdout}"
 
+# Report an error in the tool output and finish successfully (exit 0).
 err() {
   echo "ERROR: $*" >> "$OUT"
   exit 0
@@ -28,47 +32,41 @@ main() {
   path="${argc_path:-}"
   patch="${argc_contents:-}"
 
-  [[ -z "${path}" ]]  && err "missing --path"
-  [[ -z "${patch}" ]] && err "missing --contents"
-  [[ ! -e "${path}" ]] && err "file not found: ${path}"
-  [[ ! -f "${path}" ]] && err "not a regular file: ${path}"
-  [[ ! -r "${path}" ]] && err "file not readable: ${path}"
+  [[ -z "$path" ]]  && err "missing --path"
+  [[ -z "$patch" ]] && err "missing --contents"
+  [[ ! -e "$path" ]] && err "file not found: $path"
+  [[ ! -f "$path" ]] && err "not a regular file: $path"
+  [[ ! -r "$path" ]] && err "file not readable: $path"
 
   new_contents=""
-  if ! new_contents="$(awk -f "$ROOT_DIR/utils/patch.awk" "$path" <(printf "%s" "$patch") 2>/tmp/fs_patch.err)"; then
-    msg="$(cat /tmp/fs_patch.err 2>/dev/null || true)"
-    err "patch apply failed for ${path}: ${msg:-unknown error}"
+  if ! new_contents="$(awk -f "$ROOT_DIR/utils/patch.awk" "$path" <(printf "%s" "$patch") 2>/tmp/fs_patch_new.err)"; then
+    msg="$(cat /tmp/fs_patch_new.err 2>/dev/null || true)"
+    err "patch apply failed for $path: ${msg:-unknown error}"
   fi
 
-  # Diff in Tool-Output schreiben (damit das LLM es sieht)
+  # Show the diff (if any) so the model sees what is applied.
+  # NOTE: no guard_operation.sh here -> no user interaction.
   printf "%s" "$new_contents" | git diff --no-index "$path" - >> "$OUT" 2>/dev/null || true
 
-  # Guard kann “abbrechen” -> als ERROR ausgeben, aber exit 0
-  if ! "$ROOT_DIR/utils/guard_operation.sh" "Apply changes?" >>"$OUT" 2>&1; then
-    err "operation cancelled by user"
-  fi
-
-  if ! printf "%s" "$new_contents" > "$path" 2>/tmp/fs_patch_write.err; then
-    msg="$(cat /tmp/fs_patch_write.err 2>/dev/null || true)"
-    err "failed to write patched file ${path}: ${msg:-unknown error}"
+  if ! printf "%s" "$new_contents" > "$path" 2>/tmp/fs_patch_new_write.err; then
+    msg="$(cat /tmp/fs_patch_new_write.err 2>/dev/null || true)"
+    err "failed to write patched file $path: ${msg:-unknown error}"
   fi
 
-  echo "The patch applied to: ${path}" >> "$OUT"
+  echo "The patch applied to: $path" >> "$OUT"
   exit 0
 }
 
-# IMPORTANT: Do not let argc failures abort the script.
-# - remove "set -e"
-# - and swallow argc's non-zero return
-eval "$(argc --argc-eval "$0" "$@" 2>/tmp/argc_fs_patch.err || true)"
-
-# If argc itself failed (e.g. parse error), report but still exit 0
-if [[ -s /tmp/argc_fs_patch.err ]]; then
-  echo "ERROR: argc parse failed: $(cat /tmp/argc_fs_patch.err)" >> "$OUT"
-  rm -f /tmp/argc_fs_patch.err
-  exit 0
+# Parse arguments with argc and run the tool in a subshell:
+# - argc calls `main`, which always ends with `exit 0`.
+# - If argc itself fails (missing/invalid arguments) its generated code prints the
+#   error to stderr and calls `exit 1`; running it in a subshell keeps that from
+#   terminating this script, and the message is captured into the tool output.
+# - The script itself always finishes with exit 0.
+argc_err="$(mktemp)"
+( eval "$(argc --argc-eval "$0" "$@" 2>/dev/null)" ) 2>"$argc_err"
+if [[ -s "$argc_err" ]]; then
+  { echo "ERROR: argument parsing failed:"; cat "$argc_err"; } >> "$OUT"
 fi
-rm -f /tmp/argc_fs_patch.err
-
-main
-
+rm -f "$argc_err"
+exit 0