diff --git a/.github/workflows/workstation-scripts.yml b/.github/workflows/workstation-scripts.yml
index 2f3969d..7cdf80a 100644
--- a/.github/workflows/workstation-scripts.yml
+++ b/.github/workflows/workstation-scripts.yml
@@ -57,7 +57,7 @@ jobs:
             bash -n "$f"
           done <<<"$files"
 
-      - name: Smoke: patch-shell idempotent
+      - name: Smoke: patch-shell apply is idempotent
         run: |
           set -euo pipefail
           p='profiles/linux-dev/workstation-v0/bin/patch-shell.sh'
@@ -73,6 +73,34 @@ jobs:
           test "$(grep -cF '# <<< sourceos workstation-v0 <<<' "$tmp")" -eq 1
           grep -F 'export PATH="$HOME/.local/bin:$PATH"' "$tmp" >/dev/null
 
+      - name: Smoke: patch-shell revert removes marker block
+        run: |
+          set -euo pipefail
+          p='profiles/linux-dev/workstation-v0/bin/patch-shell.sh'
+          tmp=$(mktemp)
+          printf '# rc\n' > "$tmp"
+
+          SOURCEOS_RC_FILES="$tmp" bash "$p" apply
+          SOURCEOS_RC_FILES="$tmp" bash "$p" revert
+
+          ! grep -qF '# >>> sourceos workstation-v0 >>>' "$tmp"
+          ! grep -qF '# <<< sourceos workstation-v0 <<<' "$tmp"
+
+      - name: Smoke: patch-fish apply/revert
+        run: |
+          set -euo pipefail
+          p='profiles/linux-dev/workstation-v0/bin/patch-fish.sh'
+          bash -n "$p"
+
+          tmp=$(mktemp)
+          printf '# fish\n' > "$tmp"
+
+          SOURCEOS_FISH_CONFIG="$tmp" bash "$p" apply
+          SOURCEOS_FISH_CONFIG="$tmp" bash "$p" revert
+
+          ! grep -qF '# >>> sourceos workstation-v0 (fish) >>>' "$tmp"
+          ! grep -qF '# <<< sourceos workstation-v0 (fish) <<<' "$tmp"
+
       - name: Smoke: sourceos help exits cleanly
         run: |
           set -euo pipefail
diff --git a/docs/workstation/RUNBOOK.md b/docs/workstation/RUNBOOK.md
index b0ba126..0cfa033 100644
--- a/docs/workstation/RUNBOOK.md
+++ b/docs/workstation/RUNBOOK.md
@@ -64,18 +64,20 @@ Run:
 SOURCEOS_AUTOPATCH_SHELL=1 ./profiles/linux-dev/workstation-v0/install.sh
 ```
 
-Or via the palette:
+Bash/Zsh helper:
 
 ```bash
-sourceos fix shell dry-run
-sourceos fix shell apply
+./profiles/linux-dev/workstation-v0/bin/patch-shell.sh dry-run
+./profiles/linux-dev/workstation-v0/bin/patch-shell.sh apply
+./profiles/linux-dev/workstation-v0/bin/patch-shell.sh revert
 ```
 
-For fish:
+Fish helper:
 
 ```bash
 ./profiles/linux-dev/workstation-v0/bin/patch-fish.sh dry-run
 ./profiles/linux-dev/workstation-v0/bin/patch-fish.sh apply
+./profiles/linux-dev/workstation-v0/bin/patch-fish.sh revert
 ```
 
 ---
diff --git a/profiles/linux-dev/workstation-v0/bin/patch-fish.sh b/profiles/linux-dev/workstation-v0/bin/patch-fish.sh
index 4835a2d..fc750c2 100644
--- a/profiles/linux-dev/workstation-v0/bin/patch-fish.sh
+++ b/profiles/linux-dev/workstation-v0/bin/patch-fish.sh
@@ -3,8 +3,15 @@ set -euo pipefail
 
 # Patch fish config to source SourceOS fish spine.
 # Idempotent marker block.
+# Modes:
+# - apply (default)
+# - dry-run
+# - revert (remove the marker block)
+#
+# CI/test hook:
+# - SOURCEOS_FISH_CONFIG may override the fish config path.
 
-MODE="${1:-apply}"  # apply|dry-run
+MODE="${1:-apply}"  # apply|dry-run|revert
 
 info(){ printf "INFO: %s\n" "$*" >&2; }
 warn(){ printf "WARN: %s\n" "$*" >&2; }
@@ -14,7 +21,11 @@ marker_start="# >>> sourceos workstation-v0 (fish) >>>"
 marker_end="# <<< sourceos workstation-v0 (fish) <<<"
 
 fish_cfg(){
-  echo "${XDG_CONFIG_HOME:-$HOME/.config}/fish/config.fish"
+  if [[ -n "${SOURCEOS_FISH_CONFIG:-}" ]]; then
+    printf '%s\n' "$SOURCEOS_FISH_CONFIG"
+  else
+    printf '%s\n' "${XDG_CONFIG_HOME:-$HOME/.config}/fish/config.fish"
+  fi
 }
 
 has_block(){
@@ -23,20 +34,19 @@ has_block(){
 }
 
 block(){
-  cat <<'EOF'
-# >>> sourceos workstation-v0 (fish) >>>
+  cat <<EOF
+${marker_start}
 # Added by SourceOS Workstation v0
-set spine_path "${XDG_CONFIG_HOME:-$HOME/.config}/sourceos/shell/common.fish"
-if test -f "$spine_path"
-  source "$spine_path"
+set spine_path "\${XDG_CONFIG_HOME:-\$HOME/.config}/sourceos/shell/common.fish"
+if test -f "\$spine_path"
+  source "\$spine_path"
 end
-# <<< sourceos workstation-v0 (fish) <<<
+${marker_end}
 EOF
 }
 
-apply(){
-  local f
-  f="$(fish_cfg)"
+apply_to_file(){
+  local f=$1
 
   if [[ ! -e "$f" ]]; then
     warn "fish config not found (skipping): $f"
@@ -62,16 +72,56 @@ apply(){
   info "patched: $f"
 }
 
+revert_from_file(){
+  local f=$1
+
+  if [[ ! -e "$f" ]]; then
+    warn "fish config not found (skipping): $f"
+    return 0
+  fi
+
+  if ! has_block "$f"; then
+    info "no patch block present: $f"
+    return 0
+  fi
+
+  if [[ "$MODE" == "dry-run" ]]; then
+    info "would revert: $f"
+    return 0
+  fi
+
+  local tmp
+  tmp="$(mktemp)"
+
+  awk -v s="$marker_start" -v e="$marker_end" '
+    $0 == s {skip=1; next}
+    $0 == e {skip=0; next}
+    skip {next}
+    {print}
+  ' "$f" > "$tmp"
+
+  mv "$tmp" "$f"
+  info "reverted: $f"
+}
+
 main(){
   case "$MODE" in
-    apply|dry-run) ;;
+    apply|dry-run|revert) ;;
     *)
-      err "unknown mode: $MODE (use apply|dry-run)"
+      err "unknown mode: $MODE (use apply|dry-run|revert)"
       exit 2
       ;;
   esac
 
-  apply
+  local f
+  f="$(fish_cfg)"
+
+  if [[ "$MODE" == "revert" ]]; then
+    revert_from_file "$f"
+  else
+    apply_to_file "$f"
+  fi
+
   info "done"
 }
 
diff --git a/profiles/linux-dev/workstation-v0/bin/patch-shell.sh b/profiles/linux-dev/workstation-v0/bin/patch-shell.sh
index 2f15248..db07448 100644
--- a/profiles/linux-dev/workstation-v0/bin/patch-shell.sh
+++ b/profiles/linux-dev/workstation-v0/bin/patch-shell.sh
@@ -6,9 +6,15 @@ set -euo pipefail
 # - source the SourceOS shell spine (`$XDG_CONFIG_HOME/sourceos/shell/common.sh`)
 #
 # Idempotent: uses a marker block.
-# CI/test hook: SOURCEOS_RC_FILES may be set to a colon-separated list of rc files.
+# Modes:
+# - apply (default)
+# - dry-run (for apply)
+# - revert (remove the marker block)
+#
+# CI/test hook:
+# - SOURCEOS_RC_FILES may be set to a colon-separated list of rc files.
 
-MODE="${1:-apply}"  # apply|dry-run
+MODE="${1:-apply}"  # apply|dry-run|revert
 
 info(){ printf "INFO: %s\n" "$*" >&2; }
 warn(){ printf "WARN: %s\n" "$*" >&2; }
@@ -77,17 +83,48 @@ apply_to_file() {
   info "patched: $f"
 }
 
+revert_from_file() {
+  local f=$1
+
+  if [[ ! -e "$f" ]]; then
+    warn "rc file not found (skipping): $f"
+    return 0
+  fi
+
+  if ! has_block "$f"; then
+    info "no patch block present: $f"
+    return 0
+  fi
+
+  local tmp
+  tmp="$(mktemp)"
+
+  awk -v s="$marker_start" -v e="$marker_end" '
+    $0 == s {skip=1; next}
+    $0 == e {skip=0; next}
+    skip {next}
+    {print}
+  ' "$f" > "$tmp"
+
+  mv "$tmp" "$f"
+  info "reverted: $f"
+}
+
 main(){
   case "$MODE" in
-    apply|dry-run) ;;
+    apply|dry-run|revert) ;;
     *)
-      err "unknown mode: $MODE (use apply|dry-run)"
+      err "unknown mode: $MODE (use apply|dry-run|revert)"
       exit 2
       ;;
   esac
 
   while IFS= read -r rc; do
-    apply_to_file "$rc"
+    if [[ "$MODE" == "revert" ]]; then
+      revert_from_file "$rc"
+    else
+      apply_to_file "$rc"
+    fi
   done < <(rc_candidates)
 
   info "done"