diff --git a/dot_functions b/dot_functions
index 0f2f5db332..63f9fd7c71 100644
--- a/dot_functions
+++ b/dot_functions
@@ -2231,6 +2231,19 @@ function git-doctor() {
 	print -r -- "configs: $(command git config --list --show-origin --name-only 2>/dev/null | command awk -F'\t' '$1 ~ /^file:/ {print substr($1, 6)}' | command awk '!seen[$0]++' | command paste -sd, - | command sed 's/,/, /g')";
 }
 
+# Set this tab's row in iTerm2's Session Status panel:
+#   tabstatus <status> [detail] [--dot-color '#rrggbb' --text-color …]
+# `tabstatus` alone clears it. Goes through `it2 set-status` (the API), not the
+# OSC 21337 escape, because the escape needs the tab's tty and neither Claude
+# Code's Bash tool nor its hooks have one. iTerm2's own cc-status hook rewrites
+# the row on the next Claude Code event, so inside a session this lasts a turn.
+function tabstatus() {
+	[[ -n $ITERM_SESSION_ID ]] || { print -ru2 -- "tabstatus: not inside an iTerm2 session"; return 1; }
+	local st=${1-} detail=${2-};
+	(( $# )) && shift; (( $# )) && shift;
+	command it2 set-status --session "${ITERM_SESSION_ID#*:}" --status "$st" --detail "$detail" "$@" >/dev/null;
+}
+
 # Where iTerm2 is installed, or nothing. $ITERM2_APP names a non-standard
 # location and, when set, is used *exclusively* — an override that quietly
 # fell back to /Applications would make every answer below a lie about a
diff --git a/tests/tabstatus.bats b/tests/tabstatus.bats
new file mode 100644
index 0000000000..0e6b5288e3
--- /dev/null
+++ b/tests/tabstatus.bats
@@ -0,0 +1,32 @@
+#!/usr/bin/env bats
+
+# tabstatus in dot_functions fills in the session id `it2 set-status` demands.
+# it2 is stubbed to record its argv; no test touches a real iTerm2.
+
+setup() {
+  STUB="$BATS_TEST_TMPDIR/bin"
+  mkdir -p "$STUB"
+  printf '#!/bin/sh\nprintf "%%s\\n" "$@" > "%s/argv"\n' "$BATS_TEST_TMPDIR" > "$STUB/it2"
+  chmod +x "$STUB/it2"
+  PATH="$STUB:$PATH"
+  DOTFUNCTIONS="$BATS_TEST_DIRNAME/../dot_functions"
+}
+
+@test "tabstatus: passes the session uuid, status, detail and extra flags" {
+  run zsh -c "ITERM_SESSION_ID=w0t1p0:ABC-123; source '$DOTFUNCTIONS'; tabstatus 'reviewing PR' 'on CI' --dot-color '#66cccc'"
+  [ "$status" -eq 0 ]
+  [ "$(paste -sd'|' "$BATS_TEST_TMPDIR/argv")" = "set-status|--session|ABC-123|--status|reviewing PR|--detail|on CI|--dot-color|#66cccc" ]
+}
+
+@test "tabstatus: no arguments clears status and detail" {
+  run zsh -c "ITERM_SESSION_ID=w0t1p0:ABC-123; source '$DOTFUNCTIONS'; tabstatus"
+  [ "$status" -eq 0 ]
+  [ "$(paste -sd'|' "$BATS_TEST_TMPDIR/argv")" = "set-status|--session|ABC-123|--status||--detail|" ]
+}
+
+@test "tabstatus: outside iTerm2 is an error and never calls it2" {
+  run zsh -c "unset ITERM_SESSION_ID; source '$DOTFUNCTIONS'; tabstatus working"
+  [ "$status" -eq 1 ]
+  [[ "$output" == *"not inside an iTerm2 session"* ]]
+  [ ! -e "$BATS_TEST_TMPDIR/argv" ]
+}