diff --git a/insto/repl.py b/insto/repl.py
index d0aab99..1259010 100644
--- a/insto/repl.py
+++ b/insto/repl.py
@@ -45,7 +45,7 @@
 from insto.config import Config, cli_history_path, load_config
 from insto.exceptions import BackendError
 from insto.ui.banner import render_welcome
-from insto.ui.theme import get_palette, get_theme, list_themes
+from insto.ui.theme import get_palette, get_theme, list_themes, theme_description
 
 if TYPE_CHECKING:
     from prompt_toolkit.key_binding import KeyPressEvent
@@ -95,6 +95,11 @@ def _first_positional_choices(spec: Any) -> tuple[str, ...]:
     return ()
 
 
+def _theme_label(name: str) -> FormattedText:
+    """Theme name rendered in its own accent colour (for completion display)."""
+    return FormattedText([(f"fg:{get_palette(name).accent}", name)])
+
+
 class _SlashCommandCompleter(Completer):
     """Slack/Claude-Code-style command completer.
 
@@ -165,12 +170,13 @@ def get_completions(
 
         spec = COMMANDS.get(user_typed)
         if spec is not None:
+            is_theme = user_typed == "theme"
             for choice in _first_positional_choices(spec):
                 yield Completion(
                     text=f"{prefix} {choice}",
                     start_position=-len(prefix),
-                    display=choice,
-                    display_meta="",
+                    display=_theme_label(choice) if is_theme else choice,
+                    display_meta=theme_description(choice) if is_theme else "",
                 )
 
     def _argument_completions(self, text: str, stripped: str) -> Iterable[Completion]:
@@ -209,6 +215,7 @@ def _argument_completions(self, text: str, stripped: str) -> Iterable[Completion
                 if not choices:
                     return
                 lower = current_word.lower()
+                is_theme = cmd_name == "theme"
                 for choice in choices:
                     s = str(choice)
                     if not s.lower().startswith(lower):
@@ -216,8 +223,12 @@ def _argument_completions(self, text: str, stripped: str) -> Iterable[Completion
                     yield Completion(
                         text=s,
                         start_position=-len(current_word),
-                        display=s,
-                        display_meta=str(action.help or ""),
+                        # Themes render their name in their own accent colour
+                        # with a per-theme description, so the popup hints at
+                        # the look before you commit (full preview lives in the
+                        # bare-`/theme` picker).
+                        display=_theme_label(s) if is_theme else s,
+                        display_meta=theme_description(s) if is_theme else str(action.help or ""),
                     )
                 return
             pos_index += 1
@@ -415,7 +426,10 @@ def banner() -> ANSI:
 
         def footer() -> ANSI:
             name = themes[state["i"]]
-            return ANSI(f"\n  ↑/↓ preview · Enter apply · Esc cancel    theme: {name}")
+            return ANSI(
+                f"\n  ↑/↓ preview · Enter apply · Esc cancel    "
+                f"theme: {name} — {theme_description(name)}"
+            )
 
         kb = KeyBindings()
 
diff --git a/insto/ui/theme.py b/insto/ui/theme.py
index a896fcc..e75abb9 100644
--- a/insto/ui/theme.py
+++ b/insto/ui/theme.py
@@ -133,6 +133,23 @@ def _make_theme(p: _Palette) -> Theme:
 }
 
 
+# One-line descriptions surfaced in /theme completion and the picker. Keep a
+# key for every palette above (guarded by tests/test_theme.py).
+_DESCRIPTIONS: dict[str, str] = {
+    "aiograpi": "instagrapi violet → blue (default)",
+    "claude": "Claude Code burnt orange",
+    "instagram": "Instagram brand gradient",
+    "hacker": "matrix phosphor green on black",
+    "amber": "80s amber CRT phosphor",
+    "cyberpunk": "neon cyan → magenta → green",
+}
+
+
+def theme_description(name: str | None) -> str:
+    """One-line description of a theme (for /theme completion + picker footer)."""
+    return _DESCRIPTIONS.get(name or DEFAULT_THEME_NAME, "")
+
+
 THEMES: dict[str, Theme] = {name: _make_theme(p) for name, p in _PALETTES.items()}
 
 DEFAULT_THEME_NAME: str = "aiograpi"
diff --git a/tests/test_repl_completer.py b/tests/test_repl_completer.py
index a0d02fb..e80c068 100644
--- a/tests/test_repl_completer.py
+++ b/tests/test_repl_completer.py
@@ -393,3 +393,16 @@ async def runner() -> None:
     asyncio.run(runner())
     out = _console.export_text(styles=False)
     assert "unknown command" in out
+
+
+def test_theme_arg_completions_have_per_theme_meta() -> None:
+    # `/theme <Tab>` shows each theme with its OWN description (not one generic
+    # argparse-help line repeated for every choice).
+    completer = _completer()
+    doc = Document(text="/theme ", cursor_position=len("/theme "))
+    comps = list(completer.get_completions(doc, complete_event=None))  # type: ignore[arg-type]
+    metas = {c.text: c.display_meta_text for c in comps}
+    assert "hacker" in metas
+    assert "green" in metas["hacker"].lower()
+    # descriptions differ across themes
+    assert len({m for m in metas.values() if m}) > 1
diff --git a/tests/test_theme.py b/tests/test_theme.py
index c57628c..dade143 100644
--- a/tests/test_theme.py
+++ b/tests/test_theme.py
@@ -14,6 +14,7 @@
     get_theme,
     is_known,
     list_themes,
+    theme_description,
 )
 
 # Style keys every theme must resolve (mirrors `_make_theme`).
@@ -65,3 +66,17 @@ def test_unknown_theme_falls_back_to_default() -> None:
     assert get_theme("nope") is THEMES[DEFAULT_THEME_NAME]
     assert get_palette(None) is get_palette(DEFAULT_THEME_NAME)
     assert not is_known("nope")
+
+
+def test_every_theme_has_a_description() -> None:
+    seen = set()
+    for name in list_themes():
+        desc = theme_description(name)
+        assert desc, f"theme {name!r} has no description"
+        seen.add(desc)
+    # descriptions are distinct (not the same generic line for all)
+    assert len(seen) == len(list_themes())
+
+
+def test_theme_description_hacker() -> None:
+    assert "green" in theme_description("hacker").lower()