diff --git a/README.md b/README.md
index 884bfc8..97543df 100644
--- a/README.md
+++ b/README.md
@@ -8,7 +8,7 @@ source of truth: a file removed means its emoji is deleted.
 ## Install
 
 ```
-dpy_appemojis @ git+ssh://git@git.rethinkstudios.io/rethink-public/dpy_appemojis.git@v0.1.0
+dpy_appemojis @ git+ssh://git@git.rethinkstudios.io/rethink-public/dpy_appemojis.git@v0.1.2
 ```
 
 ## Usage
@@ -79,10 +79,19 @@ swallowed:
 - exceeding the 2000 cap raises `DPYAppEmojisError` **before** any create
 - a discord API error (`HTTPException`, which covers `Forbidden`) propagates **unwrapped** so
   a partial sync never hides behind a silent success
+- `MissingApplicationID` (raised if `refresh()` runs before the client's `application_id` is
+  set, e.g. before `on_ready`) also propagates **unwrapped** — it is a `ClientException`, not
+  an `HTTPException`, so it is never caught by an `except discord.HTTPException` clause
 
 `emoji(name)` / `get.<name>` for a name that wasn't synced raise `KeyError` / `AttributeError`
 (call `refresh()` first).
 
+## Async stance
+
+`refresh()` offloads its blocking filesystem work (folder scan, magic-byte sniff, per-file
+image read) to a worker thread via `asyncio.to_thread`, so the event loop stays responsive
+during a large sync. Only the discord API calls run on the loop directly.
+
 ## Versioning
 
 Tagged `vX.Y.Z`; pin a tag in your install line. Targets `discord.py>=2.5` (not
diff --git a/pyproject.toml b/pyproject.toml
index 7f99d9c..3b73aac 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -4,7 +4,7 @@ build-backend = "hatchling.build"
 
 [project]
 name = "dpy_appemojis"
-version = "0.1.1"
+version = "0.1.2"
 description = "Mirror a project folder onto the bot's application emojis for discord.py — folder is the source of truth. Config-free, injectable, installable."
 requires-python = ">=3.10"
 dependencies = [
diff --git a/src/dpy_appemojis/__init__.py b/src/dpy_appemojis/__init__.py
index 5ba9404..df2906f 100644
--- a/src/dpy_appemojis/__init__.py
+++ b/src/dpy_appemojis/__init__.py
@@ -12,7 +12,7 @@ from .dpy_appemojis import (
     RefreshResult,
 )
 
-__version__ = "0.1.1"
+__version__ = "0.1.2"
 
 __all__ = [
     "DPYAppEmojis",
diff --git a/src/dpy_appemojis/dpy_appemojis.py b/src/dpy_appemojis/dpy_appemojis.py
index 5067be3..b59d394 100644
--- a/src/dpy_appemojis/dpy_appemojis.py
+++ b/src/dpy_appemojis/dpy_appemojis.py
@@ -55,12 +55,19 @@ whose bytes aren't a recognized image (corrupt/truncated/mismatched extension) r
 silently syncing one and dropping the other. a missing ``assets/emojis`` folder raises
 :class:`DPYAppEmojisError` naming the path (see above) rather than mirroring an empty set.
 exceeding the app emoji cap raises before any create. discord API errors (``HTTPException``,
-which covers ``Forbidden``) propagate UNWRAPPED — a partial sync never hides behind a silent
-success. :meth:`emoji` / ``get.<name>`` for an unsynced name raise ``KeyError`` /
-``AttributeError``.
+which covers ``Forbidden``, and ``MissingApplicationID`` if the client's application_id
+isn't set yet) propagate UNWRAPPED — a partial sync never hides behind a silent success.
+:meth:`emoji` / ``get.<name>`` for an unsynced name raise ``KeyError`` / ``AttributeError``.
+
+async stance
+------------
+:meth:`refresh` offloads its blocking filesystem work (folder scan, per-file magic-byte
+sniff, per-file image read) to a thread via ``asyncio.to_thread`` so the event loop stays
+responsive during a large sync; only the discord API calls run on the loop directly.
 """
 from __future__ import annotations
 
+import asyncio
 import logging
 import os
 import re
@@ -78,6 +85,12 @@ MAX_APP_EMOJIS = 2000
 _NAME_RE = re.compile(r"^[A-Za-z0-9_]{2,32}$")
 
 
+def _read_file(path: str) -> bytes:
+    """read a file's full bytes; run off-loop via asyncio.to_thread"""
+    with open(path, "rb") as fh:
+        return fh.read()
+
+
 def _looks_like_image(header: bytes) -> bool:
     """mirror discord.py's own magic-byte sniff (png/jpeg/gif/webp) so a bad file is caught
     here, with the offending path, instead of as an anonymous ValueError from create"""
@@ -141,9 +154,11 @@ class DPYAppEmojis:
                 image format
             discord.HTTPException: any discord API error (includes Forbidden), propagated
                 unwrapped
+            discord.MissingApplicationID: the client's application_id is not set yet (e.g.
+                refresh() called before login completes), propagated unwrapped
         """
         existing = {emoji.name: emoji for emoji in await self._client.fetch_application_emojis()}
-        desired = self._scan_folder()
+        desired = await asyncio.to_thread(self._scan_folder)
 
         result = RefreshResult()
         current = dict(existing)
@@ -156,8 +171,7 @@ class DPYAppEmojis:
             )
 
         for name in to_create:
-            with open(desired[name], "rb") as fh:
-                image = fh.read()
+            image = await asyncio.to_thread(_read_file, desired[name])
             try:
                 emoji = await self._client.create_application_emoji(name=name, image=image)
             except discord.HTTPException: