diff --git a/MANIFEST.in b/MANIFEST.in
index 44d5cc7618..c24786c3b3 100644
--- a/MANIFEST.in
+++ b/MANIFEST.in
@@ -8,6 +8,7 @@ include demo/demo.tls.dh
 include demo/*.py
 include demo/*.sh
 
+include synapse/py.typed
 recursive-include synapse/storage *.sql
 recursive-include synapse/storage *.sql.postgres
 recursive-include synapse/storage *.sql.sqlite
diff --git a/changelog.d/11054.misc b/changelog.d/11054.misc
new file mode 100644
index 0000000000..1103368fec
--- /dev/null
+++ b/changelog.d/11054.misc
@@ -0,0 +1 @@
+Mark the Synapse package as containing type annotations and fix export declarations so that Synapse pluggable modules may be type checked against Synapse.
diff --git a/synapse/module_api/errors.py b/synapse/module_api/errors.py
index 98ea911a81..1db900e41f 100644
--- a/synapse/module_api/errors.py
+++ b/synapse/module_api/errors.py
@@ -14,9 +14,16 @@
 
 """Exception types which are exposed as part of the stable module API"""
 
-from synapse.api.errors import (  # noqa: F401
+from synapse.api.errors import (
     InvalidClientCredentialsError,
     RedirectException,
     SynapseError,
 )
-from synapse.config._base import ConfigError  # noqa: F401
+from synapse.config._base import ConfigError
+
+__all__ = [
+    "InvalidClientCredentialsError",
+    "RedirectException",
+    "SynapseError",
+    "ConfigError",
+]
diff --git a/synapse/py.typed b/synapse/py.typed
new file mode 100644
index 0000000000..e69de29bb2