diff --git a/vcsserver/base.py b/vcsserver/base.py
--- a/vcsserver/base.py
+++ b/vcsserver/base.py
@@ -137,7 +137,7 @@ def archive_repo(walker, archive_dest_pa
 
 
 class BinaryEnvelope(object):
-    def __init__(self, value, bin_type=True):
+    def __init__(self, value: bytes, bin_type=True):
         self.value = value
         self.bin_type = bin_type
 
diff --git a/vcsserver/hgcompat.py b/vcsserver/hgcompat.py
--- a/vcsserver/hgcompat.py
+++ b/vcsserver/hgcompat.py
@@ -72,7 +72,8 @@ from mercurial import strip as hgext_str
 
 
 def get_ctx(repo, ref):
-    ref = safe_bytes(ref)
+    if not isinstance(ref, int):
+        ref = safe_bytes(ref)
     try:
         ctx = repo[ref]
     except (ProgrammingError, TypeError):
diff --git a/vcsserver/http_main.py b/vcsserver/http_main.py
--- a/vcsserver/http_main.py
+++ b/vcsserver/http_main.py
@@ -507,6 +507,7 @@ class HTTPApplication(object):
             bin_type = False
             res = value.get('result')
             if res and isinstance(res, BinaryEnvelope):
+                log.debug('Result is wrapped in BinaryEnvelope type')
                 value['result'] = res.value
                 bin_type = res.bin_type
 
@@ -516,6 +517,8 @@ class HTTPApplication(object):
                 ct = response.content_type
                 if ct == response.default_content_type:
                     response.content_type = 'application/x-msgpack'
+                    if bin_type:
+                        response.content_type = 'application/x-msgpack-bin'
 
             return msgpack.packb(value, use_bin_type=bin_type)
         return _render