diff --git a/mautrix_telegram/web/provisioning/__init__.py b/mautrix_telegram/web/provisioning/__init__.py
index 1c609aaf..95919c58 100644
--- a/mautrix_telegram/web/provisioning/__init__.py
+++ b/mautrix_telegram/web/provisioning/__init__.py
@@ -31,6 +31,7 @@ class ProvisioningAPI(AuthAPI):
 
         self.app = web.Application(loop=loop)
 
+        self.app.router.add_route("GET", "/{mxid:@[^:]*:.+}/get_me", self.get_me)
         login_prefix = "/login/{mxid:@[^:]*:.+}"
         self.app.router.add_route("POST", f"{login_prefix}/bot_token", self.send_bot_token)
         self.app.router.add_route("POST", f"{login_prefix}/request_code", self.request_code)
@@ -57,7 +58,7 @@ class ProvisioningAPI(AuthAPI):
             }
         return web.json_response(resp, status=status)
 
-    async def get_request_info(self, request: web.Request):
+    async def get_request_info(self, request: web.Request, get_data=True, fail_on_logged_in=True):
         auth = request.headers.get("Authorization", "")
         if auth != f"Bearer {self.secret}":
             return None, None, self.get_login_response(error="Shared secret is not valid.",
@@ -65,23 +66,41 @@ class ProvisioningAPI(AuthAPI):
                                                        status=401)
 
         data = None
-        try:
-            data = await request.json()
-        except json.JSONDecodeError:
-            pass
-        if not data:
-            return None, None, self.get_login_response(error="Invalid JSON.",
-                                                       errcode="json_invalid", status=400)
+        if get_data:
+            try:
+                data = await request.json()
+            except json.JSONDecodeError:
+                pass
+            if not data:
+                return None, None, self.get_login_response(error="Invalid JSON.",
+                                                           errcode="json_invalid", status=400)
 
         mxid = request.match_info["mxid"]
         user = await User.get_by_mxid(mxid).ensure_started(even_if_no_session=True)
         if not user.puppet_whitelisted:
             return None, user, self.get_login_response(error="You are not whitelisted.",
                                                        errcode="mxid_not_whitelisted", status=403)
-        elif await user.is_logged_in():
+        elif fail_on_logged_in and await user.is_logged_in():
             return None, user, self.get_login_response(username=user.username, status=409)
         return data, user, None
 
+    async def get_me(self, request: web.Request):
+        data, user, err = await self.get_request_info(request, get_data=False,
+                                                      fail_on_logged_in=False)
+        if err is not None:
+            return err
+        if not await user.is_logged_in():
+            return self.get_login_response(status=403, error="You are not logged in.",
+                                           errcode="not_logged_in")
+        me = await user.client.get_me()
+        return web.json_response({
+            "username": me.username,
+            "first_name": me.first_name,
+            "last_name": me.last_name,
+            "phone": me.phone,
+            "is_bot": me.bot,
+        })
+
     async def send_bot_token(self, request: web.Request):
         data, user, err = await self.get_request_info(request)
         if err is not None:
diff --git a/mautrix_telegram/web/provisioning/spec.yaml b/mautrix_telegram/web/provisioning/spec.yaml
index aa911d46..5766af2e 100644
--- a/mautrix_telegram/web/provisioning/spec.yaml
+++ b/mautrix_telegram/web/provisioning/spec.yaml
@@ -26,6 +26,51 @@ tags:
 - name: Authentication
 
 paths:
+  /{mxid}/get_me:
+    get:
+      operationId: get_me
+      summary: Get the info of the Telegram user the given Matrix user is logged in as
+      tags: [Authentication]
+      responses:
+        200:
+          description: User is logged in
+          schema:
+            $ref: "#/definitions/AuthInfo"
+        400:
+          $ref: "#/responses/MissingMXIDError"
+        403:
+          description: User is not logged in or not whitelisted
+          schema:
+            type: object
+            title: Error
+            properties:
+              errcode:
+                type: string
+                title: Error code
+                description: A machine-readable error code
+                enum:
+                - not_logged_in
+                - mxid_not_whitelisted
+              error:
+                $ref: "#/definitions/HumanReadableError"
+        500:
+          $ref: "#/responses/UnknownError"
+      parameters:
+        - name: mxid
+          in: path
+          description: The Matrix ID of the user who to log in as
+          required: true
+          type: string
+        - name: body
+          in: body
+          required: true
+          schema:
+            type: object
+            properties:
+              token:
+                type: string
+                description: The access token of the bot to log in as
+                example: "297900271:IXjeGEcAN61zHnjPgkWnYWyvVp9K4ulHBEv"
   /login/{mxid}/bot_token:
     post:
       operationId: post_bot_token
@@ -388,6 +433,25 @@ definitions:
     type: string
     description: A human-readable description of the error
     example: A human-readable description of the error
+  AuthInfo:
+    type: object
+    properties:
+      username:
+        type: string
+        example: username
+      first_name:
+        type: string
+        example: Usern
+      last_name:
+        type: string
+        example: A.
+      phone:
+        type: string
+        example: +123456789
+      is_bot:
+        type: boolean
+        example: false
+
   AuthSuccess:
     type: object
     properties: