1 files changed, 1 insertions, 1 deletions
diff --git a/synapse/logging/tracing.py b/synapse/logging/tracing.py
index e3a1a010a2..109ae185e1 100644
--- a/synapse/logging/tracing.py
+++ b/synapse/logging/tracing.py
@@ -876,7 +876,7 @@ def tag_args(func: Callable[P, R]) -> Callable[P, R]:
     def _tag_args_inner(*args: P.args, **kwargs: P.kwargs) -> R:
         argspec = inspect.getfullargspec(func)
         for i, arg in enumerate(argspec.args[1:]):
-            set_attribute("ARG_" + arg, str(args[i]))  # type: ignore[index]
+            set_attribute("ARG_" + arg, str(args[i + 1]))  # type: ignore[index]
         set_attribute("args", str(args[len(argspec.args) :]))  # type: ignore[index]
         set_attribute("kwargs", str(kwargs))
         return func(*args, **kwargs)