Update index.rst

Author: franzwilding

src/agent/doc/index.rst

@@ -332,7 +332,7 @@ to skip the next LLM call by setting a result yourself::
     });
 
 Tool Call Lifecycle Events
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 If you need to react more granularly to the lifecycle of individual tool calls, you can listen to the
 ``ToolCallArgumentsResolved``, ``ToolCallSucceeded`` and ``ToolCallFailed`` events. These are dispatched at different stages::