fix typo

Author: lnhsingh

docs/evaluation/tutorials/agents.mdx

@@ -10,7 +10,7 @@ In this tutorial, we'll build a customer support bot that helps users navigate a
 
 - [Final response](../concepts#evaluating-an-agents-final-response): Evaluate the agent's final response.
 - [Trajectory](../concepts#evaluating-an-agents-trajectory): Evaluate whether the agent took the expected path (e.g., of tool calls) to arrive at the final answer.
-- [Single step](../concepts#evaluating-a-single-step-of-an-agent): Evaluate any agent step in isolation (e.g., whether it selects the appropriate first tool for a given ).
+- [Single step](../concepts#evaluating-a-single-step-of-an-agent): Evaluate any agent step in isolation (e.g., whether it selects the appropriate first tool for a given step).
 
 We'll build our agent using [LangGraph](https://github.com/langchain-ai/langgraph), but the techniques and LangSmith functionality shown here are framework-agnostic.