docs: add tracing metadata option to AI Agent docs (#4220)

Co-authored-by: Rowena Jones <36301604+RoRoJ@users.noreply.github.com>

_snippets/integrations/builtin/cluster-nodes/langchain-root-nodes/tracing-metadata.md

@@ -0,0 +1,3 @@
+Add custom key-value metadata to tracing events for this agent. This is useful for filtering and debugging runs in tracing tools like [LangSmith](/advanced-ai/langchain/langsmith.md).
+
+Entries with empty keys or values are ignored.

docs/integrations/builtin/cluster-nodes/root-nodes/n8n-nodes-langchain.agent/conversational-agent.md

@@ -77,6 +77,10 @@ Here is the user's input (remember to respond with a markdown code snippet of a
 
 --8<-- "_snippets/integrations/builtin/cluster-nodes/langchain-root-nodes/return-intermediate-steps.md"
 
+### Tracing Metadata
+
+--8<-- "_snippets/integrations/builtin/cluster-nodes/langchain-root-nodes/tracing-metadata.md"
+
 ## Templates and examples
 
 Refer to the main AI Agent node's [Templates and examples](/integrations/builtin/cluster-nodes/root-nodes/n8n-nodes-langchain.agent/index.md#templates-and-examples) section.

docs/integrations/builtin/cluster-nodes/root-nodes/n8n-nodes-langchain.agent/openai-functions-agent.md

@@ -45,6 +45,10 @@ Refine the OpenAI Functions Agent node's behavior using these options:
 
 --8<-- "_snippets/integrations/builtin/cluster-nodes/langchain-root-nodes/return-intermediate-steps.md"
 
+### Tracing Metadata
+
+--8<-- "_snippets/integrations/builtin/cluster-nodes/langchain-root-nodes/tracing-metadata.md"
+
 ## Templates and examples
 
 Refer to the main AI Agent node's [Templates and examples](/integrations/builtin/cluster-nodes/root-nodes/n8n-nodes-langchain.agent/index.md#templates-and-examples) section.

docs/integrations/builtin/cluster-nodes/root-nodes/n8n-nodes-langchain.agent/plan-execute-agent.md

@@ -37,6 +37,10 @@ Available LangChain expressions:
 * `{current_step}`: Contains information about the current step.
 * `{agent_scratchpad}`: Information to remember for the next iteration.
 
+### Tracing Metadata
+
+--8<-- "_snippets/integrations/builtin/cluster-nodes/langchain-root-nodes/tracing-metadata.md"
+
 ## Templates and examples
 
 Refer to the main AI Agent node's [Templates and examples](/integrations/builtin/cluster-nodes/root-nodes/n8n-nodes-langchain.agent/index.md#templates-and-examples) section.

docs/integrations/builtin/cluster-nodes/root-nodes/n8n-nodes-langchain.agent/react-agent.md

@@ -65,6 +65,10 @@ Add text to append after the tools list at the start of the conversation when th
 
 --8<-- "_snippets/integrations/builtin/cluster-nodes/langchain-root-nodes/return-intermediate-steps.md"
 
+### Tracing Metadata
+
+--8<-- "_snippets/integrations/builtin/cluster-nodes/langchain-root-nodes/tracing-metadata.md"
+
 ## Related resources
 
 Refer to LangChain's [ReAct Agents](https://js.langchain.com/docs/concepts/agents/) documentation for more information.

docs/integrations/builtin/cluster-nodes/root-nodes/n8n-nodes-langchain.agent/sql-agent.md

@@ -85,6 +85,10 @@ Enter the maximum number of results to return.
 
 Default is `10`.
 
+### Tracing Metadata
+
+--8<-- "_snippets/integrations/builtin/cluster-nodes/langchain-root-nodes/tracing-metadata.md"
+
 ## Templates and examples
 
 Refer to the main AI Agent node's [Templates and examples](/integrations/builtin/cluster-nodes/root-nodes/n8n-nodes-langchain.agent/index.md#templates-and-examples) section.

docs/integrations/builtin/cluster-nodes/root-nodes/n8n-nodes-langchain.agent/tools-agent.md

@@ -174,6 +174,10 @@ Refine the Tools Agent node's behavior using these options:
 
 --8<-- "_snippets/integrations/builtin/cluster-nodes/langchain-root-nodes/return-intermediate-steps.md"
 
+### Tracing Metadata
+
+--8<-- "_snippets/integrations/builtin/cluster-nodes/langchain-root-nodes/tracing-metadata.md"
+
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