How do I resolve the 'credentials not found' error when using an HTTP node with an AI Agent?

Below is a checklist to help troubleshoot and fix the “credentials not found” error when using an HTTP Request node as a tool within an AI Agent workflow:

1. Verify Credential Configuration in the Tool Node

Even if your stand-alone HTTP Request node works, the tool node used by the agent must be configured with the correct credentials as well. Open the tool node and ensure that:

• The credential dropdown shows the expected credential.
• You’re using the correct Predefined Credential Type (if applicable).

2. Re-Add or Refresh the Node

Sometimes the underlying node version might not have updated the credential reference properly. Try the following steps:

• Remove the HTTP Request node from your AI Agent workflow.
• Re-add it and re-select the proper credentials from the dropdown.
  This ensures the node is using the latest configuration and version.

3. Confirm Consistency with Stand-Alone Setup

Compare every setting between your working stand-alone HTTP Request node and the one used as a tool in the AI Agent. In particular, double-check:

• The authentication method.
• Any expressions or dynamic properties that might inadvertently cause a null or missing credential reference.

4. Check for Version-Specific Issues

If the HTTP Request node was copied from an earlier workflow template, it might be using an older configuration. Re-adding it as described above ensures that you’re working with the up-to-date node.

Following these steps should resolve the “credentials not found” error when the HTTP Request node is used with your AI Agent. If issues persist, consulting the n8n documentation or community forum for further troubleshooting might help.