Agent Playground FAQ & fixes

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Hit a wall in the Agent Builder? Each fix below leads with what you see on screen, so scan for the message or symptom that matches yours. If your problem isn’t listed, reach out via support with the error text and the run or agent ID.

While building

The input I’m connecting to already has a source

An input port only accepts one incoming edge. Delete the existing edge into that input before drawing the new one.

See the full set in Limits & rules.

The node name I typed gets rejected

A node with this name already exists

Every node on the canvas needs a unique name, so pick a different one.

The prompt shows an inline error in the drawer

This prompt uses an unsupported output format. Only text-based prompts are supported in the agent builder.

Pick a text-based version of the prompt; see how to pick a prompt version in Configure an LLM Prompt node.

When saving or running

Save or Run shows an error toast

Node not configured, or 3 nodes are not configured when several are; the flagged nodes get highlighted on the canvas so you know which ones to open.

Open each flagged node’s drawer and finish its form; Configure an LLM Prompt node and Configure an Agent node cover what each form needs.

Graph contains a cycle. Remove the circular connection before saving.

The canvas lets you draw a connection that loops the graph back on itself; it’s only caught here, when you save or run. Remove the connection that closes the loop and save again.

Save Agent is greyed out

Several things gate this button, and it stays disabled until all of them clear:

• You’re not on the builder tab: switch back from Changelog or Executions
• You’re viewing a saved version, not the draft: see Manage versions for how to get back into a draft
• A run is still in flight: wait for it to finish
• The canvas is still loading: wait for it to finish
• You don’t have permission to edit this agent. Hover the button for the tooltip: You don't have permission to edit this agent. See Roles & Permissions for who can grant you edit access

Run Agent Workflow is greyed out

This is gated by the same edit permission as Save Agent. Hover the button for the tooltip: You don't have permission to run this agent. See Roles & Permissions for who can grant you edit access.

The run won’t start

Fill in all variables before running, or Failed to validate variables if the check itself can’t complete.

The builder opens the Variables drawer for you and queues the run behind it, so fill in what’s missing there; see Set input variables.

The whole run shows as failed

If the toast reads Workflow execution failed, the run never started. Retry it, and if it keeps failing to start, send support the agent ID.

Otherwise, the toast carries the failed node’s own error message. Open the run panel, find the failed node, and fix it; see Run an agent.

During a run

The run started, but a node’s status badge shows skipped

A node is marked skipped, rather than run, when the step feeding it failed. Fix the failed node upstream and rerun; see Run an agent for how the run panel shows each node’s status.

Managing agents

I got bounced to the agents list with a missing-agent message

Missing agent

The builder shows this and sends you back to the agent list when the URL you opened carries no agent ID at all. Open the agent again from the list instead; see Create an agent.

An agent won’t delete

An agent stays undeletable while another agent’s node still references one of its versions. Open the referencing agent, remove or swap out that node, then delete again; see Create an agent.

The last version of an agent won’t delete

An agent always keeps at least one version, so its last one can’t be removed. Add a new version first if you want to retire the old one; see Manage versions.

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