Run & observe

Logs & traces

Every run on the platform — playground chats, swarm nodes, notebook calls — is recorded as a trace. Reading traces is the core debugging skill in agentic systems, and the one course environments almost never let you practice.

The traces table

/traces lists every run with the agent name, provider and model, latency, tokens in and out, dollar cost, status, and timestamp. Sort or scan for the rows that look wrong — the red statuses, the latency outliers, the runs that cost ten times their neighbours.

What a trace contains

Selecting a run opens the full record:

Metrics
Latency, tokens in, tokens out, and cost computed from model pricing.
Prompt
The prompt for the run, with the agent and model that handled it.
Tool calls
Each tool the model called, with the arguments it chose and the result it got back. If a tool you expected is never called, check the request payload to confirm it was offered at all.
Request / response payloads
The raw provider request and response. This is the ground truth: the exact message array, parameters, and tool definitions the model actually received, and exactly what it returned.
Error
For failed runs, the error message the runtime captured.

The playground inspector

While chatting in the Playground, the inspector panel shows the same information live, in three tabs: the latest request/response exchange, the stream of tool events as they happen (with a running call count), and the trace for the current conversation. For swarm runs, the observability view adds the per-node timeline.

A debugging method that works

  • Reproduce, then read. Re-run the failing input, open the trace, and read the request payload before forming a theory. Most "the model is broken" reports turn out to be "the model was sent something other than what I assumed".
  • Change one thing. Adjust a single line of prompt, one parameter, or the model — then run the same input and compare the two traces. Keeping the old trace open in a second tab is the closest thing prompt engineering has to a scientific method.
  • Watch cost as a signal. A run whose cost jumps an order of magnitude usually means a loop, a context blow-up, or a tool feeding the model far more text than intended — the trace shows which.
The Failure Modes Lab notebook and the canvas failure labs are guided practice for exactly this skill: each one produces a broken trace and asks you to find the cause.