Codex wiring Datasette traces is not an agent supervision trace

October 6, 2026, Simon Willison's firsthand TIL. After Datasette gained OpenTelemetry support, Willison had Codex work out how to run Parseable and send Datasette traces to it; he wrote up the working procedure himself and showed an application trace in Parseable. A developer can delegate observability setup, but the observed spans here are from the app, not documented measures of agent decisions, human review time or post-release customer requests. No issue→review→release ledger or comparison is supplied. This is useful as a distinction for agent supervision: instrumenting the software an agent touches does not automatically instrument the agent's work or its human overhead. Passed on a separate feed post amid older unread items.