Logs - Agent SDK for Go

All examples route user-facing output to stdout and SDK internal logs to stderr. SDK logging is off by default (LOG_ENABLE=false); set LOG_ENABLE=true and LOG_LEVEL when debugging. Source: examples/logs/

Output routing

Output	Destination
User prompt and assistant reply	stdout
SDK internal logs	stderr (when `LOG_ENABLE=true`)

Usage

From examples/:

go run ./simple_agent "Hello"                                    # default: no SDK logs
LOG_ENABLE=true LOG_LEVEL=debug go run ./simple_agent "Hello"    # enable for debugging
LOG_ENABLE=true LOG_LEVEL=info go run ./simple_agent "Hello" 2>debug.log

Variable	Default	Description
`LOG_ENABLE`	`false`	`false` → `NoopLogger` (no SDK logs); `true` → real logger at `LOG_LEVEL`
`LOG_LEVEL`	`error`	`debug`, `info`, `warn`, `error` — ignored when `LOG_ENABLE=false`

Optional run footers: SHOW_LLM_USAGE=true, SHOW_TELEMETRY=true — see Running Examples. For OTLP log export, see Observability. For file logging in the REPL, see CLI.

Learn more

Logs

SDK logging and OTLP export

Telemetry

Per-run telemetry footers