CommandsApps
skytells logs
Stream or retrieve logs for a Skytells app — runtime, build, and system event streams.
Overview
skytells logs retrieves log output for a specific app. You can tail live output, filter by log type, and limit output volume. This is the primary tool for runtime debugging and incident investigation.
Syntax
skytells logs <app> [--type <type>] [--tail <n>] [--follow] [--json]Arguments
| Argument | Description |
|---|---|
app | The app ID to stream logs from (begins with app_). |
Flags
| Flag | Default | Description |
|---|---|---|
--type <type> | runtime | Log stream to query. See types below. |
--tail <n> | 50 | Number of recent lines to show. |
--follow | — | Stream log output continuously (like tail -f). |
--json | — | Output as NDJSON (one JSON object per line). |
Log types
| Type | Stream contents |
|---|---|
runtime | Application stdout/stderr — your app's actual output |
build | Build step output — compiler output, dependency installation |
system | Platform events — container restarts, health check results, scaling events |
Examples
# See the last 50 runtime log lines
skytells logs app_abc123
# Stream live runtime logs
skytells logs app_abc123 --follow
# Last 200 lines of runtime logs
skytells logs app_abc123 --tail 200
# Build logs for a deployment
skytells logs app_abc123 --type build
# System events (restarts, health checks)
skytells logs app_abc123 --type system
# Stream build logs in real-time during a deployment
skytells logs app_abc123 --type build --follow
# JSON output — stream one log object per line
skytells logs app_abc123 --json
# Filter for errors in JSON output
skytells logs app_abc123 --json | jq 'select(.level == "error")'
# Filter logs containing a keyword
skytells logs app_abc123 | grep "ERROR"Live streaming
When --follow is active, the CLI stays connected and prints new log lines as they arrive. Press Ctrl+C to stop streaming.
Live streaming (--follow) works in interactive terminals. In CI/CD pipelines where there is no TTY, omit --follow and use polling instead.
Log retention
Logs are retained for 30 days. For longer retention, export logs to your own observability stack. Use --json output with a log forwarder in your CI/CD pipeline or as a cron job:
# Export today's runtime logs to a file
skytells logs app_abc123 --tail 10000 --json > logs-$(date +%F).ndjsonHow is this guide?