Command-line reference

kern [--config <PATH>] <COMMAND>

--config selects a kern.toml. Without it, Kern walks upward from the current directory and uses the nearest one. kern verify ignores this option and never reads kern.toml; it requires an explicit manifest path.

Commands

Command	Purpose	GPU required
kern verify <MANIFEST>	Verify a manifest and print its serving protocol	No
kern run [TARGET]	Greedy single-sequence generation	Yes
kern test [TARGET]	A/B a candidate manifest against a reference	Yes
kern bench [TARGET]	Export raw program and call measurements	Yes
kern kernels [TARGET...]	Build and collect modules pinned by targets	Depends on inputs

Use kern <command> --help for all command-specific flags. That output is generated from the same option types the command parses.

Input precedence

For settings supported by both forms, an explicit command-line flag takes precedence over the selected target or section in kern.toml; configuration takes precedence over the built-in default.

Output and exit status

• Diagnostics and logs are written to stderr.
• kern run writes generated text to stdout.
• kern test --json writes one JSON object to stdout.
• kern verify exits with 1 when verification fails.
• kern verify logs verified at INFO level only after both manifest and serving protocol checks pass. Failures are logged at ERROR level; both go to stderr. The serving protocol summary goes to stdout on success.
• kern test exits with 0 for PASS, 1 for FAIL, and 2 for INCONCLUSIVE.

Environment

RUST_LOG controls log filtering. Device selection is explicit through --gpu or the gpu field in kern.toml.