once toolchain
Inspect the project toolchain contract
Synopsis
text
once toolchain [OPTIONS] <SUBCOMMAND>Description
Reports the toolchains a project pins (Rust, Swift, mise) and the resolved versions Once will use when running actions from script adapters or graph target kinds. Pair with once query schema when debugging "why did the cache miss?" questions where the toolchain identity is suspect.
Options
| Flag | Value | Default | Description |
|---|---|---|---|
-C, --directory | <DIR> | Project root. Defaults to the current directory; the cache lives under <project>/.once/. Mirrors make -C | |
--format | <FORMAT> | human | Output format for Once's structured data (cache stats, run/exec trailers). Defaults to a human-readable rendering; pass json or toon to get machine-parseable output for scripting and for agent consumers |
-v, --verbose | (flag) | 0 | Increase log verbosity. Repeat for more (-v: info, -vv: debug, -vvv: trace). Overridden by RUST_LOG |
-q, --quiet | (flag) | false | Suppress human-mode success and progress trailers. Errors and the structured envelope of --format json/toon still print. Mirrors the -q flag of common build tools |
--list | (flag) | false | Print the command surface at the current command depth |