Prometheus

Prometheus is the canonical open source monitoring server, with a companion promtool CLI for validating configs, testing rules, querying servers, and inspecting TSDB data. For clis.dev, the durable CLI value comes mostly from those operational workflows rather than from daemon startup alone.

• Run Prometheus in server or agent mode with flags for storage, web and API exposure, feature flags, and reload behavior.
• Validate Prometheus configs, web configs, and rule files, and unit test alerting or recording rules before rollout.
• Query a live Prometheus, inspect service-discovery results or TSDB contents, fetch debug bundles, and push sample metrics for testing.

• Best in inspect/change/verify loops around Prometheus operations: linting, rule tests, ad hoc queries, and TSDB inspection are non-interactive and scriptable.
• The companion promtool supports structured output for queries and TSDB dumps, and the server can emit JSON logs for downstream parsing.
• Much of the real workflow still depends on a running Prometheus instance, config files, and HTTP endpoints, so it is less self-contained than remote-service CLIs.

• Official docs recommend released binaries from the download page; go install is source-oriented and comes with web-asset caveats.
• The prometheus binary is primarily a long-running daemon, so many useful CLI commands either target an existing server or operate on local TSDB data.