osl CLI

The osl binary drives the authoring loop for developers and CI.

Commands

Command	Purpose
`osl validate <project_dir>`	JSON Schema + cross-references + dbt model existence
`osl compile <project_dir> [--output target/]`	Emit the canonical `manifest.json`
`osl plan <project_dir> <query>`	Dry-run a query — inspect SQL/retrieval plan + policy check
`osl publish <project_dir> --to <engine>`	Upload the manifest (atomic; `--revert`)
`osl migrate from-metricflow <src> <dst>`	Generate an OSL project from a MetricFlow project
`osl export to-metricflow <src> <dst>`	Export an OSL project as pure MetricFlow
`osl test <project_dir>`	Golden SQL, chunk-schema, joint round-trip, lexicon tests
`osl conformance test --level <level> <project_dir>`	Run the official conformance suite

Example

$ osl validate ./caixabank-cartera-eu/
✔ project.yml                                      valid
✔ models/customers.yml                             valid (3 models, 12 dimensions, 4 measures)
✔ metrics/arr.yml                                  valid
✗ facets/meeting_transcripts.yml                   2 errors
   E0201 chunk_schema missing required field 'embedding'  at line 12
   E0204 embedding.provider == tenant-byo requires .adapter  at line 18
✔ joints/customer.yml                              valid

Summary: 5 files valid, 1 file with errors. Exit code: 1.

Reference clients Apache-2.0

The reference engine ships two client libraries (the spec does not require them — any HTTP client works):

Python — pyosl (REST + MCP). Recommended for Dagster jobs, dbt extensions, scripts.
TypeScript — osl-client (REST). For web apps and Node.js.