Workflow Editions

The package version tells you which code you have. A workflow edition tells the runtime, environment, and model what a session means: how requests are ordered, when an episode ends, and how errors and values are handled. 2026.06 is the edition for the first public release. Its full contract is the reference for those semantics.

An edition is a declaration in the environment or model source. Set workflow_edition = "2026.06" on an EnvFactory or Model subclass after authoring it against that contract. The declaration stays put when you upgrade the package. rlmesh.current_workflow_edition() reports the base edition to use for a new declaration.

You can override it for one call with run(workflow_edition=...) or session(workflow_edition=...), or for a process with RLMESH_WORKFLOW_EDITION. Served peers can use ServeOptions(workflow_edition=...) or --workflow-edition. A project can declare [tool.rlmesh] workflow_edition in pyproject.toml. With no declaration, the peer uses its build’s newest edition and warns once.

How an edition is chosen

Peers advertise the editions they support and the one they prefer during the handshake. The runtime selects the highest edition all three participants support that none of their declarations excludes. It pins the result on the model’s ResolveAdapter request and the environment’s ConfigureEnv request. If there is no common edition, setup fails before the first step and reports what each participant offered. The current release retains one sealed edition.

An edition defines session behavior; it does not make every package or wire feature available to older peers. See Compatibility for the limits of cross-version sessions and the managed image version check.

Sealing the contract

The 0.1.0 release seals 2026.06: its specification is fixed, and a later change to the meaning of a conforming interaction requires another edition. A new optional feature or a fix that restores the documented behavior does not require a new edition.