--- url: https://marimo-team.github.io/marimo-studio/reference/identities.md description: Stable names, revisions, generations, runtime identities, and state mappings. --- # Identities and state Studio binds every mutation, build, and presentation to the state it observed. Names identify durable product objects, revisions identify content, and generations identify replaceable owners and incarnations. The [glossary](glossary.md) defines the product objects themselves. ## Stable names | Identity | Format | Lifetime | | ------------------ | ----------------------------------------------------------------------------------- | ------------------------------------------------- | | View name | Lowercase letter followed by lowercase letters, digits, or hyphens | Stable until the view is renamed or removed | | Provider key | Canonical distribution plus entry-point registration, such as `marimo-studio/react` | Preserved by Studio Source mutations for one view | | Starter ID | Provider key plus local starter key, such as `marimo-studio/react:reveal` | Used during creation and not persisted | | Cell target | Native cell name or Studio cell alias | Stable while the notebook name or binding remains | | Value selector | Variable name plus permitted attribute and item steps | Resolves against the current notebook namespace | | Projection site ID | Lowercase artifact-local ID with at most 128 characters | Stable for one authored source site | ## Content revisions | Revision | Identifies | Changes when | | --------------------- | -------------------------------------------------------------------------------------------- | -------------------------------------------------------------------------------------- | | Source revision | Exact UTF-8 Source document content | The document bytes change. Public values use `sha256:` | | Notebook revision | Provider-visible static notebook record | Cell source, names, configuration, definitions, references, or dependency edges change | | Project revision | Complete normalized build-input snapshot plus provider provenance | A declared build input or provider build identity changes | | Artifact revision | Complete validated browser file tree and projection declarations | Any published artifact file or projection site changes | | Presentation revision | Selected view, saved notebook and configuration, build profile, and artifact | Any input to the delivered presentation changes | | Projection revision | Presentation projection targets, policy, runtime bindings, diagnostics, and runtime instance | Projection authorization or runtime binding state changes | An artifact revision stays current across repeated builds that produce a byte-identical browser file tree and the same projection declarations. Development and production profiles can publish the same artifact revision and still keep separate build attempt and publication state. ## Ownership generations | Generation | Identifies | Used by | | ------------------ | ------------------------------------------------------------------------ | ------------------------------------------------ | | Catalog generation | Studio configuration plus the current set of named view incarnations | Workspace mutation admission | | View generation | Durable owner of one name joined with the current view project directory | View write, build, export, and removal admission | Both generations are opaque 64-character lowercase hexadecimal strings. Read them from `status`, `view read --json`, or the Python handles that return them. Do not construct or persist them as long-term identifiers. `view write` checks the source revision, catalog generation, and view generation immediately before commit. A failed check preserves the current file and returns a conflict. Read the current source and retry from that state. [Errors and JSON](errors-and-json.md#public-error-classes) lists the conflict codes. Removing a view terminates its view generation. Renaming a view terminates the old name's generation and starts a generation for the new name. Recreating a name creates a new view generation. Existing Python `View` handles remain bound to the incarnation they observed. ## Runtime and browser identities | Identity | Scope | | ---------------------- | -------------------------------------------------------------------------------------------------------------------------------------- | | Runtime instance | One mounted notebook runtime configuration | | Runtime session ID | One Python runtime session. Browser runtimes have no server session ID | | Browser client ID | One connected Studio tab | | Presentation session | One browser admission to a presentation revision | | Projection instance ID | One active element in the browser [DOM](https://developer.mozilla.org/en-US/docs/Web/API/Document_Object_Model) at one projection site | The browser document exposes its committed presentation revision as `data-marimo-studio-revision` on ``, beside `data-marimo-studio-state`. An exact preview URL rejects a different presentation revision or unbuilt or failed view source, even when a previous artifact is retained. ## Workspace state `StudioOverview.state` and `marimo-studio status --json` use these values: | State | Meaning | | -------------- | -------------------------------------------------------------------------------- | | `unconfigured` | The notebook has no Studio configuration | | `needs-view` | Studio configuration exists and the default view project still needs creation | | `ready` | The configured workspace has at least one valid view and its default view exists | ## Build freshness `ViewInspection.freshness` and `view inspect --json` report development build freshness: | Freshness | Current source | Retained artifact | Meaning | | ---------- | --------------------- | ----------------- | ------------------------------------------------------------------------------------------- | | `current` | Matches | Present | The development artifact was built from the current project revision | | `stale` | Newer or invalid | Present | Preview can retain the last successful artifact while source needs another successful build | | `unbuilt` | Present | Absent | Current source has no successful development artifact | | `building` | Build in progress | Optional | Studio is preparing a candidate from the current snapshot | | `failed` | Latest attempt failed | Absent | No successful development artifact is available | `ViewInspection.build` describes the retained successful artifact and stays present when `freshness` is `stale`. ## Projection state Hosts use `connecting`, `loading`, `stale`, `ready`, `missing`, and `error`. See [Notebook result projections](projections.md#host-lifecycle) for DOM attributes and events. ## Validation state Validation levels are cumulative. [`marimo-studio validate`](cli.md#marimo-studio-validate) lists the evidence each level requires.