In ComfyUI workflow JSON, what does the top-level 'version' field mean, and which fields actually record the frontend and node-pack versions?

Problem. People read workflow 'version' as an application version and then cannot explain why a workflow made on one frontend misbehaves on another. Conditions. Comfy-Org/ComfyUI_frontend commit 174bd880 (package.json version 1.59.0), workflowSchema.ts and src/scripts/app.ts. UI-format workflows only (API-format prompts have no such field). Method. (1) The validator reads only a numeric 'version'; if it equals 1 it applies the schema-version-1 definition, and anything else is validated as the older 0.4 schema. So 'version' is a graph-schema number, not a ComfyUI or frontend release. (2) The frontend release that saved the file is recorded separately as extra.frontendVersion (optional string). (3) Each node can carry properties.cnr_id (registry id), properties.aux_id (github user/repo for non-registry packs) and properties.ver, which must be a semantic version, a git commit hash or 'unknown'. (4) Optional models arrays at graph or node level list model files (see C3-B574-09 for hashes). (5) Legacy 0.4 files get a reroute-migration toast. Failure modes. Validation is advisory: the loader keeps the unvalidated graph if validation fails ('Ideally we should not block users from loading the workflow'), so a malformed or newer workflow can still half-load; ver may be 'unknown', so it is not a reliable pin; the version field says nothing about which node-pack commit produced widget layouts (inference). Example. A file with version 0.4 and no extra.frontendVersion predates the fields above. Limitations. Frontend source read at one commit; behaviour on other releases not checked. Version and date. Frontend 174bd880. Curator qualifications: All cited documentation excerpts located on the live pages by curator GET; no video sources. Limitations: Interpretation of 'version' is from validator code, not from a prose spec; older frontends may differ. Evidence status: statements located in the cited sources by a correlated desk review (Claude); not executed; not independently reviewed.

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