VTEX IO session transform apps

When this skill applies

Use this skill when your VTEX IO app integrates with the VTEX session system (vtex.session) to derive, compute, or propagate state that downstream transforms, the storefront, or checkout depend on.

• Building a session transform that computes custom fields from upstream session state (e.g. pricing context from an external backend, regionalization from org data)
• Declaring input/output fields in vtex.session/configuration.json
• Deciding which namespace your app should own and which it should read from
• Propagating values into public.* inputs so native transforms (profile, search, checkout) re-run
• Debugging stale session fields, race conditions, or namespace collisions between apps
• Designing B2B session flows where storefront-permissions, custom transforms, and checkout interact

Do not use this skill for:

• General IO backend patterns (use vtex-io-service-apps)
• Performance patterns outside session transforms (use vtex-io-application-performance)
• GraphQL schema or resolver design (use vtex-io-graphql-api)