## Summary - harden MCP runtime behavior around asset uploads and resources, HTTP responses, component and Content Block application, data reads, and Chromium screenshots - reject shared Slots inside Content Block templates and avoid unsafe unused-asset findings when Content Blocks can hide MDX dependencies - expand named grid-area values according to CSS shorthand fallback rules - add a consent-safe YouTube preconnect control and only warm origins that are actually used - add focused and end-to-end regression coverage for the reported paths ## Verification - project-build: 2,419 tests passed - css-data: 4,623 tests passed, 1 skipped - sdk-components-react: 134 tests passed, 1 skipped - high-impact CLI fixture: 7 tests passed - Builder asset REST service: 22 tests passed Closes #6336 Closes #6339 Closes #6353 Closes #6354 Closes #6355 Closes #6356 Closes #6357 Closes #6358 Closes #6359
Protocol
@webstudio-is/protocol owns Webstudio data exchange protocols.
The project bundle is the external export/import artifact used by sync, local
.webstudio/data.json, project import, transferred asset files, and prebuild.
This package owns the assembled bundle schemas, transfer RPC payloads, and
bundle compatibility/version helpers.
Domain models such as pages, assets, and serialized builds remain owned by their domain packages and are composed here through schema-only entrypoints. Do not copy those schemas into this package.
Terminology
Project bundle is the authoritative external project artifact. It is used by
sync, .webstudio/data.json, project import, transferred asset files, and
prebuild.
Data envelope is a serialized single-key object whose key is a versioned
Webstudio marker, for example { "@webstudio/instance/v0.1": data }. The
envelope identifies the payload version and lets consumers detect malformed
Webstudio-owned data before falling back to other formats.
Transfer data is the domain payload inside a data envelope. Examples include
InstanceTransferData, InstancesTransferData, and PageTransferData.
Transfer data is portable and detached from a project; insertion/import remaps
ids and merges it into authoritative project state. Runtime-owned transfer
formats live in @webstudio-is/project-build/transfer.
Clipboard data is a UI transport concern. Builder copy/paste may serialize transfer data into a data envelope and place it on the browser clipboard, but runtime and protocol code should name the reusable format as data envelope or transfer data, not clipboard.