Drive MCP tool definitions and dispatch from proto messages#11368
Merged
tronical merged 3 commits intoslint-ui:masterfrom Apr 14, 2026
Merged
Drive MCP tool definitions and dispatch from proto messages#11368tronical merged 3 commits intoslint-ui:masterfrom
tronical merged 3 commits intoslint-ui:masterfrom
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Replace hand-written JSON schemas and manual string parsing with proto-driven generation: - Add RequestGetElementTree, RequestDispatchKeyEvent, and KeyEventType to slint_systest.proto so all 12 MCP tools have proto counterparts - Generate JSON schemas from proto descriptors at build time in build.rs - Replace 160 lines of hand-written JSON with a declarative TOOLS table mapping tool names to proto request types - Unify all tool handlers to use deserialize_params with proto types, eliminating manual string matching for enums and field extraction
Add match arms for RequestDispatchKeyEvent and RequestGetElementTree in the binary system-testing transport. These are MCP-only tools, so return an error when received over the system-testing channel.
tronical
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Apr 14, 2026
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Thanks, that looks like a small overall reduction - worth it :)
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Summary
Addresses review feedback from #11340: replace hand-written JSON schemas and manual string parsing in the MCP server with proto-driven generation.
RequestGetElementTree,RequestDispatchKeyEvent, andKeyEventTypeenum toslint_systest.protoso all 12 MCP tools have proto request counterpartsbuild.rsTOOLStable mapping tool names to proto request typesdeserialize_paramswith proto types, eliminating manual string matching for enums and manual JSON field extractionBreaking change for MCP clients:
drag_elementnow takestarget: { x, y }(matching the protoLogicalPosition) instead of flattargetX/targetY.dispatch_key_eventenum values changed from snake_case (press_and_release) to PascalCase (PressAndRelease) to match proto conventions.Test plan
cargo build -p i-slint-backend-testing --features mcpcompilescargo test -p i-slint-backend-testing --features mcp -- mcp— all 19 tests passtest_all_tools_have_proto_schemasvalidates every tool'srequest_typeresolves to a generated schema and alloptional_fieldsare real proto fields