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VS Code rejects component_builder and element_builder due to invalid array schema: tool parameters array type must have items #119

@timcoy47

Description

@timcoy47

We are seeing VS Code reject Webflow MCP builder tools during tool validation before execution.

Affected tools
component_builder
element_builder
Error
Failed to validate tool mcp_webflow_component_builder:
Error: tool parameters array type must have items
We are seeing the same class of issue for element_builder.

What this suggests
This looks like a tool-schema compatibility issue rather than a sampling or bridge issue.

The MCP server is reachable enough for tool discovery, but VS Code rejects these tools during schema validation.

Likely source location
The likely cause appears to be the recursive builder child schema definitions in:

src/tools/deComponents.ts
src/tools/deElement.ts
In particular, the builder schemas appear to use loose recursive array shapes such as:

children: z.array(z.any())
That may be generating JSON Schema arrays without concrete items, which VS Code then rejects.

Expected behavior
VS Code should be able to validate and register these tools.

Actual behavior
VS Code rejects the tools during validation, making them unusable even though the MCP server is otherwise reachable.

Environment
Client: VS Code with MCP support / Copilot chat
Server: Webflow MCP remote server
Builder tools affected: component_builder, element_builder
Requested fix
Please update the builder tool schemas so array parameters emit explicit items in JSON Schema.

Using explicit recursive schemas rather than loose z.array(z.any()) shapes would likely resolve this for strict MCP clients.

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