Fix: Change create_view elements from JSON string to typed array

[anmolxlight]

Problem

create_view accepts elements as z.string() — a raw JSON array string. Models frequently generate invalid JSON in this string (trailing commas, unquoted keys, comments), causing silent "Invalid JSON in elements" errors. Since the schema doesn't enforce structure, strict tool use features (Claude structured outputs, ChatGPT function calling) can't help.

Fix

Changed elements from z.string() to z.array(z.record(z.any())). This lets Zod validate the array structure directly, enabling structured output / strict tool use to generate valid input.

Before:

{
  "elements": "[{"type": "rectangle", "x": 10}]"
}

After:

{
  "elements": [{"type": "rectangle", "x": 10}]
}

The widget (mcp-app.tsx line 432) already handles both string and array inputs via typeof check, so no frontend changes needed.

Changes

• src/server.ts: Changed schema from z.string() to z.array(z.record(z.any())), removed manual JSON.parse block, updated size check to use JSON.stringify(elements).length
• CLAUDE.md: Updated create_view description

Related

Fixes #56

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