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serverInfo.icons.sizes is wrongly expecting a string and fails MCP connection #486

@sebastienros

Description

@sebastienros

Describe the bug

As per the specification the serverInfo.icons.sizes property is an array of objects.

When registering an MCP server using this property copilot-cli fails to initialize the session:

2025-11-05T22:44:02.640Z [ERROR] Failed to start MCP client for remote server aspire: [
  {
    "code": "invalid_type",
    "expected": "string",
    "received": "array",
    "path": [
      "serverInfo",
      "icons",
      0,
      "sizes"
    ],
    "message": "Expected string, received array"
  },
  {
    "code": "invalid_type",
    "expected": "string",
    "received": "array",
    "path": [
      "serverInfo",
      "icons",
      1,
      "sizes"
    ],
    "message": "Expected string, received array"
  },
...

Affected version

0.0.353 Commit: f8fd3e3

Steps to reproduce the behavior

Create an MCP tool returning an array for the icons.sizes property.

Expected behavior

MCP connection should go through.

Additional context

No response

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