[BUG] Microsoft Dataverse MCP connector fails with "missing required resultType" on every call in Claude Code (works fine in claude.ai chat)

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

The claude.ai Microsoft Dataverse MCP connector is completely non-functional inside Claude Code (VS Code extension), failing on every single tool call — including the most basic ones (e.g. listing all tables). The identical connector works normally in regular claude.ai chat mode with the same account/connection.

What Should Happen?

Should be able to use tools

Error Messages/Logs

MCP server "claude.ai Microsoft Dataverse" returned a malformed result that failed schema validation: Invalid result for tools/call: missing required resultType — servers implementing protocol revision 2026-07-28 MUST include it (the absent-means-complete bridge applies only to earlier-revision servers)

Steps to Reproduce

1) Connect the Microsoft Dataverse MCP server (via claude.ai integrations) to a Claude Code session.
2) Call any tool on it, e.g. describe with path tables/ or tables/{any_table_name}.
3) Observe the error below.
4) Compare against claude.ai chat mode, where the same connector and the same calls succeed normally.

Claude Model

_No response_

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

2.1.237

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

VS Code integrated terminal

Additional Information

The error message suggests the Dataverse MCP server has been updated to implement MCP protocol revision 2026-07-28 and now always includes a resultType field in its tools/call responses. Claude Code's MCP client appears to still expect the older "absent-means-complete" behavior and rejects responses that include resultType, causing schema validation to fail. Since the same server works in claude.ai chat, the client-side MCP handling likely differs between the two surfaces and Claude Code's has not been updated to the newer protocol revision.