fix: skip tool output validation on error

[codefromthecrypt]

Summary

When a tool returns an error, the output is not guaranteed to conform to the output schema. This change skips the output schema validation when the tool result is an error, preventing incorrect validation errors from being shown.

Type of Change

• Bug fix (non-breaking change that fixes an issue)
• New feature (non-breaking change that adds functionality)
• Documentation update
• Refactoring (no functional changes)
• Test updates
• Build/CI improvements

Changes Made

• In ToolResults.tsx, added a check to skip output schema validation if the tool result is an error.
• Added a new test case in ToolsTab.test.tsx to ensure that output validation is skipped for error results.

Related Issues

Testing

• Tested in UI mode
• Tested in CLI mode
• Tested with STDIO transport
• Tested with SSE transport
• Tested with Streamable HTTP transport
• Added/updated automated tests
• Manual testing performed

Test Results and/or Instructions

The new test case in ToolsTab.test.tsx covers the changes.

Checklist

• Code follows the style guidelines (npm run prettier-fix)
• Self-review completed
• Code is commented where necessary
• Documentation updated (README, comments, etc.)

Breaking Changes

None.

Additional Context

Failure case:

$ npx @modelcontextprotocol/inspector  http://localhost:64345/stream --cli --transport http --method tools/call      --tool-name get_repositories
  Failed to call tool get_repositories: MCP error -32602: Structured content does not match the tool's output schema: data must have required property 'roots'

  Failed with exit code: 1

[codefromthecrypt]

this only addresses the UI not the CLI.. will undraft when it is both

[codefromthecrypt]

wrong repo I think this has to be fixed in the SDK itself

[codefromthecrypt]

modelcontextprotocol/typescript-sdk#1428 solves this