[BUG] Clean up MCP testing client #582

Describe the bug

This is bloated technical debt introduced in PR #581.

To Reproduce

N/A.

Expected behavior

Remove the bodge, creating / changing more sophisticated tests as needed. No tests are to be removed.

Screenshots
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Desktop (please complete the following information):

• OS: [e.g. iOS]
• Browser [e.g. chrome, safari]
• Version [e.g. 22]

Smartphone (please complete the following information):

• Device: [e.g. iPhone6]
• OS: [e.g. iOS8.1]
• Browser [e.g. stock browser, safari]
• Version [e.g. 22]

Additional context
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