Tool Parameter Updates not applied

[patrickcbrown]

Inspector Version

• 0.18.0

Describe the bug
When editing JSON parameter values for tools in the Inspector UI, updated values are not sent when clicking "Run Tool". The tool call continues to use the original/stale parameter values instead of the newly entered values.

To Reproduce

1. Start the MCP Inspector and connect to an MCP server that has tools with object parameters, set one of the JSON parameter fields (e.g., {"key": "value1"}) observe the tool executes correctly with the entered value
2. Update that value to something different (e.g., {"key": "value2"}) then click "Run Tool", observe in the History control that the previous value is shown in the payload and the response in fact does correspond to the old value

Expected behavior
When a parameter value is updated and "Run Tool" is clicked, the tool should be called with the current parameter values as shown in the editor.

Screenshots

Environment (please complete the following information):

• OS: windows 10
• Browser chrome, edge

Additional context
I can work around this by clicking "Switch to Form" after each modification of the Parameter value

Version Consideration
I backed up a to 0.17.5 and was able to see the same issue

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