docker mcp tools call double-encodes JSON arguments breaking all tool calls

[Echo-Computing]

Bug Description

The docker mcp tools call <tool> CLI command double-encodes JSON arguments, causing all tool calls to fail.

Steps to Reproduce

1. Run docker mcp tools call git_status --args '{"repo_path": "/repo"}'
2. Observe verbose output: Calling tool git_status with arguments: {"{\"repo_path\": \"/repo\"}":null}

Expected vs Actual

• Expected: Gateway receives {"repo_path": "/repo"} as a proper JSON object
• Actual: Arguments become a STRING KEY {"repo_path": "/repo"} with value null

Impact

• All docker mcp tools call commands fail
• Gateway works fine when called from Claude Code (which handles JSON correctly)
• This only affects CLI-based testing of the MCP gateway

Environment

• Docker Desktop on Windows (WSL2 backend)
• Docker MCP Toolkit CLI

[github-actions]

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[mickn277]

Can confirm I've hit the same issue.
Docker v 4.72.0
All docker mcp tools call commands fail
Gateway works fine when called from ZooCode (was RooCode)
Affects powershell CLI-based testing of the MCP gateway.