Claude Code MCP Transport Disconnected After First Tool Call Rejection

What this error means

MCP error -32000: Connection closed → No such tool available is a Claude Code failure pattern reported for developers trying to fix claude code mcp server becoming permanently unreachable after first tool call is rejected by user permission prompt. Based on the imported evidence, treat this as a tool-specific troubleshooting page rather than a generic API error.

Why this happens

GitHub issue mlorentedev/hive: When the very first mcp__hive__* tool call is rejected via Claude Code permission prompt, every subsequent MCP call fails with ‘Connection closed’ then ‘No such tool available’. MCP server remains healthy at process level. Category mapping: AI Coding Tools (Claude Code + MCP integration).

Common causes

• GitHub issue mlorentedev/hive: When the very first mcp__hive__* tool call is rejected via Claude Code permission prompt, every subsequent MCP call fails with ‘Connection closed’ then ‘No such tool available’. MCP server remains healthy at process level. Category mapping: AI Coding Tools (Claude Code + MCP integration).

Quick fixes

1. Confirm the exact error signature matches MCP error -32000: Connection closed → No such tool available.
2. Check the Claude Code account, local tool state, and provider configuration involved in the failing workflow.
3. Compare the failing environment with a known working setup, then change one configuration value at a time.

Platform/tool-specific checks

• Verify the command, editor, extension, or API client that produced the error.
• Compare local settings with CI, deployment, or editor-level settings when the error appears in only one environment.
• Avoid deleting credentials, local model data, or project settings until the failing scope is clear.

Step-by-step troubleshooting

1. Capture the exact error message and the command, editor action, or request that triggered it.
2. Check whether the failure is account/auth, quota/rate, model/provider, local runtime, or deployment configuration.
3. Review the source evidence below and compare it with your environment.
4. Apply one change at a time and rerun the smallest failing action.
5. Keep the working fix documented for the team or deployment environment.

How to prevent it

• Keep provider/tool configuration documented.
• Record non-secret diagnostics such as tool version, provider name, model name, and command path.
• Add a lightweight check before CI or production workflows depend on the tool.

Sources checked

• https://github.com/mlorentedev/hive/issues

Evidence note: GitHub issue mlorentedev/hive: When the very first mcp__hive__* tool call is rejected via Claude Code permission prompt, every subsequent MCP call fails with ‘Connection closed’ then ‘No such tool available’. MCP server remains healthy at process level. Category mapping: AI Coding Tools (Claude Code + MCP integration).

Related errors

• AI Coding Tools

FAQ

What should I check first?

Start with the exact MCP error -32000: Connection closed → No such tool available text and the smallest action that reproduces it.

Can I ignore this error?

No. Treat it as a failed Claude Code workflow until the root cause is understood.

Is this guaranteed to have one fix?

No. The imported evidence supports the troubleshooting path above, but tool behavior can vary by account, plan, version, provider, and local configuration.

How do I know the fix worked?

Rerun the same command, editor action, or request. The fix is working when that action completes without MCP error -32000: Connection closed → No such tool available.