Claude Code Corrupts mcpServers Config with Nested Key in ~/.claude.json

What this error means

mcpServers.mcpServers: Does not adhere to MCP server configuration schema is a Claude Code failure pattern reported for developers trying to fix claude code mcp server configuration corruption error. Based on the imported evidence, treat this as a tool-specific troubleshooting page rather than a generic API error.

Why this happens

Claude Code 2.1.133 on macOS creates nested mcpServers.mcpServers key inside global mcpServers object when writing ~/.claude.json. Per-project entries with mcpServers: {} cause the serializer to nest incorrectly. /doctor reports schema validation failure.

Common causes

• Claude Code incorrectly nests mcpServers inside itself when writing ~/.claude.json at session end, breaking all MCP integrations in subsequent sessions. /doctor shows parse error.
• Claude Code 2.1.133 on macOS creates nested mcpServers.mcpServers key inside global mcpServers object when writing ~/.claude.json. Per-project entries with mcpServers: {} cause the serializer to nest incorrectly. /doctor reports schema validation failure.

Quick fixes

1. Confirm the exact error signature matches mcpServers.mcpServers: Does not adhere to MCP server configuration schema.
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/anthropics/claude-code/issues/58919

Evidence note: Claude Code 2.1.133 on macOS creates nested mcpServers.mcpServers key inside global mcpServers object when writing ~/.claude.json. Per-project entries with mcpServers: {} cause the serializer to nest incorrectly. /doctor reports schema validation failure.

Related errors

• Claude Code /doctor MCP parse error
• Claude Code ~/.claude.json corrupted
• MCP server config schema validation failed

FAQ

What should I check first?

Start with the exact mcpServers.mcpServers: Does not adhere to MCP server configuration schema 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 mcpServers.mcpServers: Does not adhere to MCP server configuration schema.