Cline/MCP tool calls fail with Pydantic ValidationError due to incorrect task_progress parameter

What this error means

Pydantic ValidationError: task_progress parameter incorrectly passed to MCP tool calls is a Cline (Claude Code) failure pattern reported for developers trying to fix pydantic validation errors when cline passes task_progress parameter to jira mcp tool calls, blocking automated task management workflows. Based on the imported evidence, treat this as a tool-specific troubleshooting page rather than a generic API error.

Why this happens

GitHub issue #10737 in cline/cline (opened May 14, 2026). Cline’s MCP integration incorrectly passes task_progress param to certain tool calls, causing Pydantic ValidationError. Active issue with comments. Directly impacts developers using AI coding assistants with project management integrations. Maps to ‘AI Coding Tools’.

Common causes

• GitHub issue #10737 in cline/cline (opened May 14, 2026). Cline’s MCP integration incorrectly passes task_progress param to certain tool calls, causing Pydantic ValidationError. Active issue with comments. Directly impacts developers using AI coding assistants with project management integrations. Maps to ‘AI Coding Tools’.

Quick fixes

1. Confirm the exact error signature matches Pydantic ValidationError: task_progress parameter incorrectly passed to MCP tool calls.
2. Check the Cline (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/cline/cline/issues/10737

Evidence note: GitHub issue #10737 in cline/cline (opened May 14, 2026). Cline’s MCP integration incorrectly passes task_progress param to certain tool calls, causing Pydantic ValidationError. Active issue with comments. Directly impacts developers using AI coding assistants with project management integrations. Maps to ‘AI Coding Tools’.

Related errors

• AI Coding Tools

FAQ

What should I check first?

Start with the exact Pydantic ValidationError: task_progress parameter incorrectly passed to MCP tool calls text and the smallest action that reproduces it.

Can I ignore this error?

No. Treat it as a failed Cline (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 Pydantic ValidationError: task_progress parameter incorrectly passed to MCP tool calls.