# MCP Builder Error Handling

> Sub-skill of mcp-builder: Error Handling.

- Skill: `vamseeachanta/mcp-builder-error-handling` (Agent Skill)
- Install (CLI): `npx skillmds@latest add vamseeachanta/mcp-builder-error-handling`
- Raw SKILL.md: https://api.skillmd.com/api/skills/vamseeachanta/mcp-builder-error-handling/raw
- Safety review: PASS (external: skill-scanner PASS, skillspector PASS)
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: AI & ML
- Author: vamseeachanta (https://skillmd.com/u/vamseeachanta)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/vamseeachanta/mcp-builder-error-handling

---


# Error Handling

## Error Handling


### Common Errors


| Error | Cause | Solution |
|-------|-------|----------|
| `ECONNREFUSED` | Server not running | Start the MCP server process |
| `Tool not found` | Incorrect tool name | Check ListToolsRequestSchema handler |
| `Invalid arguments` | Schema mismatch | Validate against inputSchema |
| `Authentication failed` | Missing/invalid API key | Set environment variable correctly |
| `Timeout` | Slow response | Increase MCP_TIMEOUT or optimize handler |
### Error Template


```typescript
try {
  const result = await operation();
  return { content: [{ type: "text", text: JSON.stringify(result) }] };
} catch (error) {
  throw new Error(
    `Operation failed: ${error.message}. ` +
    `Please check your configuration and try again.`
  );
}
```