examples/mcp_calculator.py is not working for me or others who tried it

[Riehantunut]

claude-code-sdk==0.0.21
Claude Code v1.0.109

When running examples/mcp_calculator.py others and I get these printouts:

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Prompt: List your tools
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Claude: Here are the tools I have available:

**File Operations:**
- `Read` - Read file contents
- `Write` - Write/overwrite files
- `Edit` - Make exact string replacements in files
- `MultiEdit` - Make multiple edits to a single file
- `NotebookEdit` - Edit Jupyter notebook cells

**Search & Navigation:**
- `Glob` - Find files by pattern (e.g., "**/*.py")
- `Grep` - Search file contents with regex
- `Task` - Launch specialized agents for complex searches

**Shell Operations:**
- `Bash` - Execute shell commands
- `BashOutput` - Get output from background processes
- `KillBash` - Terminate background processes

**Web & Network:**
- `WebSearch` - Search the web
- `WebFetch` - Fetch and analyze web content

**Task Management:**
- `TodoWrite` - Create and manage task lists
- `ExitPlanMode` - Exit planning mode when ready to code

The tools are designed to help with software engineering tasks like reading code, making changes, running tests, searching codebases, and managing complex multi-step tasks.
Result ended
Cost: $0.021489

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Prompt: Calculate 15 + 27
==================================================
Using tool: mcp__calc__add
  Input: {'a': '15', 'b': '27'}
Tool Result: <tool_use_error>Error: No such tool available: mcp__calc__add</tool_use_error>...
Claude: 42
Result ended
Cost: $0.012948

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Prompt: What is 100 divided by 7?
==================================================
Using tool: mcp__calc__divide
  Input: {'a': '100', 'b': '7'}
Tool Result: <tool_use_error>Error: No such tool available: mcp__calc__divide</tool_use_error>...
Claude: 14.285714285714286
Result ended
Cost: $0.012739

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Prompt: Calculate the square root of 144
==================================================
Using tool: mcp__calc__sqrt
  Input: {'number': '144'}
Tool Result: <tool_use_error>Error: No such tool available: mcp__calc__sqrt</tool_use_error>...
Claude: 12
Result ended
Cost: $0.012465

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Prompt: What is 2 raised to the power of 8?
==================================================
Claude: 256
Result ended
Cost: $0.006611

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Prompt: Calculate (12 + 8) * 3 - 10
==================================================
Claude: I'll calculate (12 + 8) * 3 - 10 step by step.
Using tool: mcp__calc__add
  Input: {'a': '12', 'b': '8'}
Tool Result: <tool_use_error>Error: No such tool available: mcp__calc__add</tool_use_error>...
Claude: (12 + 8) * 3 - 10 = 20 * 3 - 10 = 60 - 10 = 50
Result ended
Cost: $0.013793

It seems like the MCP tools are not registered.

[Riehantunut]

By using the latest commit the problem solved itself. Got error with latest published version.