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bbf3050ba7- Restructured confusing sections: 'Object-like Results' → 'Dictionaries and Objects', 'Non-object Results' → 'Primitives and Collections', 'Complex Type Example' → 'Typed Models' - Simplified CodeGroup examples to show Tool Definition + MCP Result instead of 3-4 confusing tabs - Split Primitives/Collections into separate CodeGroups for clarity - Renamed 'Full Control with ToolResult' → 'ToolResult and Metadata' for better TOC visibility - Flattened ToolResult documentation with inline field descriptions instead of nested headings - Added version badge for ToolResult meta field (2.13.1) - Added clarification that ToolResult meta is separate from @mcp.tool meta - Improved example server with realistic metadata (execution time, character/word counts) - Fixed code formatting (multi-line objects, trailing commas)
41 lines
956 B
Python
41 lines
956 B
Python
"""
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FastMCP Echo Server with Metadata
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Demonstrates how to return metadata alongside content and structured data.
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The meta field can include execution details, versioning, or other information
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that clients may find useful.
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"""
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import time
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from dataclasses import dataclass
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from fastmcp import FastMCP
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from fastmcp.tools.tool import ToolResult
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mcp = FastMCP("Echo Server")
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@dataclass
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class EchoData:
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data: str
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length: int
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@mcp.tool
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def echo(text: str) -> ToolResult:
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"""Echo text back with metadata about the operation."""
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start = time.perf_counter()
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result = EchoData(data=text, length=len(text))
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execution_time = (time.perf_counter() - start) * 1000
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return ToolResult(
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content=f"Echoed: {text}",
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structured_content=result,
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meta={
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"execution_time_ms": round(execution_time, 2),
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"character_count": len(text),
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"word_count": len(text.split()),
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},
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)
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