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f2006804d2
When a prompt function returned `mcp.types.PromptMessage` objects directly and was executed as a task, the result serialization failed with "'PromptMessage' object has no attribute 'to_mcp'". The task result converter was calling `.to_mcp()` on what it thought was a FastMCP wrapper type, but the import actually pulls in `mcp.types.PromptMessage` directly, which is already the final MCP type. Removed the unnecessary conversion. 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude <noreply@anthropic.com>
57 lines
2 KiB
Python
57 lines
2 KiB
Python
"""Test prompt task with mcp.types.PromptMessage return values.
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Regression test for: PromptMessage object has no attribute 'to_mcp'
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"""
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import mcp.types
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from fastmcp import FastMCP
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from fastmcp.client import Client
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async def test_prompt_task_with_mcp_prompt_message():
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"""Prompt task returning mcp.types.PromptMessage should serialize correctly."""
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mcp_server = FastMCP("test")
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@mcp_server.prompt(task=True)
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async def greeting(name: str) -> list[mcp.types.PromptMessage]:
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return [
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mcp.types.PromptMessage(
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role="user",
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content=mcp.types.TextContent(type="text", text=f"Hello {name}"),
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)
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]
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async with Client(mcp_server) as client:
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task = await client.get_prompt("greeting", {"name": "World"}, task=True)
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result = await task.result()
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assert "Hello World" in result.messages[0].content.text # type: ignore[attr-defined]
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async def test_prompt_task_with_multiple_mcp_prompt_messages():
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"""Prompt task returning multiple mcp.types.PromptMessage objects."""
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mcp_server = FastMCP("test")
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@mcp_server.prompt(task=True)
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async def conversation(topic: str) -> list[mcp.types.PromptMessage]:
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return [
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mcp.types.PromptMessage(
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role="user",
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content=mcp.types.TextContent(
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type="text", text=f"Tell me about {topic}"
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),
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),
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mcp.types.PromptMessage(
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role="assistant",
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content=mcp.types.TextContent(
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type="text", text=f"{topic} is fascinating!"
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),
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),
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]
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async with Client(mcp_server) as client:
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task = await client.get_prompt("conversation", {"topic": "space"}, task=True)
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result = await task.result()
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assert len(result.messages) == 2
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assert "Tell me about space" in result.messages[0].content.text # type: ignore[attr-defined]
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assert "space is fascinating" in result.messages[1].content.text # type: ignore[attr-defined]
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