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b9153404f4* code mode * update uv.lock for monty optional dep 🤖 Generated with Claude Code * retry CI * Address PR review comments on CodeMode transform 🤖 Generated with Claude Code Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com> * Fix ty unresolved-attribute error on search_helper 🤖 Generated with Claude Code Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com> * more idiomacy * harden * fix docs * harden * fix red CI * Refactor CodeMode to use CatalogTransform base class Removes the duplicate ContextVar bypass pattern in favor of the shared CatalogTransform machinery. Also fixes a pre-existing bug where `from __future__ import annotations` caused NameError for Annotated in nested function scopes at runtime. * Remove redundant _get_visible_tools wrapper in CodeMode * Rewrite CodeMode docs with proper motivation and structure * Fix type narrowing in collision test * Stop unwrapping tool results in CodeMode's call_tool call_tool() inside execute blocks now returns structured content as-is, preserving the {"result": value} wrapping. This means the output schema shown in search results accurately describes what call_tool() returns, so LLMs can trust the schema when writing code. Also adds examples/code_mode/ with a server and narrated client demo. * Simplify call_tool return type: dict | str * Fix example client to unwrap structured results * Let server resolve tool versions instead of pinning first match * Rewrite CodeMode docs to match current behavior * Rename optional extra from monty to code-mode --------- Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com> Co-authored-by: Jeremiah Lowin <153965+jlowin@users.noreply.github.com>
84 lines
1.9 KiB
Python
84 lines
1.9 KiB
Python
"""Example: CodeMode transform — search and execute tools via code.
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CodeMode replaces the entire tool catalog with two meta-tools: `search`
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(keyword-based tool discovery) and `execute` (run Python code that chains
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tool calls in a sandbox). This dramatically reduces round-trips and
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context window usage when an LLM needs to orchestrate many tools.
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Requires pydantic-monty for the sandbox:
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pip install "fastmcp[code-mode]"
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Run with:
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uv run python examples/code_mode/server.py
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"""
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from fastmcp import FastMCP
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from fastmcp.experimental.transforms import CodeMode
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mcp = FastMCP("CodeMode Demo")
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@mcp.tool
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def add(a: int, b: int) -> int:
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"""Add two numbers together."""
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return a + b
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@mcp.tool
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def multiply(x: float, y: float) -> float:
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"""Multiply two numbers."""
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return x * y
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@mcp.tool
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def fibonacci(n: int) -> list[int]:
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"""Generate the first n Fibonacci numbers."""
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if n <= 0:
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return []
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seq = [0, 1]
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while len(seq) < n:
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seq.append(seq[-1] + seq[-2])
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return seq[:n]
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@mcp.tool
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def reverse_string(text: str) -> str:
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"""Reverse a string."""
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return text[::-1]
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@mcp.tool
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def word_count(text: str) -> int:
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"""Count the number of words in a text."""
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return len(text.split())
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@mcp.tool
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def to_uppercase(text: str) -> str:
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"""Convert text to uppercase."""
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return text.upper()
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@mcp.tool
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def list_files(directory: str) -> list[str]:
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"""List files in a directory."""
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import os
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return os.listdir(directory)
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@mcp.tool
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def read_file(path: str) -> str:
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"""Read the contents of a file."""
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with open(path) as f:
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return f.read()
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# CodeMode collapses all 8 tools into just `search` + `execute`.
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# The LLM discovers tools via keyword search, then writes Python
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# scripts that chain multiple tool calls in a single round-trip.
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mcp.add_transform(CodeMode())
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if __name__ == "__main__":
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mcp.run()
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