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Multi-provider

false200/toolschema

Tutorial 4: Multi-provider export from one function¶

Time: 10 minutes
Prerequisites: Tutorial 1

One Python function. Four provider formats. Zero rewrites.

The function¶

from typing import Annotated
from toolschema import Field, schema, tool


@tool
def book_flight(
    origin: Annotated[str, Field(description="IATA code", pattern=r"^[A-Z]{3}$")],
    destination: Annotated[str, Field(description="IATA code", pattern=r"^[A-Z]{3}$")],
    passengers: Annotated[int, Field(ge=1, le=9)] = 1,
) -> dict:
    """Book a one-way flight."""
    return {"confirmation": "TS-12345", "origin": origin, "destination": destination}

Export all formats¶

definition = schema(book_flight)

openai = definition.to_openai()
openai_strict = definition.to_openai(strict=True)
mcp = definition.to_mcp()              # inline_refs=True by default (no $ref)
anthropic = definition.to_anthropic()  # constraints → description text
gemini = definition.to_gemini()        # STRING, INTEGER, OBJECT types

CLI batch export¶

uv run toolschema inspect myapp.tools:book_flight --format openai,mcp,anthropic,gemini
uv run toolschema export myapp.tools --output tools.json

OpenAI Agents SDK¶

from toolschema.integrations.openai_agents import to_agents_function_tool

agents_tool = to_agents_function_tool(definition, book_flight)
# agents_tool.params_json_schema matches definition.to_openai() parameters

Pydantic AI descriptor¶

from toolschema.integrations.pydantic_ai import to_pydantic_ai_tool

descriptor = to_pydantic_ai_tool(definition, book_flight)
# descriptor["parameters_json_schema"] ready for pydantic-ai registration

Run the example¶

uv run python examples/04_multi_provider.py

Provider differences (intentional)¶

Provider	Key difference
OpenAI strict	All properties required; `additionalProperties: false`
MCP	camelCase `inputSchema`; `$ref` inlined by default
Anthropic	`minLength`/`pattern` moved into description text
Gemini	Uppercase type names (`STRING`, `INTEGER`)

See provider quirks for details.

Next steps¶