Standard Schema

toolschema implements the Standard Schema and Standard JSON Schema protocols for ecosystem interop.

Access

definition = schema(my_fn)
host = definition.standard

# Standard Schema protocol
standard = host["~standard"]

Protocol shape

{
    "version": 1,
    "vendor": "toolschema",
    "validate": <callable>,
    "jsonSchema": {
        "input": <callable>,
        "output": <callable>,
    },
}

JSON Schema export

from toolschema import JSONSchemaOptions

standard = definition.standard["~standard"]

input_schema = standard["jsonSchema"]["input"]()
output_schema = standard["jsonSchema"]["output"]()  # raises if no return type

# With options
opts = JSONSchemaOptions(target="draft-2020-12")
input_schema = standard["jsonSchema"]["input"](opts)

JSONSchemaOptions

Field	Type	Default	Description
target	"draft-2020-12" | "draft-07" | "openapi-3.0"	"draft-2020-12"	Schema dialect
library_options	dict | None	None	Reserved for future use

Validate via protocol

result = standard["validate"]({"city": "London"})

Same as definition.validate().

Why this matters

Libraries that support Standard Schema can consume toolschema tools without a custom adapter:

• Unified validate() interface
• Unified jsonSchema.input() / jsonSchema.output() export
• Aligns with Pre-PEP inspect.tool_schema direction

Pre-PEP alignment

See Pre-PEP alignment for how schema() and @tool map to the proposed stdlib API.