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🔁 JSON Schema to Tool Definition

Convert a pasted JSON Schema object into provider-specific tool definitions with typed path errors, warnings, and copyable JSON summaries.

Conversion checks · Supported subset · utilito.schema-contract.v1
  • Validates pasted JSON, root object shape, properties, required fields, enum arrays, descriptions, and nested items.
  • Preserves descriptions, required fields, enums, additionalProperties, and nested schema nodes in the output wrapper.
  • Emits OpenAI, Anthropic, or MCP wrapper formats from one deterministic core.
  • Warns when $ref, oneOf, anyOf, or allOf may need provider-specific simplification.
Tool-calling contract workflow
Step 2: definition conversion. Use this when a JSON Schema already exists; start with Tool Schema Generator if you need to draft the schema first, then verify generated wrappers in Tool Calling Validator.
The conversion keeps agent discoverability intact by preserving descriptions, required inputs, and deterministic JSON summaries that can appear in API docs, manifests, or runtime tests.
 Runs in your browser
JSON Schema conversion runs locally in your browser. Shared links only include schema text when you explicitly opt in.
What this tool does
JSON Schema to Tool Definition converts an existing JSON Schema object into OpenAI, Anthropic, or MCP tool-definition wrappers.
Why it is useful
It helps AI developers reuse existing validation schemas while preserving descriptions, required fields, enums, and nested object structure for agent tools.
How it works
The browser parses and validates the pasted schema, reports path-specific issues, then wraps the schema in the selected provider format.
Best input
Use a clean root object schema with clear property descriptions, required fields, and simple enum/type constraints.
Agent tip
Provider support for advanced JSON Schema features varies; simplify complex refs and combiners before using a schema for model tool calling.
Privacy note
Schema conversion happens locally in your browser.
Important limitation
Provider tool-definition formats differ, and not every JSON Schema feature is supported by every model API or client SDK.
Quick answers
Can every schema become a tool?
No. Some constructs such as refs, oneOf, anyOf, and deeply nested dynamic objects may need simplification.
Should descriptions be detailed?
Yes. Good field descriptions improve correct tool selection and argument filling.
Common Use Cases
Wrap an existing validation schema
Paste a JSON Schema from your app and convert it into an OpenAI, Anthropic, or MCP tool wrapper.
Find required-field mismatches
Catch required fields that are missing from properties before a model or runtime sees the tool definition.
Compare provider output formats
Switch between OpenAI, Anthropic, and MCP wrappers while preserving the same input schema.
Agent MCP and tool schema workflow
Draft MCP client config, generate tool schemas, convert JSON Schema into provider tool definitions, and validate tool-call payloads before wiring an agent.
🔌MCP Config Generator🛠️Tool Schema Generator✅Tool Calling Validator✅JSON Schema Validator🔄Schema Converter🧰Context Workbench
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