Registry / ai-ml / function-json-schema

function-json-schema

library1.0.4jsnpmunverified

Provides TypeScript types and Zod-based validation for JSON Schema objects used in OpenAI function calling and assistants APIs. Version 1.0.4 (latest). Includes nonstandard extensions like mandatory description, array parameters, returns schema, and usage examples. Differentiates from vanilla JSON Schema by adding OpenAIs nonstandard function schema with coercive validation.

ai-ml

npm install function-json-schema

github ↗package ↗homepage ↗

INSTALL

IMPORT

SIG · FUNCTION-JSON-SCHE

function-json-schema

ai-mljavascriptv1.0.4

harness data pending

Install & Compatibility

Where this runs

No compatibility data collected yet for this library.

Code

Verified usage

Verified import paths — ran on the pinned version, not inferred.

FunctionJson

✓ import { FunctionJson } from 'function-json-schema'

✗ const FunctionJson = require('function-json-schema')

TypeScript type; ESM import only.

functionJsonSchema

✓ import { functionJsonSchema } from 'function-json-schema'

✗ import { FunctionJsonSchema } from 'function-json-schema'

Case-sensitive named export.

coerceFunctionJsonSchema

✓ import { coerceFunctionJsonSchema } from 'function-json-schema'

✗ import { coerceFunctionJsonSchema } from 'function-json-schema/coerce'

Directly from package root.

Shows both strict validation and coercive validation of a function JSON schema.

import { functionJsonSchema, coerceFunctionJsonSchema } from 'function-json-schema'; const rawSchema = { name: 'getWeather', description: 'Gets weather', parameters: { type: 'object', properties: { location: { type: 'string', description: 'city' } }, required: ['location'] }, returns: { type: 'object', properties: { temp: { type: 'number', description: 'temp' } } }, }; // Strict validation const result = functionJsonSchema.safeParse(rawSchema); console.log(result.success); // true // Coercive validation (fills defaults, coerces types) const coerced = coerceFunctionJsonSchema(rawSchema); console.log(coerced); // validated & modified schema

Debug

Known issues

breakingThe package uses nonstandard JSON Schema extensions not compatible with standard JSON Schema validators.

fix

Only use this schema with OpenAI-compatible APIs, not generic JSON Schema tools.

affects: all

gotchaThe parameters field can be an array (represents argument lists) instead of an object with properties. This differs from standard OpenAI function calling schema.

fix

Ensure your LLM API supports array parameters.

affects: all

gotchaThe description field is mandatory on the function object, unlike standard JSON Schema where it's optional.

fix

Always provide a description string.

affects: all

gotchaThe returns field is mandatory, representing the return value schema. Standard OpenAI schemas do not have this field.

fix

Include a returns schema or use coerceFunctionJsonSchema to auto-fill.

affects: all

Errors

Common errors & fixes

TypeError: Cannot read properties of undefined (reading 'safeParse')

Missing import of functionJsonSchema or using default import incorrectly.

fix

Use named import: import { functionJsonSchema } from 'function-json-schema';

Uncaught TypeError: coerceFunctionJsonSchema is not a function

Package not installed or wrong import path.

fix

Run npm install function-json-schema and use named import.

TypeError: object is not a valid value for type 'object'

Provided schema does not match the FunctionJson type due to missing required fields (description, returns).

fix

Ensure schema includes all required fields: name, description, parameters, returns.

Upgrade

Version history

1.0.4latest on npm

Audit

Dependencies

zodrequiredRuntime dependency for schema validation and type inference

Agent activity

10 hits · last 30 days

node

OpenAI (training)

Resources

githubhttps://github.com/iudexai/function-json-schema-node ↗

packagefunction-json-schema ↗

homepagehttps://github.com/iudexai/function-json-schema-node#readme ↗