Skip to content

isSealed

Static method on Object.

Returns true if existing property attributes cannot be modified in an object and new properties cannot be added to the object.

isSealed(input: { o: any; prompt?: string }): Promise<boolean>

The prompt field is optional. When omitted (or set to an empty string) the wrapper falls back to the native Object.isSealed and returns a resolved Promise without contacting the LLM. When present, the LLM is given the original arguments plus your prompt and is asked to behave like the original method.

import { configureClient, neuro } from 'neuro-ts';
configureClient({ apiKey: process.env.OPENAI_API_KEY });
// Sealed check. Structure locked, values free. The middle child nobody remembers correctly.
await neuro.object.isSealed({ o: schema, prompt: 'return true when no properties can be added or removed but values may still change - the in-between state constantly mistaken for frozen' });

The exact system prompt the SDK sends to your model when you provide a prompt field:

Generated promptObject.isSealed
You are simulating the JavaScript built-in `Object.isSealed`.
## Original signature(s)
  Overload 1: (o: any) => boolean
## JSDoc
Returns true if existing property attributes cannot be modified in an object and new properties cannot be added to the object.

## How to respond
- Behave EXACTLY as the original `isSealed` would, but use the user's intent to choose any callback / comparator / transform logic that the original would normally accept as an argument.
- Strictly preserve the original return type and shape.
- Output ONLY the JSON-encoded return value of the function call.
- Do NOT include explanations, prose, comments, or markdown fences.
- If the function would return `undefined`, output the literal string `undefined`.
- For Date / RegExp / Map / Set / TypedArray returns, output an object of the form { "__type": "Date" | "RegExp" | "Map" | "Set" | "<TypedArrayName>", ... } so the SDK can rehydrate it.