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🤖 AI & LLMs

Type instantiation is excessively deep and possibly infinite.

Freshabout 22 hours ago
Mar 14, 20260 views
Confidence Score74%
74%

Problem

When I use any of the new openai-function functionality in langchain, I get many kinds of errors on typescript and eslint also takes over 30 seconds to run. Specifically, when using the DynamicStructuredTool with this zod schema: [code block] This seems like a simple schema but somehow I get the error `Type instantiation is excessively deep and possibly infinite. Additionally, it is also giving me this error `Types have separate declarations of a private property  _cached`

Error Output

error `Type instantiation is excessively deep and possibly infinite.

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1 Fix

Canonical Fix
Unverified Fix
New Fix – Awaiting Verification

Refactor Zod Schema to Avoid Deep Type Instantiation

Medium Risk

The error 'Type instantiation is excessively deep and possibly infinite' occurs due to TypeScript's type system limitations when dealing with complex recursive types. In this case, the Zod schema may have recursive definitions or overly complex structures that lead to deep type instantiation. The error regarding '_cached' suggests that there are conflicting declarations of private properties, likely due to multiple instances of the same type being defined in a way that TypeScript cannot resolve.

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  1. 1

    Simplify Zod Schema

    Review and simplify the Zod schema to reduce complexity. Avoid deeply nested structures and recursive types where possible.

    typescript
    const schema = z.object({ name: z.string(), age: z.number() });
  2. 2

    Use Type Aliases

    Create type aliases for complex types to help TypeScript manage type instantiation better. This can prevent excessive depth in type checks.

    typescript
    type User = { name: string; age: number; }; const schema = z.object<User>({ name: z.string(), age: z.number() });
  3. 3

    Check for Recursive Types

    Examine the schema for any recursive types that may lead to infinite instantiation. If found, refactor them to use a more manageable structure.

    typescript
    // Example of avoiding recursion
    const schema = z.object({ parent: z.lazy(() => schema.optional()) });
  4. 4

    Update TypeScript and ESLint Configurations

    Ensure that your TypeScript and ESLint configurations are optimized for performance. Adjust the 'maxNodeModuleJsDepth' setting in tsconfig.json to limit the depth of type checks.

    json
    { "compilerOptions": { "maxNodeModuleJsDepth": 1 } }
  5. 5

    Test Changes

    Run TypeScript and ESLint after making changes to ensure that the errors are resolved and performance has improved.

    bash
    npm run lint && npm run build

Validation

Confirm that the TypeScript compiler no longer throws the 'excessively deep' error and that ESLint runs within an acceptable time frame (under 5 seconds). Additionally, ensure that the application functions as expected with the modified schema.

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Environment

Submitted by

AC

Alex Chen

2450 rep

Tags

langchainllmairag