Normalization Errors

Errors for invalid provider and entity definitions during normalization.

Overview

Normalization errors are thrown during the normalization phase when provider or entity definitions have invalid shapes. This phase converts raw decorator metadata into normalized internal records. All normalization errors are internal errors.

Error Reference

MissingProvideError

Thrown when a provider/entity definition is missing the provide token.

Property	Type	Value
code	string	MISSING_PROVIDE
statusCode	number	500
isPublic	boolean	false

new MissingProvideError(entityType: string, name: string)

Example:

import { MissingProvideError } from '@frontmcp/sdk';

throw new MissingProvideError('Provider', 'DatabaseService');
// "Provider 'DatabaseService' is missing 'provide'."

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InvalidUseClassError

Thrown when useClass on a provider/entity is not a valid class (constructor function).

Property	Type	Value
code	string	INVALID_USE_CLASS
statusCode	number	500
isPublic	boolean	false

new InvalidUseClassError(entityType: string, tokenName: string)

Example:

import { InvalidUseClassError } from '@frontmcp/sdk';

throw new InvalidUseClassError('Provider', 'DatabaseService');
// "'useClass' on Provider 'DatabaseService' must be a class."

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InvalidUseFactoryError

Thrown when useFactory on a provider/entity is not a function.

Property	Type	Value
code	string	INVALID_USE_FACTORY
statusCode	number	500
isPublic	boolean	false

new InvalidUseFactoryError(entityType: string, tokenName: string)

Example:

import { InvalidUseFactoryError } from '@frontmcp/sdk';

throw new InvalidUseFactoryError('Provider', 'ConfigService');
// "'useFactory' on Provider 'ConfigService' must be a function."

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InvalidUseValueError

Thrown when useValue on a provider/entity is undefined.

Property	Type	Value
code	string	INVALID_USE_VALUE
statusCode	number	500
isPublic	boolean	false

new InvalidUseValueError(entityType: string, tokenName: string)

Example:

import { InvalidUseValueError } from '@frontmcp/sdk';

throw new InvalidUseValueError('Provider', 'API_KEY');
// "'useValue' on Provider 'API_KEY' must be defined."

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InvalidEntityError

Thrown when an entity (tool, resource, adapter, etc.) has an invalid shape.

Property	Type	Value
code	string	INVALID_ENTITY
statusCode	number	500
isPublic	boolean	false

new InvalidEntityError(entityType: string, name: string, expected: string)

Example:

import { InvalidEntityError } from '@frontmcp/sdk';

throw new InvalidEntityError('Tool', 'my_tool', 'a class extending ToolContext');
// "Invalid Tool 'my_tool'. Expected a class extending ToolContext."