Provider Errors

Errors for dependency injection, provider resolution, and scope management.

Overview

Provider errors are thrown by the FrontMCP dependency injection system. They cover unregistered providers, scope mismatches, construction failures, circular dependencies, and plugin dependency issues. All provider errors are internal errors.

Error Reference

ProviderNotRegisteredError

Thrown when a provider token is not found in the registry.

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

new ProviderNotRegisteredError(tokenName: string, context?: string)

Example:

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

throw new ProviderNotRegisteredError('DatabaseService', 'ToolRegistry');
// "Provider "DatabaseService" is not registered (ToolRegistry)"

---

ProviderScopeMismatchError

Thrown when a provider’s scope doesn’t match the registry it’s being resolved in.

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

new ProviderScopeMismatchError(tokenName: string, scopeName: string, registryName: string)

---

ProviderNotInstantiatedError

Thrown when a provider is expected to be instantiated but hasn’t been created yet.

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

new ProviderNotInstantiatedError(tokenName: string, scope?: string, context?: string)

---

DependencyCycleError

Thrown when a circular dependency is detected in the provider graph.

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

new DependencyCycleError(cycle: string)

Example:

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

throw new DependencyCycleError('A -> B -> C -> A');
// "Circular dependency detected: A -> B -> C -> A"

---

ProviderConstructionError

Thrown when constructing a provider instance fails.

Property	Type	Value
code	string	PROVIDER_CONSTRUCTION_FAILED
statusCode	number	500
isPublic	boolean	false
originalError	Error | undefined	The underlying cause

new ProviderConstructionError(tokenName: string, cause?: Error | string, qualifier?: string)

Example:

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

throw new ProviderConstructionError('DatabaseService', new Error('Connection refused'));
// "Failed to construct provider "DatabaseService": Connection refused"

---

ProviderDependencyError

Thrown when a provider dependency cannot be resolved.

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

new ProviderDependencyError(message: string)

---

ProviderScopedAccessError

Thrown when a scoped provider is accessed from the wrong scope.

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

new ProviderScopedAccessError(tokenName: string, scopeName: string)

Example:

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

throw new ProviderScopedAccessError('RequestLogger', 'global');
// "Cannot access scoped provider "RequestLogger" from scope "global""

---

ProviderNotAvailableError

Thrown when a provider is not available in the current context.

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

new ProviderNotAvailableError(tokenName: string, context?: string)

---

PluginDependencyError

Thrown when a plugin dependency cannot be resolved.

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

new PluginDependencyError(message: string)

---

InvalidDependencyScopeError

Thrown when a dependency has an invalid scope configuration.

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

new InvalidDependencyScopeError(message: string)

---

InvalidPluginScopeError

Thrown when a plugin with scope='server' is used in a standalone app, which is not allowed.

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

new InvalidPluginScopeError(message: string)