Resource Errors

Overview

Resource errors cover failures related to MCP resources — not found, read failures, and invalid URIs. ResourceNotFoundError includes a custom toJsonRpcError() method that returns an MCP-compliant JSON-RPC error with the resource URI.

Error Reference

ResourceNotFoundError

Thrown when a requested resource URI does not match any registered resource.

Property	Type	Value
`code`	`string`	`RESOURCE_NOT_FOUND`
`statusCode`	`number`	`404`
`isPublic`	`boolean`	`true`
`uri`	`string`	The requested URI
`mcpErrorCode`	`number`	`-32002`

new ResourceNotFoundError(uri: string)

JSON-RPC format:

error.toJsonRpcError();
// { code: -32002, message: "Resource not found: file:///missing.txt", data: { uri: "file:///missing.txt" } }

Example:

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

throw new ResourceNotFoundError('file:///missing.txt');

ResourceReadError

Thrown when reading a resource fails. This is an internal error — details are hidden from clients. A public error thrown from execute() or passed to this.fail(), such as ResourceNotFoundError, is not wrapped.

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

new ResourceReadError(uri: string, originalError?: Error)

Example:

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

try {
  const data = await fs.readFile(path);
} catch (error) {
  throw new ResourceReadError('file:///data.json', error);
}

InvalidResourceUriError

Thrown when a resource URI does not conform to RFC 3986 or is otherwise malformed.

Property	Type	Value
`code`	`string`	`INVALID_RESOURCE_URI`
`statusCode`	`number`	`400`
`isPublic`	`boolean`	`true`

new InvalidResourceUriError(uri: string, reason?: string)

Example:

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

throw new InvalidResourceUriError('no-scheme', 'URI must have a valid scheme');

Decorators

API

Errors

Overview

Error Reference

ResourceNotFoundError

ResourceReadError

InvalidResourceUriError

​Overview

​Error Reference

​ResourceNotFoundError

​ResourceReadError

​InvalidResourceUriError

Overview

Error Reference

ResourceNotFoundError

ResourceReadError

InvalidResourceUriError