/**
* Base class for MCP prompt templates
*/
import type { PromptDefinition, PromptMessage, PromptResult } from './types.js';
/**
* Abstract base class for all prompt templates
*
* Prompt templates generate multi-message conversations for common workflows,
* orchestrating multiple tools and resources.
*/
export abstract class BasePrompt {
/** Unique identifier for the prompt */
abstract readonly name: string;
/** Human-readable description of what the prompt does */
abstract readonly description: string;
/** Optional list of arguments the prompt accepts */
abstract readonly arguments: Array<{
name: string;
description: string;
required: boolean;
}>;
/**
* Get the prompt definition for MCP ListPrompts response
*/
getDefinition(): PromptDefinition {
return {
name: this.name,
description: this.description,
arguments: this.arguments.length > 0 ? this.arguments : undefined,
};
}
/**
* Generate the prompt messages based on provided arguments
*
* @param args - Arguments provided by the client
* @returns Promise resolving to prompt result with messages
* @throws Error if required arguments are missing or invalid
*/
abstract generate(args: Record<string, string>): Promise<PromptResult>;
/**
* Validate that all required arguments are provided
*
* @param args - Arguments to validate
* @throws Error if validation fails
*/
protected validateArguments(args: Record<string, string>): void {
const requiredArgs = this.arguments.filter(arg => arg.required);
for (const arg of requiredArgs) {
if (!(arg.name in args) || args[arg.name] === undefined || args[arg.name] === '') {
throw new Error(`Required argument '${arg.name}' is missing`);
}
}
}
/**
* Helper to create a user message
*/
protected createUserMessage(text: string): PromptMessage {
return {
role: 'user',
content: {
type: 'text',
text,
},
};
}
/**
* Helper to create an assistant message
*/
protected createAssistantMessage(text: string): PromptMessage {
return {
role: 'assistant',
content: {
type: 'text',
text,
},
};
}
}
