mcp-claude-hackernews

Instructions

Implementation Reference

• index.ts:208-225 (registration)

  Registration of the hn_comments tool including its name, description, and input schema in the ListToolsRequestSchema handler.

  {
    name: "hn_comments",
    description: "Get comments for a story (by story ID or index from last story list)",
    inputSchema: {
      type: "object",
      properties: {
        story_id: {
          type: "number",
          description: "The ID of the story to get comments for"
        },
        story_index: {
          type: "number",
          description: "The index (1-based) of the story from the last fetched list",
          minimum: 1
        }
      }
    }
  }

• index.ts:329-383 (handler)

  The handler logic for hn_comments tool call, which resolves story ID, fetches story and comments, formats them, and returns text content.

  if (name === "hn_comments") {
    const storyId = typeof args?.story_id === 'number' ? args.story_id : NaN;
    const storyIndex = typeof args?.story_index === 'number' ? args.story_index : NaN;
  
    if (isNaN(storyId) && isNaN(storyIndex)) {
      throw new Error('Either a story ID or a story index is required');
    }
  
    let targetStoryId: number;
    if (!isNaN(storyId)) {
      targetStoryId = storyId;
    } else if (!isNaN(storyIndex) && storyIndex > 0 && storyIndex <= lastStoriesList.length) {
      targetStoryId = lastStoriesList[storyIndex - 1].id;
    } else {
      throw new Error('Invalid story index or ID provided');
    }
  
    if (isNaN(targetStoryId)) {
      throw new Error('Story ID must be a number');
    }
  
    const story = await api.getItemDetails(targetStoryId) as Story | null;
    if (!story) {
      throw new Error(`Story with ID ${targetStoryId} not found`);
    }
  
    if (!story.kids || story.kids.length === 0) {
      return {
        content: [
          {
            type: "text",
            text: `No comments found for story "${story.title}" (ID: ${story.id})`
          }
        ]
      };
    }
  
    const comments = await api.getComments(story.kids);
    const formattedComments = comments.map(comment => ({
      id: comment.id,
      by: comment.by,
      time: api.formatTime(comment.time),
      text: api.cleanText(comment.text),
      replies: comment.kids ? comment.kids.length : 0
    }));
  
    return {
      content: [
        {
          type: "text",
          text: formatCommentsAsText(story.title, formattedComments)
        }
      ]
    };
  }

• index.ts:97-109 (helper)

  Helper method in HackerNewsAPI to fetch multiple comments by their IDs.

  async getComments(commentIds: number[] = []): Promise<Comment[]> {
    if (!commentIds || commentIds.length === 0) {
      return [];
    }
    try {
      const commentPromises = commentIds.map(id => this.getItemDetails(id));
      const comments = await Promise.all(commentPromises);
      return comments.filter((comment): comment is Comment => comment !== null);
    } catch (error) {
      console.error('Failed to load comments:', error);
      return [];
    }
  }

• index.ts:428-443 (helper)

  Helper function to format the story title and list of comments into a readable text output.

  function formatCommentsAsText(storyTitle: string, comments: FormattedComment[]): string {
    if (!comments || comments.length === 0) {
      return "No comments found.";
    }
    
    const header = `Comments for "${storyTitle}" (Total: ${comments.length}):\n`;
    
    const formattedComments = comments.map((comment, index) => {
      return `${index + 1}. Comment by ${comment.by} at ${comment.time}:
     "${comment.text}"
     ${comment.replies > 0 ? `(${comment.replies} replies)` : '(no replies)'}
     ------------------------------`;
    }).join('\n\n');
    
    return header + '\n' + formattedComments;
  }

• index.ts:214-223 (schema)

  Input schema definition for hn_comments tool parameters.

    story_id: {
      type: "number",
      description: "The ID of the story to get comments for"
    },
    story_index: {
      type: "number",
      description: "The index (1-based) of the story from the last fetched list",
      minimum: 1
    }
  }