Band MCP Server

Instructions

Implementation Reference

• src/comments/tool.ts:121-177 (handler)

  The handler function that implements the core logic for the 'get_comments' tool: resolves band_key and post_key from inputs or URL, fetches comments from BAND API, optionally filters by comment_key, and returns JSON-formatted response.

  export async function handleToolCall(
    band_key: string | undefined,
    post_key: string | undefined,
    sort?: string,
    url?: string
  ) {
    let resolvedBandKey = band_key ? band_key.trim() : undefined;
    let resolvedPostKey = post_key ? post_key.trim() : undefined;
    let targetCommentKey: string | undefined;
  
    if (url) {
      const parsed = parseBandUrl(url);
      if (!resolvedBandKey) resolvedBandKey = parsed.bandKey;
      if (!resolvedPostKey) resolvedPostKey = parsed.postKey;
      targetCommentKey = parsed.commentKey;
    }
  
    if (!resolvedBandKey || !resolvedPostKey) {
      throw new Error(
        "band_key and post_key are required unless a valid BAND url is provided.",
      );
    }
  
    const params: Record<string, unknown> = { band_key: resolvedBandKey, post_key: resolvedPostKey };
    if (sort) params.sort = sort;
  
    const commentsData = await bandApiClient.get<CommentsResponse>(
      "/v2/band/post/comments",
      params
    );
    let payload = commentsData;
  
    if (targetCommentKey) {
      const matched = commentsData.items.filter(
        (item) => item.comment_key === targetCommentKey,
      );
  
      if (matched.length === 0) {
        throw new Error(
          `Comment ${targetCommentKey} was not found in the retrieved page. Try fetching the comments without filtering or adjust pagination.`,
        );
      }
  
      payload = {
        ...commentsData,
        items: matched,
      };
    }
    return {
      content: [
        {
          type: "text",
          text: JSON.stringify(payload, null, 2),
        },
      ],
    };
  }

• src/comments/tool.ts:9-101 (schema)

  The ToolDefinition object defining the name, description, inputSchema, and outputSchema for the 'get_comments' tool.

  export const ToolDefinition: Tool = {
    name: "get_comments",
    description: "Get comments from a specific post in BAND.",
    inputSchema: {
      type: "object",
      properties: {
        band_key: {
          type: "string",
          title: "Band Key",
          description: "band identifier",
        },
        post_key: {
          type: "string",
          title: "Post Key",
          description: "post identifier",
        },
        sort: {
          type: "string",
          title: "Sort",
          description: "sort order for comments",
        },
        url: {
          type: "string",
          title: "Comment URL",
          description:
            "Full BAND URL to the post or comment (e.g., https://band.us/band/{band_key}/post/{post_key}?commentId={comment_key}).",
        },
      },
      anyOf: [
        { required: ["band_key", "post_key"] },
        { required: ["url"] },
      ],
    },
    outputSchema: {
      type: "object",
      properties: {
        result_code: {
          type: "number",
          description: "Result code",
        },
        result_data: {
          type: "object",
          description: "Result data",
          properties: {
            paging: {
              type: "object",
              description: "Paging information",
            },
            items: {
              type: "array",
              description: "List of comments",
              items: {
                type: "object",
                properties: {
                  comment_key: {
                    type: "string",
                    description: "comment identifier",
                  },
                  content: {
                    type: "string",
                    description: "comment content",
                  },
                  created_at: {
                    type: "number",
                    description: "comment created time",
                  },
                  author: {
                    type: "object",
                    description: "comment author",
                    properties: {
                      name: {
                        type: "string",
                        description: "author name",
                      },
                      description: {
                        type: "string",
                        description: "author description",
                      },
                      profile_image_url: {
                        type: "string",
                        description: "author profile image url",
                      },
                    },
                  },
                },
              },
            },
          },
        },
      },
      required: ["result_code", "result_data"],
    },
  };

• src/tools.ts:15-28 (registration)

  Registration of the 'get_comments' tool (imported as comments.ToolDefinition) in the central bandTools array exported for MCP tool setup.

  export const bandTools: Tool[] = [
    profile.ToolDefinition,
    bands.ToolDefinition,
    posts.ToolDefinition,
    post.ToolDefinition,
    comments.ToolDefinition,
    permissions.ToolDefinition,
    albums.ToolDefinition,
    photos.ToolDefinition,
    writeComment.ToolDefinition,
    writePost.ToolDefinition,
    removePost.ToolDefinition,
    removeComment.ToolDefinition,
  ];

• src/tools.ts:48-54 (registration)

  Switch case in the main handleToolCall dispatcher that routes calls to the 'get_comments' handler in the comments module.

  case "get_comments":
    return comments.handleToolCall(
      a.band_key as string | undefined,
      a.post_key as string | undefined,
      a.sort as string | undefined,
      a.url as string | undefined
    );