get_author_info

Instructions

Implementation Reference

• src/tools/get-author-info/index.ts:24-100 (handler)

  The handler function that parses arguments, fetches detailed author information from the Open Library API using the provided author_key, processes the bio if needed, and returns the data as JSON or an error message.

  const handleGetAuthorInfo = async (
    args: unknown,
    axiosInstance: AxiosInstance,
  ): Promise<CallToolResult> => {
    const parseResult = GetAuthorInfoArgsSchema.safeParse(args);
  
    if (!parseResult.success) {
      const errorMessages = parseResult.error.errors
        .map((e) => `${e.path.join(".")}: ${e.message}`)
        .join(", ");
      throw new McpError(
        ErrorCode.InvalidParams,
        `Invalid arguments for get_author_info: ${errorMessages}`,
      );
    }
  
    const authorKey = parseResult.data.author_key;
  
    try {
      const response = await axiosInstance.get<DetailedAuthorInfo>(
        `/authors/${authorKey}.json`,
      );
  
      if (!response.data) {
        // Should not happen if API returns 200, but good practice
        return {
          content: [
            {
              type: "text",
              text: `No data found for author key: "${authorKey}"`,
            },
          ],
        };
      }
  
      // Optionally format the bio if it's an object
      const authorData = { ...response.data };
      if (typeof authorData.bio === "object" && authorData.bio !== null) {
        // eslint-disable-next-line @typescript-eslint/no-explicit-any
        authorData.bio = (authorData.bio as any).value; // Adjust type assertion if needed
      }
  
      return {
        content: [
          {
            type: "text",
            // Return the full author details as JSON
            text: JSON.stringify(authorData, null, 2),
          },
        ],
      };
    } catch (error) {
      let errorMessage = `Failed to fetch author data for key ${authorKey}.`;
      if (axios.isAxiosError(error)) {
        if (error.response?.status === 404) {
          errorMessage = `Author with key "${authorKey}" not found.`;
        } else {
          errorMessage = `Open Library API error: ${
            error.response?.statusText ?? error.message
          }`;
        }
      } else if (error instanceof Error) {
        errorMessage = `Error processing request: ${error.message}`;
      }
      console.error(`Error in get_author_info (${authorKey}):`, error);
  
      return {
        content: [
          {
            type: "text",
            text: errorMessage,
          },
        ],
        isError: true,
      };
    }
  };

• src/tools/get-author-info/index.ts:11-19 (schema)

  Zod schema defining and validating the input parameter 'author_key' which must match the Open Library author key format (e.g., OL123A).

  // Schema for the get_author_info tool arguments
  export const GetAuthorInfoArgsSchema = z.object({
    author_key: z
      .string()
      .min(1, { message: "Author key cannot be empty" })
      .regex(/^OL\d+A$/, {
        message: "Author key must be in the format OL<number>A",
      }),
  });

• src/index.ts:83-98 (registration)

  Registration of the 'get_author_info' tool in the MCP server's list of tools, including name, description, and input schema for ListTools requests.

  {
    name: "get_author_info",
    description:
      "Get detailed information for a specific author using their Open Library Author Key (e.g. OL23919A).",
    inputSchema: {
      type: "object",
      properties: {
        author_key: {
          type: "string",
          description:
            "The Open Library key for the author (e.g., OL23919A).",
        },
      },
      required: ["author_key"],
    },
  },

• src/index.ts:174-175 (registration)

  Dispatch logic in the CallToolRequest handler that routes 'get_author_info' calls to the handleGetAuthorInfo function.

  case "get_author_info":
    return handleGetAuthorInfo(args, this.axiosInstance);

• src/tools/get-author-info/types.ts:2-27 (helper)

  TypeScript interface defining the structure of the detailed author information returned by the Open Library API.

  export interface DetailedAuthorInfo {
    name: string;
    personal_name?: string;
    birth_date?: string;
    death_date?: string;
    bio?: string | { type: string; value: string }; // Bio can be string or object
    alternate_names?: string[];
    links?: { title: string; url: string; type: { key: string } }[];
    photos?: number[]; // Array of cover IDs
    source_records?: string[];
    wikipedia?: string;
    key: string;
    remote_ids?: {
      amazon?: string;
      librarything?: string;
      viaf?: string;
      goodreads?: string;
      storygraph?: string;
      wikidata?: string;
      isni?: string;
    };
    latest_revision?: number;
    revision: number;
    created?: { type: string; value: string };
    last_modified: { type: string; value: string };
  }