PubChem MCP Server

/** * @fileoverview Handles the registration of the `pubchem_get_compound_image` tool. * @module src/mcp-server/tools/getCompoundImageUrl/registration */ import { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js"; import type { CallToolResult } from "@modelcontextprotocol/sdk/types.js"; import { BaseErrorCode, McpError } from "../../../types-global/errors.js"; import { ErrorHandler, logger, requestContextService, } from "../../../utils/index.js"; import { PubchemGetCompoundImageInput, PubchemGetCompoundImageInputSchema, pubchemGetCompoundImageLogic, } from "./logic.js"; /** * Registers the 'pubchem_get_compound_image' tool with the MCP server. * This tool fetches a 2D image of a compound's structure and returns it as a binary blob. * * @param {McpServer} server - The MCP server instance to register the tool with. */ export const registerPubchemGetCompoundImageTool = async ( server: McpServer, ): Promise<void> => { const toolName = "pubchem_get_compound_image"; const toolDescription = "Fetches a 2D image of a compound's structure for a given PubChem CID and returns the raw image data as a binary blob. Ideal for displaying chemical structures directly."; server.tool( toolName, toolDescription, PubchemGetCompoundImageInputSchema.shape, async ( params: PubchemGetCompoundImageInput, mcpContext: any, ): Promise<CallToolResult> => { const handlerContext = requestContextService.createRequestContext({ operation: "HandleToolRequest", toolName, mcpToolContext: mcpContext, input: params, }); try { logger.info( `Initiating tool request for ${toolName} for CID: ${params.cid}`, handlerContext, ); const result = await pubchemGetCompoundImageLogic( params, handlerContext, ); return { content: [ { type: "image", data: result.blob.toString("base64"), mimeType: result.mimeType, }, ], isError: false, }; } catch (error) { const handledError = ErrorHandler.handleError(error, { operation: "pubchemGetCompoundImageToolHandler", context: handlerContext, input: params, }); const mcpError = handledError instanceof McpError ? handledError : new McpError( BaseErrorCode.INTERNAL_ERROR, "An unexpected error occurred while fetching the compound image.", { originalErrorName: handledError.name }, ); logger.error(`Error in ${toolName} handler`, { ...handlerContext, error: mcpError, }); return { content: [ { type: "text", text: JSON.stringify({ error: { code: mcpError.code, message: mcpError.message, details: mcpError.details, }, }), }, ], isError: true, }; } }, ); };