SMTP MCP Server

Instructions

Implementation Reference

• src/requestHandler.ts:179-215 (handler)

  Executes the send-bulk-emails tool: constructs BulkEmailData from tool parameters and delegates to the sendBulkEmails core function.
  async function handleSendBulkEmails(parameters: any) { try { // Prepare the bulk email data const bulkEmailData: BulkEmailData = { recipients: parameters.recipients, subject: parameters.subject, body: parameters.body, from: parameters.from, cc: parameters.cc, bcc: parameters.bcc, templateId: parameters.templateId, templateData: parameters.templateData, batchSize: parameters.batchSize, delayBetweenBatches: parameters.delayBetweenBatches }; // Send the bulk emails const result = await sendBulkEmails(bulkEmailData, parameters.smtpConfigId); return { success: result.success, totalSent: result.totalSent, totalFailed: result.totalFailed, failures: result.failures, message: result.message }; } catch (error) { logToFile('Error in handleSendBulkEmails:'); logToFile(error instanceof Error ? error.message : 'Unknown error'); return { success: false, totalSent: 0, totalFailed: parameters.recipients?.length || 0, message: error instanceof Error ? error.message : 'Unknown error' }; } }
• src/emailService.ts:231-318 (helper)

  Core bulk email sending logic: batches recipients, creates individual EmailData per recipient (with template personalization), sends via sendEmail, tracks stats and failures.
  export async function sendBulkEmails(data: BulkEmailData, smtpConfigId?: string): Promise<{ success: boolean; totalSent: number; totalFailed: number; failures?: { email: string; error: string }[]; message?: string; }> { try { const { recipients, batchSize = 10, delayBetweenBatches = 1000 } = data; if (!recipients || recipients.length === 0) { return { success: false, totalSent: 0, totalFailed: 0, message: 'No recipients provided' }; } const failures: { email: string; error: string }[] = []; let totalSent = 0; // Process recipients in batches for (let i = 0; i < recipients.length; i += batchSize) { const batch = recipients.slice(i, i + batchSize); // Send emails to the batch (one by one to allow for individual template processing) const promises = batch.map(async (recipient) => { try { // Create email data for single recipient using the bulk data const emailData: EmailData = { to: recipient, subject: data.subject, body: data.body, from: data.from, cc: data.cc, bcc: data.bcc, templateId: data.templateId, templateData: { ...data.templateData, email: recipient.email, name: recipient.name || '' } }; const result = await sendEmail(emailData, smtpConfigId); if (result.success) { totalSent++; return { success: true }; } else { failures.push({ email: recipient.email, error: result.message || 'Unknown error' }); return { success: false, error: result.message }; } } catch (error) { failures.push({ email: recipient.email, error: error instanceof Error ? error.message : 'Unknown error' }); return { success: false, error }; } }); await Promise.all(promises); // If not the last batch, wait before processing the next batch if (i + batchSize < recipients.length) { await new Promise(resolve => setTimeout(resolve, delayBetweenBatches)); } } return { success: totalSent > 0, totalSent, totalFailed: failures.length, failures: failures.length > 0 ? failures : undefined, message: `Successfully sent ${totalSent} out of ${recipients.length} emails` }; } catch (error) { logToFile(`Error sending bulk emails: ${error}`); return { success: false, totalSent: 0, totalFailed: data.recipients.length, message: error instanceof Error ? error.message : 'Unknown error sending bulk emails' }; } }
• src/tools.ts:95-176 (schema)

  Input schema and metadata definition for the send-bulk-emails tool.
  "send-bulk-emails": { name: "send-bulk-emails", description: "Send emails in bulk to multiple recipients with rate limiting", inputSchema: { type: "object", properties: { recipients: { type: "array", items: { type: "object", properties: { email: { type: "string" }, name: { type: "string" } }, required: ["email"] }, description: "Array of recipients" }, subject: { type: "string", description: "Email subject" }, body: { type: "string", description: "Email body (HTML supported)" }, from: { type: "object", properties: { email: { type: "string" }, name: { type: "string" } }, description: "Sender information. If not provided, the default SMTP user will be used." }, cc: { type: "array", items: { type: "object", properties: { email: { type: "string" }, name: { type: "string" } }, required: ["email"] }, description: "Array of CC recipients" }, bcc: { type: "array", items: { type: "object", properties: { email: { type: "string" }, name: { type: "string" } }, required: ["email"] }, description: "Array of BCC recipients" }, templateId: { type: "string", description: "ID of the email template to use. If not provided, the email will use the subject and body provided." }, templateData: { type: "object", description: "Data to be used for template variable substitution" }, batchSize: { type: "number", description: "Number of emails to send in each batch (default: 10)" }, delayBetweenBatches: { type: "number", description: "Delay between batches in milliseconds (default: 1000)" }, smtpConfigId: { type: "string", description: "ID of the SMTP configuration to use. If not provided, the default configuration will be used." } }, required: ["recipients", "subject", "body"] } },
• src/index.ts:59-62 (registration)

  Registers the send-bulk-emails tool (among others) by calling createToolDefinitions() and passing the tools record to setupRequestHandlers.
  const TOOLS = createToolDefinitions(); // Setup request handlers await setupRequestHandlers(server, TOOLS);