Klaviyo MCP Server

Implementation Reference

• src/tools/webhooks.js:36-69 (handler)

  Executes the tool logic: constructs Klaviyo webhook payload with endpoint and events (optionally profile), posts to /webhooks/ via klaviyoClient, returns result or error.

  async (params) => {
    try {
      const payload = {
        data: {
          type: "webhook",
          attributes: {
            endpoint: params.endpoint,
            events: params.events
          }
        }
      };
      
      if (params.profile_id) {
        payload.data.relationships = {
          profile: {
            data: {
              type: "profile",
              id: params.profile_id
            }
          }
        };
      }
      
      const result = await klaviyoClient.post('/webhooks/', payload);
      return {
        content: [{ type: "text", text: JSON.stringify(result, null, 2) }]
      };
    } catch (error) {
      return {
        content: [{ type: "text", text: `Error creating webhook: ${error.message}` }],
        isError: true
      };
    }
  },

• src/tools/webhooks.js:31-35 (schema)

  Zod schema for tool inputs: required URL endpoint and events array, optional profile_id.

  {
    endpoint: z.string().url().describe("URL endpoint for the webhook"),
    events: z.array(z.string()).describe("Events to subscribe to"),
    profile_id: z.string().optional().describe("Profile ID for authentication")
  },

• src/tools/webhooks.js:28-71 (registration)

  Registers the 'create_webhook' tool on the MCP server with name, input schema, handler function, and description.

  // Create webhook
  server.tool(
    "create_webhook",
    {
      endpoint: z.string().url().describe("URL endpoint for the webhook"),
      events: z.array(z.string()).describe("Events to subscribe to"),
      profile_id: z.string().optional().describe("Profile ID for authentication")
    },
    async (params) => {
      try {
        const payload = {
          data: {
            type: "webhook",
            attributes: {
              endpoint: params.endpoint,
              events: params.events
            }
          }
        };
        
        if (params.profile_id) {
          payload.data.relationships = {
            profile: {
              data: {
                type: "profile",
                id: params.profile_id
              }
            }
          };
        }
        
        const result = await klaviyoClient.post('/webhooks/', payload);
        return {
          content: [{ type: "text", text: JSON.stringify(result, null, 2) }]
        };
      } catch (error) {
        return {
          content: [{ type: "text", text: `Error creating webhook: ${error.message}` }],
          isError: true
        };
      }
    },
    { description: "Create a new webhook in Klaviyo" }
  );

• src/server.js:43-43 (registration)

  Invokes registerWebhookTools which includes the registration of 'create_webhook'.

  registerWebhookTools(server);