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Twilio
Cloud communications platform providing APIs and services for messaging, voice, email, authentication, and customer engagement.
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Twilio’s 2026 Heightened Awareness Period: Ensuring Reliable Messaging for Peak Season
Twilio has scheduled two 2026 Heightened Awareness Periods (HAPs) to manage messaging throughput during U.S. midterm election traffic and the Black Friday/Cyber Monday and holiday shopping surge. During these windows, high-volume short code and toll-free traffic shifts temporarily to Market Throughput, while 10DLC remains on Account-Based Throughput and RCS uses standard per-sender limits; contracted limits are honored. Most users need no action, but election senders should contact their account team by October 1, 2026, and holiday senders face deadlines for RCS approval, throughput review, A2P 10DLC requests, and supplementary orders. The election HAP runs November 2–4, 2026, while the holiday HAP runs November 19, 2026, through January 4, 2027; capacity is limited and allocated first come, first served.
On-Demand Masked Sessions with Twilio Proxy, Voice and Serverless
This tutorial presents a Just-in-Time (JIT) masked session workflow for securely connecting callers when phone numbers cannot be pre-associated because of inventory constraints. The design routes an inbound call to a reserved Twilio number through Twilio Voice, uses an IVR to collect a six-digit tracking code, and dynamically creates a private Twilio Proxy session. It uses five serverless endpoints plus helper functions; because the Out-of-Session Callback lacks keypad digits, a “2-Bounce” flow uses a redirect and a temporary Twilio Sync Document keyed by res- plus CallSid to carry the resolved destination, with a short TTL such as 900 seconds. On the second bounce, the destination is retrieved and deleted, and Proxy receives instructions to auto-create the session and bridge the caller. The result is an on-demand masked connection across standard cellular connections that avoids static phone-number preallocation and preserves the number pool.
How to Orchestrate Multi-Call Conversations with an LLM and Twilio Conversation Memory
The tutorial builds a C# .NET 9 ASP.NET Core voice service that preserves caller context, preferences, and action history across separate inbound calls. It combines Twilio Conversation Relay and a Twilio Conversation Memory Store with an OpenAI gpt-4o-mini service, using WebSockets to connect the call flow and stream generated text. The setup covers creating the project, installing Twilio, DotNetEnv, and OpenAI packages, configuring credentials and IDs in .env, exposing local webhooks with ngrok, and routing /voice to /ws. The sample assistant is framed as Owlbert's Auto Repair and is instructed to speak naturally, avoid lists and emojis, refer to caller details, and acknowledge uncertainty rather than guess. Testing uses two calls from the same number; the expected result is that the second call recalls first-call details and that Twilio shows a stored conversation summary.
What is CIAM in 2026 and why does it matter?
CIAM has expanded beyond password storage and login-time credential checks as digital experiences include autonomous AI agents and attacks make point-in-time verification less reliable. Modern customer identity is presented as a continuous trust and control layer across web, mobile, messaging, voice, email, and AI interactions, balancing low friction with adaptive risk detection. The architecture separates an identity authority, which owns identity, federation, and authorization, from a trust orchestration layer that evaluates live signals, triggers step-up verification, adapts to mid-session risk, and records decisions. It also must define delegated authority for agents, human approval boundaries, multi-signal decisioning, explainability, consent, and identity resolution. Twilio is described as an adjacent execution layer providing Verify, Lookup, carrier intelligence, device fingerprinting, and passwordless or one-time passcode flows for high-risk moments.
How to Connect Your Twilio Agent to External APIs
This tutorial shows how to connect a Twilio voice agent to an external REST API so it can retrieve live information during a conversation. It uses C# .NET 9, Twilio Conversation Relay, WebSockets, OpenAI tool calling, and the authentication-free Cat Facts API as a demonstration. An ASP.NET Core application exposes a /voice webhook, connects calls to a /ws endpoint, maintains conversation messages, streams model responses, and executes get_cat_fact by requesting and parsing JSON from the Cat Facts service. The guide also covers environment variables, NuGet dependencies, ngrok tunneling, Twilio number configuration, and troubleshooting for webhook URLs and API keys. After setup, callers can ask for a cat fact and receive one from the external service, illustrating how function tools can give voice agents real-time data and perform API-backed work.
How to Orchestrate Multi-Call Conversations with an LLM and Twilio Conversation Memory in Python
The tutorial builds a Python FastAPI voice service that preserves caller context, preferences, and action history across separate inbound calls using Twilio Conversation Memory. It connects a Twilio phone number to a /voice webhook and /ws WebSocket through Conversation Relay, then uses an asynchronous OpenAI client with gpt-4o-mini to generate streamed responses. A memory service retrieves stored information by caller number, while each completed call is summarized and written back to the configured memory store. The example uses an auto-repair assistant whose system prompt incorporates prior context before the next call, and the test procedure checks that a second call recalls details from the first. The setup requires Python 3.11 or later, Twilio and OpenAI credentials, a memory-store and configuration ID, and ngrok for exposing local webhooks.
How to Connect Your Twilio Agent to External APIs in Node.js
Voice agents can converse, but they need external APIs to retrieve live information or take actions such as checking inventory or booking appointments. This tutorial builds a Node.js voice agent with Twilio Conversation Relay, Express, WebSockets, and the OpenAI Node.js SDK. A Conversation Relay WebSocket handler collects voice prompts, maintains conversation messages, streams model output back to the call, and defines a get_cat_fact tool that fetches JSON from the unauthenticated Cat Facts REST API. The service returns the fetched fact or an error message, while TwiML connects Twilio's voice-capable number to the WebSocket endpoint. Testing uses Node.js 18+, an OpenAI API key, ngrok, and a POST /voice webhook; the stated result is that callers can ask for a cat fact and hear the API response.
How to Orchestrate Multi-Call Conversations with an LLM and Twilio Conversation in Node.js Memory
Disconnected voice calls can force callers to repeat information, creating friction for AI phone agents. It builds a Node.js Express service that preserves caller context, preferences, and action history across separate inbound calls using Twilio Conversation Memory. The implementation uses Express and express-ws for HTTP and WebSocket handling, the OpenAI SDK with gpt-4o-mini for streamed responses and summaries, and axios for Twilio’s Conversation Memory REST API; a memory store ID and other credentials are configured through environment variables. The sample application connects Twilio’s Conversation Relay to an auto-repair assistant, retrieves prior context for recognized callers, and logs a summary when a call ends. Testing involves two calls from the same phone number to verify that the second call recalls details from the first.
Italy's email open tracking pixels rules are changing
Italy’s data protection authority, the Garante per la protezione dei dati personali, has issued guidelines governing tracking pixels in email communications. The guidance says recipients must be told about tracking pixels regardless of the email’s purpose or sender, and that prior consent is required for many uses. Senders must comply by October 28, 2026; existing subscribers who signed up before April 29, 2026 need an opt-out opportunity, while subscribers from April 29 onward require prior, explicit consent for open tracking pixels. The guidance also includes complexities, including exemptions for some email types and different rules for opaque pixels, so senders are advised to review opt-in processes with legal or privacy teams. The change follows France’s earlier rules and may foreshadow similar action elsewhere in Europe.
How to Connect Your Twilio Agent to External APIs in Python
Voice agents can converse, but need external APIs to retrieve live data or take actions such as checking inventory and booking appointments. This tutorial builds a Python and FastAPI voice agent with Twilio Conversation Relay, OpenAI tool calling, and an unauthenticated Cat Facts REST API. A FastAPI webhook returns TwiML that connects callers to a websocket, while Conversation Relay messages are converted into conversation history and streamed responses. When the model requests a cat fact, the application executes the tool, sends its result back to OpenAI, and streams the follow-up answer to the caller. The setup uses environment variables for the OpenAI key, httpx for asynchronous external requests, and ngrok to expose local webhooks; the completed test lets a caller ask for and receive a cat fact.
How to Connect Your Twilio Agent to External APIs with PHP
The tutorial shows how to connect a Twilio voice agent to external REST APIs so an LLM-driven conversation can retrieve live information or support actions such as checking inventory or booking appointments. It builds the example in PHP 8.5 or later with OpenSwoole, Twilio Conversation Relay, OpenAI, and a WebSocket server, using Cat Facts as an unauthenticated API. The application exposes a POST /voice webhook that returns TwiML and connects Conversation Relay to a wss /ws endpoint, while session handling passes caller prompts into the OpenAI service. Tool calling routes the request to the Cat Facts endpoint, parses the JSON fact field, and returns either the fact, “No fact returned.”, or an error when the API response is unsuccessful or unavailable. Testing requires running php server.php, exposing port 8080 with ngrok, and configuring the Twilio number’s incoming webhook to /voice; the conclusion says external HTTP endpoints give agents real-time data.
How to Orchestrate Multi-Call Conversations with an LLM and Twilio Conversation Memory with PHP
This tutorial shows how to build a PHP voice agent that retains caller context, preferences, and action history across separate inbound calls. It uses Twilio Conversation Memory with a Memory Store, an Open Swoole service, Twilio ConversationRelay, and an OpenAI integration using gpt-4o-mini; the example models an auto-repair shop assistant. The OpenAI service appends supplied prior customer context to its system prompt, while streamed responses are sent through a WebSocket and environment variables provide API credentials and the Memory Store ID. After running the service on port 9501, exposing it with ngrok, and configuring the phone-number webhook, the tutorial tests two calls from the same number and says the second call should remember details from the first.
[Webinar] Elevating customer engagement with WhatsApp
The webinar examines how businesses can use WhatsApp for secure account verification, one-time passcodes, operational alerts, and customer conversations. It presents notification overload, third-party portals, single-use apps, and unbranded sender numbers as reasons critical messages may be ignored, affecting deliveries and transactions. Speakers from Twilio, WhatsApp, and Orbio AI describe a verified, two-way model built around WhatsApp Utility messaging, interactive buttons, logic flows, end-to-end encryption, and visual drag-and-drop automation. Orbio AI's examples include screening candidates, scheduling interviews, reminders, onboarding, and engagement conversations for enterprise clients while the webinar claims improved deliverability, faster user action, reduced manual work, protection against SMS toll fraud, and scalable deployment. It also positions app-based delivery over WiFi and cellular networks as a more reliable alternative.
What Is SMS Pumping Fraud and How to Stop It
SMS pumping fraud, also called SMS toll fraud, uses bots and fake phone numbers to trigger automated text messages from public-facing endpoints, leaving businesses to pay for traffic that produces no genuine customers. The attack can target OTP requests, sign-up and lead forms, transactional notifications, marketing campaigns, and chatbot endpoints; it may appear as a sudden spike or as distributed low-volume traffic that accumulates over days or weeks. Suggested detection measures include monitoring traffic by use case and geography, reconciling spend with conversions, examining clustered phone-number patterns, and analyzing incomplete forms. The prevention guidance covers CAPTCHA, behavioral bot detection, rate limits, geographic controls, delayed OTP requests, alternative verification methods, and Twilio products including Verify Fraud Guard, SMS Pumping Protection, and Lookup SMS Pumping Risk Score.
How to Build a Voice AI Agent with OpenAI's GPT-Live, Twilio Agent Connect, and Python
This tutorial shows how to build a phone-based voice AI agent with OpenAI's GPT-Live, Twilio Agent Connect, and Python. It configures TAC's GPTLiveProvider to bridge Twilio Programmable Voice Media Streams to GPT-Live-1 in the OpenAI API, using 8kHz mu-law audio and avoiding custom WebSocket plumbing. The tutorial sets a proactive greeting, exposes a Python weather function through Responses delegation, and runs the function outside the real-time voice loop so a simulated three-second backend delay does not block the conversation. The resulting setup handles inbound calls through a Twilio webhook and outbound calls with an E.164 number, while the tutorial also notes per-call customization and alternative voice providers.
Build Voice AI Experiences with Twilio and GPT-Live-1 in the OpenAI API
The post introduces a Twilio Agent Connect integration for building production-ready voice AI experiences with OpenAI’s GPT-Live-1 speech-to-speech model. It addresses the gap between real-time speech intelligence and customer-facing communications by connecting GPT-Live-1 to Twilio Voice and Conversations while preserving context across channels and supporting reliable scale. The SDK supplies a native GPTLiveProvider that links Twilio Voice Media Streams directly to the OpenAI API without custom WebSocket plumbing, and handles turn-taking, audio streaming, interruption handling, and tool delegation. Tutorials, documentation, and example repositories cover inbound and outbound agents implemented with Python and Node.js, giving developers materials to build, test, and deploy voice applications.
121+ Cyber Monday email subject line examples in 2026
Cyber Monday email marketing depends on subject lines to help messages stand out in a crowded inbox, even when designs and discounts are strong. The guide recommends pairing subject lines with preview text, emphasizing exclusivity and urgency, stating discount amounts, using emojis selectively, and keeping copy concise. It also covers personalization, segmentation, pre-event notices, abandoned-cart messages, and reminders. More than 121 examples and templates are organized into Cyber Monday, pre-event, FOMO, abandoned-cart, and emoji-heavy categories, with additional seasonal resources. The post positions Twilio SendGrid for campaign execution and reports 75.1 billion emails processed during Cyber Week in 2025, a 14.6% increase over the previous record-breaking sending, but provides no comparative performance results for the example lines.
Build an AI Voice Assistant with Twilio Voice and Media Streams, OpenAI's GPT-Live API, and Node.js
This tutorial shows how to build an AI voice assistant that answers phone calls using Twilio Programmable Voice, Twilio Media Streams, OpenAI's GPT-Live-1, and Node.js. GPT-Live-1 acts as the speech-to-speech model for listening, talking, and handling interruptions, while the delegated gpt-5.6-terra model handles deeper reasoning and tool use. The implementation uses a Fastify server with WebSocket support, dotenv configuration, a marin voice, and separate prompts for the voice and backend roles. Callers can request a city's top headline through the custom get_top_headline function or ask factual questions through OpenAI's hosted web_search tool. The guide exposes port 5050 with ngrok, points a Twilio number at an /incoming-call webhook, and concludes that the working example fits in under 200 lines.
Make Outbound Calls with Twilio Voice and Media Streams, GPT-Live-1 in the OpenAI API, and Node.js
This tutorial shows how to build an outbound AI voice agent that uses Twilio Programmable Voice and Media Streams to call a permitted phone number, rather than waiting for inbound calls. It connects the call to GPT-Live-1 in the OpenAI API through a Node.js server, with Fastify, ws, dotenv, and the Twilio helper library handling the application and relay. The implementation reads the destination from a --call flag, validates E.164 formatting, exposes the server through a public tunnel, and uses environment variables for credentials and the calling number. Owlie identifies itself as an AI assistant, retrieves a callback note with get_callback_reason, delegates factual questions to hosted web_search, and can be interrupted during speech. The completed demo rings the chosen number, explains why it is calling, and can return random callback notes or web-searched answers, while the tutorial stresses verified numbers, model access, and outbound-calling compliance.
10+ best practices to improve your email deliverability
Email deliverability determines whether messages reach inboxes rather than merely being accepted by recipient mail servers, and the guide distinguishes delivery rate from inbox placement. It recommends authenticating domains with SPF and DKIM, using appropriate IP allocation and warm-up, applying double opt-in, writing genuine subject lines, offering preference controls, cleaning lists, avoiding purchased addresses and spam traps, sending valuable content, and monitoring metrics. The stated benchmark for good deliverability is at least 95%, while the excerpt cites Twilio SendGrid's 99% API rate and warns that changing providers does not repair domain or IP reputation. Case studies report Shopify at 99.5% overall delivered and 91.3% inbox placement, and Klaviyo at 99.94% average delivery, with the latter also reporting 1.9-second median delivery speed.
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