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April 14Tuesday
  1. Vapi Blog27

    Vapi Engineers Share Lessons on Deploying Voice AI at Enterprise Scale

    Vapi's Forward-Deployed Engineers say the demo-to-production gap is where most enterprise voice AI initiatives stall, requiring extensive testing, guardrails and intent-based design rather than exact phrase matching. The team warns of "personality drift," where agents adopt callers' speech styles, and notes LLMs are non-deterministic, so deployments need defined error tolerance and continuous iteration. They advise starting with cost optimization but targeting revenue generation, and benchmark a good interaction at under a minute.

April 1Wednesday
  1. Vapi Blog18

    Vapi Launches Enhanced Security Mode for Enterprise Voice AI Audio Privacy

    Vapi released Enhanced Security Mode, an audio privacy layer it calls the quietest and most secure ever deployed in an enterprise voice AI platform, designed to prevent AI agent speech from being overheard in open spaces. The company says its entire audio pipeline was re-engineered to invert signal-presence optimizations without adding latency artifacts. Early access covered healthcare, benefits administration, and post-acute care organizations, and the feature is available now.

March 20Friday
  1. Vapi Blog38

    Vapi Webinar Answers Top Questions on Composer Voice Agent Builder

    Vapi hosted a webinar in which Principal Product Manager Nick Robin demoed Composer, its in-product assistant for building voice agents without code, producing a working inbound customer service agent within a 30-minute demo. Composer writes system prompts, provisions phone numbers, sets scheduling and flags its own errors for approval. It is currently in alpha and supports both inbound and outbound assistants, CRM and calendar integrations, and editing of existing agents by assistant ID.

February 11Wednesday
  1. Vapi Blog55

    Vapi launches Composer, an in-dashboard AI assistant that builds voice agents

    Vapi shipped Composer, an AI assistant inside the Vapi Dashboard that builds voice agents from a description, writing the prompt, configuring settings, provisioning phone numbers, building tools and setting up integrations. Composer can also pull call logs to explain a failed call and apply a fix, and generate custom code tools that run on Vapi's infrastructure for integrations such as HubSpot. It is available now in Alpha with no setup or onboarding flow.

December 17, 2025Wednesday
  1. Vapi Blog38

    Vapi Voices Beta Launches at $0.0025/min for High-Volume Voice AI

    Vapi released Vapi Voices Beta, a family of voice models built for high-volume, cost-sensitive voice AI use cases, priced at $0.0025 per minute with latency optimized for conversational responsiveness. The models appear in the existing voice dropdown alongside providers like ElevenLabs, PlayHT and Deepgram, so teams can route high-volume, low-stakes flows such as appointment reminders and routing menus to them with zero integration changes. Vapi says it is gating general availability on what beta usage reveals about use cases, latency under real load and whether the savings matter.

November 20, 2025Thursday
  1. Vapi Blog42

    Vapi adds structured outputs to extract schema-validated data from voice AI calls

    Vapi now supports structured outputs for all voice AI assistants, ensuring every call returns data that matches a developer-defined JSON schema. Schemas are enforced at runtime using provider-native capabilities from OpenAI, Anthropic, Gemini and others, and can be reused across multiple assistants. Extracted data arrives in call completion webhooks and the REST API.

November 19, 2025Wednesday
  1. Vapi Blog35

    GPT-5.1 Brings Personality Presets to Voice AI, Now Live on Vapi

    OpenAI's GPT-5.1 adds consistent personality presets — Default, Professional, Friendly, Candid, Quirky, Efficient, Nerdy, and Cynical — plus a more conversational GPT-5.1 Instant and fast adaptive reasoning that gives simple questions quick replies while complex ones get more thinking. Vapi says the model went live on its platform last week alongside OpenAI's announcement, letting voice agents adopt brand-consistent tones without prompt rewrites.

November 13, 2025Thursday
  1. Modal Blog40

    How Decagon Shipped Real-Time Voice AI on Modal

    Decagon and Modal partnered to build Decagon Voice 2.0, cutting latency by 65% while improving intent recognition and response quality. Decagon fine-tuned compact open-source models with SFT and RL to surpass larger frontier models, while Modal trained a custom EAGLE3 draft model with 38% higher accept lengths and re-engineered SGLang with an async speculative decoding scheduler, boosting throughput up to 12%.

November 12, 2025Wednesday
  1. Vapi Blog18

    Vapi Founder Recounts Building VapiCon, the First Voice AI Summit

    Vapi founder recounts how the company staged VapiCon, billed as the first Voice AI summit, drawing 850 attendees and voice AI leaders from OpenAI, Deepgram and Assembly AI into one room. Vapi spent about $500,000 on the event and made roughly $400,000 back, with the founder citing partnerships and enterprise deals as the real return. The company has now launched a VapiCon Video Library of every session and panel.

November 4, 2025Tuesday
  1. Modal Blog58

    Modal, Pipecat and open models achieve one-second voice-to-voice latency

    Modal's Ben Shababo walks through building a conversational voice bot on Modal with the open source Pipecat framework and open weights models, reaching a median voice-to-voice latency of about one second when the client and containers are geographically close. The pipeline uses NVIDIA parakeet-tdt-0.6b-v3 for STT, Qwen3-4B-Instruct-2507 served with vLLM, KokoroTTS for speech output, and ChromaDB with all-minilm-l6-v2 for RAG over Modal's docs. Modal Tunnels bypass the input plane for low-latency WebSocket and HTTP links to the STT, TTS and vLLM services, while a FunctionCall tied to each conversation session recovers autoscaling, and pinning services to nearby regions cuts network latency.

October 27, 2025Monday
  1. Vapi Blog28

    Vapi Offers a Free Week of Cartesia Sonic-3 TTS

    Vapi is giving its community free, unrestricted access to Cartesia's newly launched Sonic-3 TTS model through its managed API key from October 28 through November 2. Sonic-3 adds emotion and laughter tags, fine-grained speed and volume controls, and support for 27 new languages. Vapi recommends starting with the Kira and Ariana voices for low-latency, natural-sounding agents.

August 28, 2025Thursday
  1. Modal Blog22

    How Zencastr transcribed hundreds of years of audio in days with Modal

    Zencastr moved its podcast transcription workloads to Modal's GPU platform, scaling to 1,500 concurrent GPUs within minutes to process hundreds of years of audio in just a few days. The shift from self-managed Kubernetes GPU nodes to Modal's scale-to-zero infrastructure cut idle GPU costs and removed driver and dependency management overhead. All core ML workloads now run on Modal, including transcription, speaker counting, laughter detection, and audio quality scoring.

July 23, 2025Wednesday
  1. Modal Blog52

    Modal benchmarks open ASR models for batch transcription at 100x speed and cost gains

    Modal implemented a batch transcription service on its platform using NVIDIA's parakeet-tdt-0.6b-v2 and canary-1b-flash, reporting over 100x faster or 100x cheaper end-to-end performance than a popular proprietary ASR API while matching its error rate on roughly a week of ESB benchmark audio. The team attributes the gains to shuffling files across request batches, sorting audio by duration within GPU batches, parallel downloads, and empirically chosen GPU and worker configurations. The post walks through the architecture and optimization steps so others can build similar services.

June 26, 2025Thursday
June 24, 2025Tuesday
  1. Vapi Blog22

    Mistral vs Llama 3: A Complete Comparison for Voice AI Applications

    Mistral and Llama 3 split on philosophy for voice AI: Mistral's 7B to Mistral Small 3.1 (24B) models favor low-latency efficiency, while Llama 3 scales from 8B to 70B for stronger reasoning and multilingual reach. Mistral Small 3.1 reaches 0.29s time to first token at 150-166 tokens per second, and Mistral Small 24B beats Llama 3.1 8B Instruct on ARC-C, GPQA and MMLU, while Llama 3.1 405B scores 85.2% on MMLU and 96.8% on GSM8K.

June 23, 2025Monday
  1. Vapi Blog22

    8 Alternatives to Azure for Voice AI STT on Vapi

    Vapi now offers eight speech-to-text providers — Gladia, AssemblyAI, Deepgram, Cartesia, Talkscriber, OpenAI, Speechmatics and ElevenLabs — as drop-in alternatives to Azure for voice agents. Switching providers takes a single JSON parameter change, letting developers benchmark latency, cost and compliance. Gladia claims sub-100 ms end-to-end latency, AssemblyAI bundles summaries and PII redaction in one API call, and Cartesia runs fully on-premises.

June 18, 2025Wednesday
  1. Vapi Blog18

    Five Ways Real Estate Agents Can Use AI

    A guide outlines five ways real estate agents can use AI, including voice agents built on Vapi that answer calls, qualify leads, and book showings around the clock. It also covers automating content with ChatGPT and Canva, plus AI pricing tools such as HouseCanary and CoreLogic that produce valuations with confidence scores.

June 17, 2025Tuesday
  1. Vapi Blog38

    Deepgram Nova-3 vs Nova-2: How the STT Engine Evolved

    Deepgram's Nova-3 cuts streaming word error rate from Nova-2's 8.4% to 6.84% and reaches 5.26% batch WER, a 54.3% reduction in streaming errors. Nova-3 replaces Nova-2's separate domain-specific models with a single adaptable network and adds real-time multilingual conversation handling, up to 100 self-serve custom terms without retraining, and redaction for up to 50 entities. Both models run natively on Vapi with identical endpoints, so switching is a parameter change, though Nova-3 sits at Deepgram's premium pricing tier.

June 5, 2025Thursday
  1. Vapi Blog22

    GPT-4.1 vs Claude 3.7 Sonnet: Which AI Delivers Better Voice Agents?

    Vapi compares GPT-4.1 and Claude 3.7 Sonnet as the LLM behind voice agents, weighing conversation quality, context handling, reasoning transparency, platform integration and cost. GPT-4.1 offers a 1,000,000-token context window and 32,768-token outputs with 75% caching discounts, while Claude 3.7 provides a 200,000-token context and 128,000-token outputs. Both models are selectable on Vapi's voice agent platform.

June 4, 2025Wednesday
  2. Vapi Blog22

    Three Examples of Voice AI Improving Logistics

    Vapi outlines three voice AI use cases in logistics: ShipEX uses voice intelligence across 350 trucks to route maintenance alerts and accident reports, the Idaho State Liquor Division's voice picking system lifted pick rates 35%, and maintenance technicians log issues by voice to auto-create CMMS work orders. The article also details API integration with TMS, CRM, and WMS systems and deployment considerations.

  3. Vapi Blog22

    11 Great ElevenLabs Alternatives: Vapi-Native TTS Models

    Vapi now offers 11 built-in text-to-speech models as alternatives to ElevenLabs, including Neuphonic's Neu-hq and Neu-fast, Cartesia's Sonic lineup, Azure TTS, OpenAI TTS, Deepgram, Smallest AI's Lightning, LMNT, PlayHT, Hume's Octave and Rime AI's Mist v2. Developers can switch between them in minutes without re-coding, and Vapi says it handles over a million voice calls per day across these models.

May 30, 2025Friday
  1. Vapi Blog15

    Best Speechify Alternatives: 5 TTS Tools Compared

    A comparison of five Speechify alternatives picks NaturalReader for cross-device use and app integrations at $119 per year, Voice Dream Reader for iPhone voice control at a $14.99 one-time price, and Murf AI for professional voices from about $19 per month. ReadSpeaker focuses on reading web pages across 45 languages from $4.90 per month, while Balabolka is a free Windows-only option.

May 29, 2025Thursday
  1. Vapi Blog25

    Choosing Between Gemini Models for Voice AI

    Vapi outlines how to pick among four Gemini models for voice agents: Gemini 1.0 Pro for predictable, compliance-friendly flows at $0.50 input and $2.00 output per million tokens, Gemini 1.5 Flash for high-volume work with a 1M token context window, Gemini 1.5 Pro for deep reasoning with a 2M token window and 99.7% long-context retrieval accuracy, and Gemini 2.0 Flash for native tool calling.

May 26, 2025Monday
  1. Vapi Blog10

    Introduction to SRTP: Secure Real-Time Transport Protocol

    SRTP secures RTP voice and video streams by adding encrypted payloads, authentication tags, and a master key identifier to each media packet. It relies primarily on AES counter mode and HMAC-SHA1 authentication tags, with sequence numbers blocking replay attacks, and pairs with DTLS-SRTP or SDES for key exchange. SRTP is positioned as a lower-overhead, application-layer option for real-time communications, with GDPR, HIPAA, and CPRA cited as compliance drivers.

  2. Vapi Blog18

    Env Files and Environment Variables for Voice AI Projects

    A guide on using .env files and environment configuration in voice AI projects, covering dotenv setup for Node.js and Python, adding .env to .gitignore, and Vapi-specific keys like VAPI_API_KEY and VAPI_PROJECT_ID. It cites GitGuardian's finding of 12.8 million secrets leaked on GitHub in 2023, a 28% increase, and recommends separate env files per environment plus tools such as git-crypt, SOPS, AWS Secrets Manager and HashiCorp Vault.

May 23, 2025Friday
  1. Vapi Blog18

    Top 5 Character AI Alternatives for Seamless Voice Integration

    A Vapi blog roundup lists five Character AI alternatives for voice integration: Vapi, AnimaAI, JasperAI, Novel AI and AI Dungeon. Vapi is pitched as an API-native Voice AI platform supporting 100+ languages, connecting to 40+ applications, with Sesame-powered voice agents and automated test suites for catching hallucinations.

  2. Vapi Blog18

    Amazon Lex vs Dialogflow: Complete Platform Comparison Guide

    Amazon Lex suits teams already on AWS needing tight integration with Amazon services, while Dialogflow offers broader language support and an easier learning curve for newcomers. Lex uses Alexa's technology with pay-as-you-go pricing including a free tier of 10,000 text and 5,000 speech requests monthly for the first year, and Dialogflow supports over 30 languages with pre-built agents and sentiment analysis.

  3. Vapi Blog18

    Narakeet: Turn Text Into Natural-Sounding Speech

    Narakeet converts written scripts into lifelike voiceovers, offering 600+ voices across 70+ languages and support for 140+ languages and dialects. The platform syncs narration with PowerPoint, Google Slides, and Markdown files, generates subtitles and captions, and provides a developer API with batch processing. Plans start around $5 per month, with a free tier available.

May 22, 2025Thursday
  1. Vapi Blog20

    The 10 Best Open-Source Medical Speech-to-Text Tools

    A guide ranks 10 open-source speech-to-text models for clinical use, evaluated on real-time accuracy, clinical terminology handling, operational reliability and data security. The list covers Vosk, DeepSpeech, SpeechBrain, OpenAI Whisper and ESPnet, matched to settings such as low-resource rural clinics, multilingual hospitals and terminology-heavy research centers. All can be integrated with Vapi's model-agnostic voice AI platform.

April 22, 2025Tuesday
April 18, 2025Friday
  1. Vapi Blog40

    Vapi Launches MCP Server to Control Voice Agents from Claude Desktop and Cursor

    Vapi released the Vapi MCP Server, letting AI agent tools trigger real-time voice flows and outbound calls via function calling. It supports Claude Desktop integration and remote access over SSE, so users can ask Claude to place calls or schedule follow-ups in plain language. The server is available via @vapi-ai/mcp-server, locally or through a hosted SSE endpoint.

April 1, 2025Tuesday
  1. Vapi Blog20

    Scaling Client Intake with Vapi Voice AI Agents: A Consultant's Case Study

    Consultant Christian Ulstrup of GSD at Work used Vapi voice AI agents to replace scheduled discovery calls with an asynchronous voice intake system for his AI Action Sessions workshops. Participants call a dedicated Vapi phone line at their convenience, and transcripts plus AI-generated summaries flow into Slack via Zapier and are logged in HubSpot. For one recent client, 20 participants across the globe contributed over 3 hours of discovery, and the session earned a 5 out of 5 rating.

March 6, 2025Thursday
  1. Vapi Blog20

    How AI Call Centers Are Changing Customer Support

    AI call centers are reshaping customer support by resolving routine calls in seconds instead of long waits, as in the example of an outage query handled in 30 seconds. Gartner estimates about 25% of customer service interactions will involve AI by 2027, up from 2% in 2022, a market worth $15-20 billion by 2027-2028 at roughly 25-30% CAGR. The article covers traditional call center pain points such as slow response times, peak-hour surges and limited hours, and how AI automation addresses them.