CallMissed Blog
Insights on AI communication, voice agents, WhatsApp automation, and the future of customer engagement.
5 min read
ComparisonMay 8, 2026
GPT-5.5 Thinking vs Instant: When to Use Each
OpenAI's GPT-5.5 line ships in two main flavors plus a Pro tier: Instant, Thinking, and Pro. They are not three different models in the old sense — they are three different reasoning modes over the GPT-5.5 family. Picking the right one is the difference between snappy answers, deep analysis, and bur…
5 min read
ArticleMay 8, 2026
Inside GPT-5.5 Pro: OpenAI's Power-User Tier
GPT-5.5 Pro is the variant most users never touch — it costs roughly six times as much as standard GPT-5.5, requires a Pro/Business/Enterprise plan, and is reserved for the hardest single-shot tasks. But for the workloads that need it, nothing else in the OpenAI lineup is comparable. Here's where Pr…