Thread by @ClaudeDevs on Thread Reader App

This "article" is really a Thread Reader unroll of several separate Twitter/X posts from Anthropic, spanning roughly late July through early October, and it bundles together a few different announcements. The biggest is the MCP 2026-07-28 release, which makes the Model Context Protocol stateless. Before, running a remote MCP server meant managing session state, which tied you to certain infrastructure. Now it can run on serverless and edge platforms or scale horizontally behind a standard load balancer. The update also adds a formal extensions mechanism, with examples including MCP Apps (server-rendered UIs in a sandboxed iframe), Tasks for long-running async work, and Enterprise Managed Auth for controlling server access through an identity provider. On the Claude Code side, there are three threads. Users can now customize the tool with plugins: mods can change behavior, alter the UI, or add features, and they install through the /plugin command. The two sample mods are Token Weather, which shows context window fullness and a sparkline of recent turns, and Blast Radius, which intercepts risky shell commands like rm -rf or force pushes and previews what they would touch. Remote Control also got reliability work: you can start a session from your phone via a device card on any machine running claude remote-control, and the phone stays synced with sessions resumed on a laptop and marks sessions offline within seconds when Claude Code exits. The thread also announces Opus 5.5, which Anthropic says performs at the level of "Fable 5.1" and runs about 30% faster and 40% cheaper per task than Opus 5. It is now the default for paid plans, with session limits raised 20% and a one-time usage reset available in Settings until October 22. The remaining posts cover Claude Managed Agents and an open-source release. Managed Agents gained per-session budgets that pause a session with a budget_reached event until the limit is raised, a model.inference_geo setting that either runs at standard rates wherever capacity exists (global) or keeps inference in-region at 1.1x cost (us), and automatic loading of skills from .claude/skills/ in attached repositories. Separately, Anthropic open-sourced Claude Commerce Agents, a blueprint with reference implementations for retail, travel, telecom, and entertainment, which the company says has helped retailers see carts up to 35% larger and shoppers 60% more likely to complete a purchase.