A roundup of recent Anthropic posts on Twitter/X covering customizable Claude Code mods, the Opus 5.5 model with usage limit boosts, and the 2026-07-28 MCP spec release that makes the protocol stateless. The thread itself is a collection of tweets, so this is a digest rather than a single argument.

• Claude Code can now be modded through plugins, with examples like Token Weather (context window forecast) and Blast Radius (flags risky shell commands before they run).
• Opus 5.5 is reported as roughly 30% faster and 40% cheaper per task than Opus 5, becoming the default for paid plans, with 5-hour session limits raised 20% and a one-time usage reset available until Oct 22.
• MCP 2026-07-28 makes the protocol stateless, so remote servers can run on serverless or edge infrastructure and scale horizontally, and adds formal extensions like MCP Apps, Tasks, and Enterprise Managed Auth.

Anthropic has released 11 open-source plugins that turn Claude into a specialist for roles like sales, legal, finance, and product management. Each plugin bundles skills, slash commands, and connectors to tools like Slack, HubSpot, and Jira, and can be customized to match a company's own workflows.

• Each plugin is file-based (markdown and JSON) with a fixed structure: a manifest, MCP connector config, slash commands for explicit actions, and skills that Claude draws on automatically.
• Eleven plugins cover productivity, sales, customer support, product management, marketing, legal, finance, data, enterprise search, bio-research, and plugin management.
• The plugins are generic starting points meant to be customized by swapping connectors, adding company context, and adjusting workflows, with installation via a Claude Code marketplace command.

The 15-page PDF lays out a four-step loop—write, consolidate, recall, apply—to give AI agents a persistent memory. Agents log each attempt, distill lessons into reusable insights, review those insights before new tasks, and skip past dead ends. Anthropic engineers use this approach in Claude Code to boost agent performance.

• A 15-page PDF from a senior Anthropic engineer outlines a four-step memory loop for AI agents: Write, Consolidate, Recall, Apply
• The system distills messy task logs into a handful of reusable lessons rather than replaying full transcripts
• Agents use these distilled lessons to skip previously failed approaches even on new tasks
• Anthropic has already integrated this loop into Claude Code, with setup scripts available to inspect

Two Anthropic engineers spend 24 minutes unveiling undocumented Claude Code features that most users overlook. They demonstrate hidden functions and shortcuts in this video, suggesting it could overhaul your AI workflow.

• The described "hidden features" (debug verbose mode, memory slots, S3 auto-fetch, experimental rate limiter) are not real documented Claude Code capabilities and the syntax shown (//verbose, ///MEMORY SLOT, <s3://...>) appears fabricated
• The claims of auditing internal reasoning, persistent cross-session memory slots, automatic S3 file parsing, and a 30% cost-cutting rate limiter should be treated as unverified or likely false rather than genuine product functionality

Two Anthropic engineers walk through every lesser-known Claude Code capability in a 24-minute session. They uncover shortcuts, tools, and tricks most users never try, so you can get more out of the platform.

• The provided summary details features (in-browser REPL, YAML tool plugins, "Explain error" button, 10-user shared workspaces) that don't match any known Claude Code product, suggesting fabricated or hallucinated content.
• The source is just a Twitter/X handle (@sairahul1) with no actual article body given, making the "detailed summary" unverifiable against real content.

Anthropic investigated user reports of degraded performance in Claude Code, the Agent SDK, and Cowork, and traced them to three separate changes: a lowered default reasoning effort, a bug that cleared session context on every turn after idle, and a prompt tweak to limit verbosity. All issues were reverted or fixed by April 20 (v2.1.116), and Anthropic is adding stricter testing, broader internal dogfooding, and more targeted evals to prevent similar regressions.

• Three unrelated changes (lowered reasoning effort, a context-clearing bug, and a verbosity-limiting prompt tweak) independently degraded Claude Code quality, and all were rolled back or fixed by April 20 (v2.1.116).
• A March 26 bug meant to prune old reasoning after an hour of idle time instead cleared context on every turn, causing Claude to forget logic, repeat itself, and make bad tool calls—while also burning through users' rate limits faster via cache misses.
• The default reasoning effort was dropped from high to medium on March 4 to reduce latency, but users found it dumbed-down, so it was reverted on April 7 to x-high (Opus 4.7) or high (other models).
• Because the three issues hit different traffic subsets at different times, users experienced inconsistent symptoms—slowdowns, forgetfulness, quality drops—making the problem hard to diagnose until late April.

Anthropic has introduced repeatable routines in Claude Code that run on its web infrastructure, so tasks execute even if your Mac is offline. The feature, now in research preview, lets Pro, Max, Team, and Enterprise users schedule automations with repo and connector access, subject to daily run limits. The update also includes a redesigned Mac app with parallel sessions, an integrated terminal, file editing, and preview tools.

• Claude Code now runs scheduled "routines" on Anthropic's servers, so automations execute even when your Mac is offline
• Daily routine limits scale by plan: 5 for Pro, 15 for Max, 25 for Team/Enterprise
• Routines come pre-connected to repos and connectors, eliminating manual cron job or server setup
• The redesigned Mac app adds parallel sessions with a sidebar, plus a built-in terminal, file editor, and HTML/PDF preview pane

The article breaks down the recently leaked source code of Anthropic's Claude Code CLI. It highlights the system's architecture, design choices, and differences from OpenAI's Codex, particularly in handling context overflow and user interactions. Key features like compaction strategies and internal versus external user instructions are explored.

• Claude Code uses a four-tiered compaction strategy (proactive token monitoring, reactive fallback, and a "snip compaction" mode for headless sessions) versus Codex's simpler diff-based approach that just minimizes data sent per turn
• The system prompt uses a boundary marker to cache roughly 3,000 tokens of static instructions across users for performance gains
• Internal users get specialized instructions specifically designed to stop the model from misrepresenting test results or giving misleading status updates
• The codebase includes feature flags and build-time checks specifically to prevent sensitive information from leaking into public builds

Anthropic unintentionally exposed the source code for Claude Code, its AI product, through a public npm package. The leak, which includes sensitive architectural details, poses significant risks for users and gives competitors insights into its technology. Users are advised to take immediate security precautions due to potential vulnerabilities.

• A source map on public npm exposed ~512,000 lines of Claude Code's TypeScript source, discovered by an intern rather than Anthropic itself.
• The leak reveals unreleased internal architecture like "Self-Healing Memory," "Strict Write Discipline," and the always-on "KAIROS" background agent.
• Internal metrics show development problems including a high false claims rate, plus an "Undercover Mode" letting Claude Code contribute to open-source projects without disclosing its identity.
• Users who updated packages around the leak window face added risk from a separate, unrelated malicious attack on the axios package.

Feedback is valued and taken seriously, with an emphasis on user input for improvements. For detailed information on available qualifiers, users are directed to the documentation. An error occurred while loading the page, prompting a reload.

• The page failed to load an error, so the actual content of the ralph-wiggum plugin page wasn't accessible
• The available text is just GitHub boilerplate (feedback prompt, search qualifier docs link, reload notice) rather than substantive article content

Boris and Cat, the team behind Claude Code, explain how a terminal tool grew out of an internal prototype after an engineer was told to use it instead of hand-writing code. They cover why giving the model bash and a few tools worked better than building a custom toolkit.

• Claude Code began as an internal research tool called Clyde. A new engineer's hand-written PR got rejected with "use Clyde," and the one-shot result convinced the team that an IDE might not be necessary.
• The turning point was giving the model bash. It started writing AppleScript and automating things on its own, which the team had not expected.
• Anthropic "dogfoods" the product: roughly 70 to 80 percent of technical staff use it daily, and internal feedback arrives constantly, so features get shipped or pulled within days.
• The team has been removing tools over time. The LS tool was dropped once bash permissions could enforce directory restrictions, which leaves less clutter in the model's context.