#anthropic articles

Claude 6か月無料の申込フォーム｜OSS向けMax 20x取得手順

Claude を6か月無料で使える唯一の公式ルート『Claude for Open Source』を解説。対象は GitHub 5,000スターや NPM 月100万DLの OSS メンテナで、Claude Max 20x(計$1,200相当)を取得できる。申込フォームの記入項目、審査のコツ、6か月後の扱いまで整理。

Claude Opus 4.5 の料金は？入力$5・出力$25・Batch割引を解説

Claude Opus 4.5 の API 料金は入力 $5・出力 $25/百万トークン。前世代 Opus 4.1 から 67% 値下げで常用圏へ。Batch API 50% 割引・プロンプトキャッシュ・Extended Thinking の追加コストまで整理。

Claude Opus 4.6 料金 — $5/$25・Fast mode・Batch 割引まとめ

Claude Opus 4.6 の API 料金は入力 $5・出力 $25/百万トークン。Opus 4.1 比 67% 値下げで常用圏へ。Fast mode（$30/$150）・Batch API（50% 割引）・1M コンテキスト標準料金・プロンプトキャッシュまで整理。

How to Use Claude Code | 5 Extensions + 3 Operations from Anthropic's Employee Playbook

A detailed explanation of Anthropic's internal Claude Code playbook. Learn about the 5 extension features — CLAUDE.md, Hooks, Skills, Plugins, and Managed Agents — and 3 operational patterns: team sharing via CLAUDE.md, safety guardrails with hooks, and supervisory models. A step-by-step guide for rolling these out in your team.

What Is Claude Opus 4.5 | 76% Token Reduction Compared to Sonnet 4.5 Explained

A breakdown of Claude Opus 4.5's capabilities and pricing. At $5 input / $25 output — Sonnet-level pricing — it delivers roughly 67% cost reduction over Opus 4.1, and at medium Effort achieves Sonnet 4.5-equivalent accuracy with 76% fewer tokens. Covers how to use the Effort parameter and how to leverage prompt caching and batch inference.

Claude Opus 4.1 / 4.5 / 4.6 / 4.7 | Performance & Pricing Comparison

A four-axis comparison of Claude Opus 4.1 / 4.5 / 4.7 across SWE-bench score, pricing, speed, and migration risk. For autonomous agents, Opus 4.7 with SWE-bench 87.6% is the top choice; for cost savings, Opus 4.5 at $5 input is optimal; to avoid breaking changes, sticking with Opus 4.6 is the practical solution.

What is Claude Opus 4.1 | SWE-bench, Pricing, and Changes Explained

A breakdown of Claude Opus 4.1's changes, pricing, and API identifier usage. At the same price as Opus 4 ($15 input / $75 output per 1M tokens), it enhances multi-file refactoring and long-document search quality, achieving 74.5% on SWE-bench Verified. Includes guidance on when to pin a snapshot for stable production behavior.

What Is Claude Keep Thinking | Extended Thinking Feature Explained

Claude 2026 Report | ARR $30B Achieved and Market Share Explained

A breakdown of Anthropic's ARR $30B milestone and market share. Covering the background behind roughly 1,400% year-over-year growth that surpassed OpenAI, the rapid expansion of Claude Code reaching $2.5B ARR on its own, the enterprise-driven structure with 70% of the Fortune 100 as customers, and a look at where Claude still trails ChatGPT and Gemini in traffic.

Claude 2026 Reddit Roundup | The Real Opinions of a 740K-Member Community

Claude 2026 Promotions | Double Usage, Discounts & How to Save

A guide to Claude discounts and smart ways to save. Covers the annual plan discount (Pro drops to ~$17/month), the March 2026 double-usage campaign, how to stay informed about future promotions via the official Help Center and Hacker News, and the reality that third-party promo codes do not exist.

What Is Claude's Constitution? | Anthropic AI Ethics Document Explained

A complete guide to the 2026 version of Claude's Constitution, published by Anthropic under a CC0 license. Covers the expansion to approximately 23,000 words, the shift from rule-enumeration to a reason-based design, the four-tier priority hierarchy of safety, ethics, principles, and helpfulness, and the unprecedented official acknowledgment of AI consciousness and moral status.