Claude Code's isolation: 'worktree' subagents were fixed for reaching into the parent checkout four times, across releases from 2.1.203 to 2.1.222, with the documented scope shifting each time. I lay out what git -C, GIT_DIR, and destructive git commands each broke, from the official release notes.
MCP 2026-07-28 drops initialize, session IDs, and SSE resume; Sampling, Roots, and Logging are deprecated. I wrote minimal servers for both specs and diffed them with curl.
Verified in SymPy: the 3-variable map from Alpöge's post has constant Jacobian determinant −2 yet sends three points to (−1/4, 0, 0). What changes for n ≥ 3 and what stays open.
Fitted Anthropic's jacobian-lens on Qwen3-4B-Instruct-2507 (4090, 51 min, ~1 USD), then read a layer-swapped SFT corrector: outputs pass through while hidden states diverge to cos 0.88.
Swap 'spider' for 'ant' in Claude's mid-layers and 8 legs becomes 6. Anthropic's global workspace paper, the J-lens readout, eval-awareness detection, and its limits.
Anthropic disabled Fable 5 and Mythos 5 for all customers on June 12, 2026. US export controls, foreign-national employees, AI Safety gaps, Microsoft limits, and the shaky Opus 4.8 fallback.
Claude Code sometimes emits a stray court token and raw <invoke> as plain text instead of running Read/Edit/Bash — a malformed tool call that never executes. How to tell it from a hung shell or a 'could not be parsed' error, on long Opus 4.8 sessions.
Reading Anthropic's postmortem and the DEV operational report in the same week reveals that Claude Code's quality degradation and Max weekly quota exhaustion are not separate incidents—they're two sides of the same quality×cost design decisions. A timeline and operational priority walkthrough.
Anthropic Labs released Claude Design on April 17, 2026 — a new design product that reads your codebase and existing design files to generate prototypes, slides, and landing pages. Here is a feature comparison with Figma and Canva, and a scenario-by-scenario guide to which tool to open when.
Measured: Opus 4.7 burns 1.2-1.45x tokens vs 4.6 in community benchmarks (Bill Chambers' Tokenomics Leaderboard, Claude Code Camp), beating Anthropic's official 1.0-1.35x range. CLAUDE.md alone hits 1.4-1.45x.
Anthropic released Claude Opus 4.7 on April 16, 2026. The staged rollout adds an xhigh effort tier, self-verification before returning, and roughly 3x higher-resolution image input, while intentionally capping cyber capability under Project Glasswing.
A breakdown of Claude Code Routines, released as a research preview on April 14, 2026. Covers the three trigger types (schedule, API, GitHub), routine structure, and autonomous execution on Anthropic-managed infrastructure.
