RedditGPT-5.4 Leaked Extreme Reasoning 1M Context WindowThe Information·high signalXBlueskyLinkedInCopy linkThe Information reports GPT-5.4 with 1M context and extreme reasoning mode. Spotted on LMArena and in Codex commits.SourceSource pageThe Information↳ Follow the threadStack layer / Threat patternClaude Code 2.1.269 Ships a Plugin Eval Runner and a Knob to Raise the Workflow Tool's Concurrent Agent Cap to 256Anthropic (claude-code CHANGELOG)Stack layer / Threat patternGreyNoise Traced One Attacker Running OpenAI's Codex Harness With a DeepSeek Model Through 395 Organizations in 48 CountriesHelp Net SecurityPolicy dependency / Stack layerGitHub adds four VS Code Agents fields to the Copilot usage metrics API, kept separate from editor Agent ModeGitHub ChangelogPolicy dependency / Stack layerClaude Code's agent view adds a peek panel so you can answer a blocked session without leaving the listClaude Code DocsStack layer / ContrastA2ABreak extracts a 37-state machine from the A2A spec and finds 11 protocol-level flaws that a fully compliant attacker can exploitarXivPolicy dependency / Stack layerAnthropic's September threat report: Chinese students produced "more than a dozen possible zero day findings in a single month" with ClaudeAnthropicStack layer / Update threadCodex promotes voice conversations and git worktrees out of experimental and turns both on by defaultGitHubStack layer / ContrastYuE2-3B open music model edges past Suno v5 on WildSongBench and runs in 7.7 GB of VRAM at Q4Hugging Face / m-a-p (via r/LocalLLaMA, 254 upvotes)