Coding agents

• Claude Code v2.1.280 ships Opus 5.5 as the default Opus model (1M context, $4/$20 per Mtok, $0.20/Mtok cache reads) plus mouse support in fullscreen lists.
• Projects rolls out in Claude Code desktop/web: one conversation auto-splits into parallel cloud-run threads that keep working after you leave, in beta.
• Claude Code adds AGENTS.md support: with no CLAUDE.md present, v2.1.277 reads AGENTS.md instead, via the new "Claude Code mods" customization layer.
• v2.1.277 release notes confirm the AGENTS.md fallback and add CLAUDE_GATEWAY_PROXY_IS_EGRESS_BOUNDARY=1 for gateway deployments with a single forward-proxy egress.
• v2.1.274 adds a critical-memory warning, CLAUDE_CODE_MCP_STARTUP_WAIT_MS to bound MCP connect waits, and an effort attribute on the claude_code.llm_request OTel span.
• cline/cline is an open-source coding agent shipped as SDK, IDE extension, and headless CLI, usable in CI/CD via npm i -g cline.
• strands-agents/harness-sdk is an open-source Python/TS SDK for an in-process agent loop with turn limits, token budgets, cancellation, tools, and MCP, no hosted control plane.
• GitHub's Project HydraFusion routes Copilot workflows across multiple models, matching Opus 5 quality at lower cost in offline evals, now a research preview.
• affaan-m/ECC is a performance-optimization layer (skills, instincts, memory, security) for agent harnesses across Claude Code, Codex, Opencode, Cursor; install only from verified channels.
• addyosmani/agent-skills packages senior-engineer workflows (define/plan/build/verify/review/ship) as portable skills for coding agents.

LLM mechanics

• Anthropic ships Claude Opus 5.5, first of the 5.5 family: performs near Fable 5.1 on most tasks at 40% lower cost than Opus 5, externally red-teamed by Frontier Design and METR.
• artificialanalysis.ai's benchmark puts Opus 5.5 in the top-intelligence tier but pricier than peers at similar capability; community reports only marginal code-quality gains and possible post-launch degradation.
• Simon Willison tracks the pile-up: Opus 5.5 lands the same week as Grok 4.7, MiMo v2.6, and GPT-6 Sol/Luna, all cutting prices in the same window.
• Latent.space frames Opus 5.5 as the price-war trigger: OpenAI's GPT-6 Sol/Luna cut 50%, Anthropic answers with Opus 5.5 at 40% less than Opus 5.
• bcherny used Opus 5.5 to formally verify the Claude Agent SDK in Lean, a couple prompts yielding 16 PRs fixing bugs and race conditions; also combines Lean with TLA+ for concurrency/data-flow modeling.

CLI/TUI

• davila7/claude-code-templates is a CLI for configuring and monitoring Claude Code, now bundling Bright Data skills/MCP for web search and scraping.

Vibe-coding & repos

• BuilderIO/agent-native is a TypeScript framework where each app capability is defined once as an "action" that both the agent calls as a tool and the UI calls as code.
• A 10-tool roundup of local, free Claude Code add-ons leads with Serena, which turns Claude Code into an IDE that edits by symbol instead of grepping whole files.
• obra/superpowers is a full dev methodology for coding agents built on composable skills that force a plan-before-code step at session start.
• bcherny argues Claude Code proved agents can ship real features unattended, and that pattern is now merging chat and Cowork into one agent that carries context across both.

Agentic SaaS

• tech-leads-club/agent-skills is a validated skill registry positioned against a stat that 13% of marketplace skills carry critical vulnerabilities.
• A thread points to an open skill directory installable in one command across Claude Code, Cursor, Codex, and Gemini.
• Skillsync (YC W26) launches to make AI chat sessions portable across agents; HN pushback notes markdown-to-Dropbox already covers plain portability.
• dream-num/univer is an embeddable Office runtime (sheets, docs, slides, tables, PDF) with one Facade API, positioned as the productivity surface for agents to act on.
• anthropics/knowledge-work-plugins is Anthropic's open plugin repo that turns Claude Cowork into role-specific specialists, also usable in Claude Code.