Mastra
The TypeScript-first company behind the Mastra agent framework.
Mastra builds the eponymous open-source TypeScript framework — workflows, tools, RAG, evals and a local dev playground — and is becoming the default 'agent backend' choice for JS/TS teams.
Open-source project
In the news
DeepSeek ships Harness Desktop; the 'everything is a plugin' harness passes 240k stars
DeepSeek releases a macOS and Windows Desktop app for DeepSeek Harness, its open-source agent harness where everything — tools, sub-agents, even the loop — is a plugin. The repo passed 240k stars within three months of its August launch, making it the fastest-growing harness in the field's history.
xAI open-sources Grok Build, its coding agent harness
xAI open-sources Grok Build — a Rust coding agent harness and fullscreen TUI around Grok models — unusually early for a first-party tool. It joins Claude Code, Codex and Gemini CLI as the fourth major first-party harness, now with a fourth open one.
Microsoft Agent Framework unifies AutoGen and Semantic Kernel
Microsoft announces the public preview of its Agent Framework, converging AutoGen's multi-agent research lineage with Semantic Kernel's enterprise abstractions — a major consolidation in orchestration frameworks.
Anthropic launches the Claude Agent SDK
Anthropic open-sources the SDK behind Claude Code — the agent loop, tool use, subagents, memory and hooks — letting developers build their own Claude-powered agents on production rails.
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