Harness Engineering 101 presents a practical thesis: large language models are the "brain" while the harness - the program that builds, maintains, and protects the conversation array - is the "body" that makes agents work. It treats every agent feature as a concrete patch to a single synchronous request/response loop (you send a JSON array of turns and get text back), and develops that idea through 16 chapters that repeatedly follow a pattern: the failure, a minimal patch, and the patch's costs. The book grows a runnable ~300-line toy harness in plain Python, covering fundamentals like tools-as-JSON-mapped-functions, the agent loop, caching, context budgeting, subagents, steering long-running tasks, background work, and debugging, then expands to ecosystem and trust topics such as capabilities extension (MCP/skills), guardrails, coding-agent case studies, and reframing RAG as a harness pattern.
The project includes full source, diagrams, build instructions for mdBook, and scripts to regenerate quantitative diagrams, plus a clear repository layout with src/harness implementations. Appendices address advanced patterns - model routing and cost engineering, parallel worktrees, mode enforcement, and retries/rate limits/streaming. Prose is licensed CC BY-NC-ND; code is MIT. Version 1.0 (Sept 2026) by Isuru Wijesiri provides both conceptual framing and concrete, runnable patterns for anyone who wants a principled, incremental approach to building robust AI agents.
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Company World Models are AI systems designed to observe business activities, generate strategic hypotheses, and coordinate actions through digital employees to improve company performance. They aim to enable better decision-making and growth for essential businesses by integrating AI as a strategic partner. (beaconholdings.com)
Cloudflare introduces Clairic, a new class of extraction models within the System One framework. The development aims to improve data extraction capabilities for various applications. (blog.cloudflare.com)
Mercury 3 is the most advanced diffusion-based large language model, outperforming models like GPT-6 Luna and Claude Haiku 5.5 in speed and capabilities, processing over 1,000 tokens per second. It is already used for real-time applications such as web navigation, voice support, and education, demonstrating that diffusion models can scale effectively for commercial use. (inceptionlabs.ai)
Grok Bot processes messages using distributed systems components like queues, workflows, and caching to ensure responsiveness and reliability. When a user sends a message, it is immediately shown locally, then queued and handled with priority, with the system maintaining state and recovering from crashes using Temporal. (peterp.me)
Software has revolutionized industries, and AI is now deeply integrating into software development processes. Future advancements are expected as AI continues to evolve and embed itself further in technology. (medium.com)
MiniMax M3.1 Flash is a next-generation AI model that offers three times faster online inference and reduces costs by 70%. It excels in complex tasks such as agentic workflows, coding, cybersecurity, and real-world automation. (minimax.io)
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