The Agent Stack

The Agent Stack #034 — Monday Build You don’t need a framework to build an AI agent. You need 300 lines of Python and a clear head about what ReAct actually does. This week’s most practical piece came from quantumentangled.dev - a walkthrough of ReAct’s core loop without the enterprise bloat. I’ve been saying this for months: most agent frameworks are solving problems you don’t have yet. The 300-Line Reality Check ReAct (Reasoning + Acting) boils down to three steps: ...

The Agent Stack #033 — Friday Signal The AI infrastructure market just got real validation. Cerebras raised £4.3B in their IPO this week, with shares jumping 108% on debut. Hardware becomes the new moat Cerebras makes wafer-scale processors designed specifically for AI training. Their IPO success proves investors believe specialised AI chips will dominate general-purpose GPUs. The stock pop shows demand for alternatives to NVIDIA’s stranglehold on AI compute. This matters for agent builders. Training costs have been the biggest barrier to custom models. Cerebras promises 20x faster training at lower power consumption. If they deliver, we’ll see more companies building domain-specific agents instead of relying on OpenAI’s general models. ...

The Agent Stack #032 — Wednesday Stack The agent tooling space loves to debate skills vs documentation. Wix Engineering just settled it with actual data. The Skills vs Docs Battle Wix ran 250 evaluations comparing agent performance with two approaches: traditional documentation retrieval versus structured “skills” (function calls). The results? Skills won 67% of the time, but the gap wasn’t as wide as expected. Their test setup was proper production-grade. They used GPT-4 as the judge, tested across multiple domains (e-commerce, content management, user authentication), and measured both accuracy and execution time. Each eval ran against the same underlying API operations—just packaged differently. ...

The Agent Stack #031 — Monday Build MachinaCheck just dropped something interesting. A multi-agent system for CNC manufacturability analysis running on AMD’s MI300X accelerators. This isn’t another ChatGPT wrapper—it’s proper industrial AI that could change how we validate designs before they hit the factory floor. The Architecture That Actually Works The MachinaCheck team built three specialised agents working in concert. First agent analyses CAD geometry for basic manufacturability. Second agent simulates toolpath generation and identifies potential issues. Third agent estimates costs and lead times based on real manufacturing constraints. ...

The Agent Stack #030 — Friday Signal OpenAI just handed every agent builder a microphone. The new voice intelligence features in their API mean your agents can now hear, speak, and respond in real-time conversations. This isn’t just text-to-speech with extra steps. The API now includes real-time voice streaming, conversation detection, and audio processing that works across different accents and languages. OpenAI’s specifically targeting customer service systems, education platforms, and creator tools. ...

The Agent Stack #029 — Wednesday Stack OpenAI just dropped GPT-5.5 Instant as ChatGPT’s new default model. The company claims it cuts hallucinations “significantly” across law, medicine, and finance whilst keeping the same low latency as GPT-4o. I’ve been testing it for 72 hours on production workloads. Here’s what actually changed. The Reality Check OpenAI’s internal benchmarks show factuality improvements across their eval suites. But internal evals are like dating profiles - technically accurate but missing crucial context. ...

The Agent Stack #028 — Monday Build The Pentagon just gave us the biggest signal yet about where AI agents are heading. Last Friday, they signed deals with OpenAI, Google, Microsoft, AWS, Nvidia, and xAI to deploy AI on classified networks. Anthropic got left out over usage disputes. This isn’t just procurement news - it’s your blueprint for building enterprise-grade agents that handle sensitive data. Why This Matters for Builders Government contracts always preview enterprise requirements 18 months early. The Pentagon’s criteria tell us exactly what Fortune 500 CISOs will demand: ...

The Agent Stack #027 — Friday Signal Anthropic is asking investors for allocation decisions within 48 hours for a funding round that could value the company at $900 billion (£720B). That’s not a typo. The mega-round that breaks AI economics This isn’t just another funding round. It’s a statement that foundation model companies are now valued like sovereign wealth funds. For context, £720B is larger than the GDP of most countries. ...

The Agent Stack #026 — Wednesday Stack Tank OS just landed and it’s the first enterprise-grade solution I’ve seen that actually addresses the “Claude deleted our database” problem. After watching five documented agent failures in 36 days (with zero self-detection), Red Hat’s new containerisation approach for OpenClaw deployments isn’t just timely—it’s essential. I’ve been testing Tank OS for three weeks in our staging environment. Here’s what actually works and what doesn’t. ...

The Agent Stack #025 — Monday Build Distributed tracing just got its AI moment. Jaeger v2 dropped with OpenTelemetry at its core, specifically targeting the chaos of multi-agent workflows. The timing isn’t coincidental. Traditional observability breaks down when you have agents calling other agents calling APIs calling more agents. You end up with a mess of logs that tell you nothing about why your agent decided to delete the production database (yes, that actually happened this week). ...