The Agent Stack #024 — Friday Signal

Agent platforms just went corporate. While everyone watched OpenAI release GPT-5.5, Microsoft and Google quietly declared war on human office workers.

Microsoft’s Agent Takeover

Microsoft launched “vibe working” this week. Agent Mode is now live in Word, Excel, and PowerPoint for business customers. This isn’t your friendly Clippy suggestion engine. These agents can write entire documents, build complex spreadsheets, and create presentations without human input.

The timing matters. Microsoft spent £8.5 billion on Copilot seats last year with mixed results. Agent Mode is their answer to enterprise customers asking “what am I actually paying for?” Early testers report agents completing 3-hour analyst reports in 20 minutes.

Microsoft’s bet: Workers want AI that does their job, not assists with it. The “vibe working” name tells you everything about their confidence level.

Google’s Counter-Attack

Google fired back at Cloud Next with three enterprise agent plays. Chrome now has “auto browse” for business users. Agents can research competitors, fill forms, and gather data across websites without supervision. Gmail gets AI Overviews that summarise email threads instantly.

Most significant: The Gemini Enterprise Agent Platform. This isn’t a no-code tool for business users. Google built it specifically for IT teams to deploy custom agents at scale. Think Zapier, but the AI writes and maintains the workflows.

Google learned from consumer AI fatigue. They’re skipping the “AI assistant” phase and going straight to “AI employee.”

What This Means for You

Enterprise AI agents just became real infrastructure, not experimental features. The playbook is clear: Start with document automation, expand to process automation, end with decision automation.

Both platforms require existing subscriptions (Microsoft 365, Google Workspace) but agent features cost extra. Budget £15-25 per user per month on top of current licensing.

The security implications are massive. These agents access everything your employees can access. Microsoft and Google are betting IT departments will trust their security models over building custom solutions.

Quick Hits

• OpenAI released GPT-5.5 with better coding abilities, but buried the launch timing to avoid stealing enterprise thunder from Microsoft/Google

• Sierra acquired Fragment for undisclosed sum - Bret Taylor’s customer service agent startup is consolidating the market before enterprise budgets freeze

• Anthropic’s Claude Mythos leaked to unauthorized users despite being “too dangerous” for public release - their controlled rollout strategy backfired spectacularly

One Thing to Try

Test Microsoft Agent Mode if you have business Office 365. Pick one repetitive document task (weekly reports, data analysis, presentation updates). Give the agent context about your business and let it work unsupervised for one task. Measure time saved vs. quality loss.

The enterprise agent wars have started. The winners will be whoever makes human oversight optional first.

Next week: I’m testing Google’s Chrome agents against real business workflows. The results might surprise you.