If you've been building AI agents seriously, you've hit this wall: your agent can browse the web, write code, send emails — but the moment it needs to pay for something, you're back to hardcoding API keys, managing credit card credentials in environment variables, and praying nothing goes wrong at 3am. That's not a niche problem. That's a fundamental gap in the agentic stack. FluxA is the payment infrastructure layer built specifically to close it. After spending time exploring and testing it, here's a practical breakdown of what it does, what makes it different, and why it matters for developers building agents in 2025 and beyond. The Core Problem: Agents Can't Handle Money Safely Most current setups fall into one of two failure modes: No payment capability at all — the agent hits a paywall and stops, forcing manual intervention. Shared credentials — the agent uses your personal API key or credit card with zero guardrails, zero audit trail, and full blast radius if something goes wrong.…