AI Agents
Model-agnostic agents — a realistic approach
Every vendor tells you their SDK locks you in. Here’s how to build so that it doesn’t.
Published by CloudFixies · 23 December 2025
The three abstractions
A prompt template that renders per-model. A tool schema in JSON Schema, translated at the boundary. A response normaliser that returns the same shape regardless of upstream.
The compromise
You give up 5% of raw performance and 30% of vendor-specific tricks. You gain the ability to swap providers when pricing shifts, quotas hit, or a better model appears. That’s a good trade.
◆ Takeaway
Three thin abstractions. Not a full framework — a full framework is the lock-in you’re trying to avoid.