Cheaper tokens, bigger bills: the economics of scaling AI agents
A blog article written by Zowie. The company is Community Partner at Banking 4.0.
Every enterprise running agentic AI in production is watching the same number climb. Unfortunately, it’s not accuracy and not a resolution rate. What constantly goes up is the bill.
Token prices for GPT-4-class work fell from $30 per million tokens in 2023 to $0.10 per million tokens in 2026, a 280x drop, according to Epoch AI’s benchmark tracking. Over the same two years, the average enterprise AI budget rose from $1.2 million a year to $7 million (AnalyticsWeek’s 2026 Inference Economics report). Inference, the ongoing cost of running a model to answer real requests now eats 85% of that budget alone. Prices kept falling, but usage grew even faster. Cheaper tokens ↔ bigger bills.
It’s more cost effective to invest in agentic AI that relies on a Decision Engine than in agentic AI that routes every decision through a model. Here’s why.
Cheaper tokens, bigger bills
The very first thing is the agentic loop. Gartner’s March 2026 analysis found agentic workflows consume 5 to 30 times the tokens of a single chatbot exchange, because a workflow that plans, calls tools, checks its own output, and retries pays for a model call at each of those steps. An exchange that used to run on 2,000 tokens can turn into 50,000 or more for a single business transaction. The always-on monitoring agents are now run continuously by most enterprises. It’s no surprise the FinOps Foundation’s 2026 State of FinOps Report names AI the fastest-growing line item in enterprise spend, with 73% of teams reporting costs that exceeded their original projections.
Why routing to smaller models
The industry’s answer is model routing: classify each step by how hard it actually is, send the easy, repetitive majority (parsing a command, extracting a field, formatting a reply, tagging an intent) to a small model that costs a fraction of a frontier one, and reserve the frontier model for the ambiguous minority that needs real power. As NVIDIA’s research team stated: small language models are “sufficiently powerful, inherently more suitable, and necessarily more economical” for most of what an agent is supposed to do.
The math backs it up. Engineering firm Lushbinary walked through a representative case: an agent handling a million routine calls a day, on a frontier model priced around $5 per million input tokens and $25 per million output tokens, runs close to $675,000 a month. If you move the same routine work to a self-hosted small model, the bill could drop by one to two orders of magnitude. Now that’s a real fix. And most serious agent platforms are already doing some version of it.
Routing still bills every decision
Routing to smaller models doesn’t make a decision free. It only makes it cheaper. Every model, large or small, works the same way: it predicts the most likely answer based on patterns in its training data, rather than following a fixed set of rules. That means every routed step still costs money per use, and still carries a small chance of getting the answer wrong – even with a well-trained small model. That’s a fine trade for summarizing a support ticket or pulling an order number, where a rare mistake is cheap to fix. But it’s a completely different bet for a refund decision or a compliance-sensitive eligibility check, where you can’t be “usually right”. The bar is being always right. And no model, large or small, can promise that.
Rare cases are the expensive ones
Most of what an AI agent handles is a small set of common requests, repeated the same way thousands of times a day. The long tail is everything else: the policy exception that only applies in one market, the eligibility rule tied to a product line discontinued two years ago. A routed system pays for these twice. First in the tokens the router itself spends deciding which model should handle each new case. Second in the escalations, because the long tail is exactly where confidence runs lowest, which means it’s exactly where the cheap model bails and the expensive one gets the call anyway. So the cost curve that was supposed to flatten with a good router instead bends upward right where the business value, and the cost of getting it wrong, is highest.
Read the article in full here
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