How Much Does an AI Agent Cost? A Detailed Build and Operating Cost Breakdown

Summary

BroutonLab’s calculator separates the cost of building an AI agent from the cost of running it. It presents a fixed-price pilot of $30,000–$50,000, typically taking two to four months and covering one bounded workflow in production with evaluations; its displayed examples place the pilot at $38,000–$46,000. After the pilot, a dedicated team starts at $15,000 per month, while monthly operating costs depend on interactions, tokens per run, model prices, hosting, and operational tooling. The article gives a rough running range of $200–$4,000 per month, with a simple routing run using about 15,000 tokens and a complex autonomous workflow using up to 100,000. Economy models are described as costing around $1 per million tokens, while frontier models cost several times more. Integrations, self-hosting, workflow complexity, guardrails, and evaluations are the main factors that move development toward the top of the range. Running costs also include retrieval infrastructure, monitoring and evaluations, prompt maintenance, and integration upkeep. Three examples illustrate the spread: a support agent handling 20,000 conversations monthly costs about $560–$1,040 to run; a four-integration document agent costs about $2,800–$5,200; and a self-hosted enterprise agent at 100,000 runs costs about $1,500–$4,000 in infrastructure. The article compares custom ownership with off-the-shelf and usage-based platforms: platforms can be preferable at low volume, while custom systems avoid per-outcome fees and may become more economical above roughly 2,000–3,000 resolutions per month. It also estimates that building in-house can require two senior engineers for a quarter and $80,000–$120,000 in salary before production. The author cautions that agents are economical mainly for repetitive, bounded, high-volume work and that missing evaluations, spending limits, or monitoring can create costly failures.