What factors determine AI coding agent development cost?

[Ana]

What factors have the biggest impact on AI coding agent development cost?

Beyond the initial development, how much do AI model usage, codebase complexity, integrations, security, and autonomous capabilities affect the overall investment?

Also, what ongoing costs should be considered, such as API usage, infrastructure, maintenance, and monitoring?

Would be interested in hearing practical experiences or estimates from anyone who has worked on AI coding agents.