SpendCap: Budget circuit breaker for coding agents

Hard spending caps for autonomous coding agents to prevent auto-recharge and bill surprises

Problem

People running autonomous coding agents worry about agents spending real money on API credits, cloud resources, domains, or SaaS; stories of auto-recharge and bill surprises circulate in the community. Users want to know how others cap agent spending, but there is no lightweight tool to set budgets before calls and trip a breaker on overrun.

Solution

A local proxy or SDK wrapper that intercepts an agent's paid calls to external services and enforces hard budgets per task or per day. When a threshold is exceeded it blocks the call and notifies the user, while logging every expense the agent incurs. Integrates with common APIs and cloud services and outputs per-session cost reports.

Users

Developers running autonomous coding agents, solo maintainers using agents for auto-deploy, small team tech leads

MVP

Call interception and budget config; auto-block and notify on overrun; per-session/per-day expense log; integration with 2-3 common paid APIs;

Revenue

Open-source core plus hosted dashboard subscription; team tier priced by agent count

Why now

Autonomous agents are starting to spend real money, but cloud and API platforms won't build fine-grained breakers for individuals; the tooling gap is open for indie developers.