bugiiiii11/rein
by Various
Spend limits for AI agents that pay with x402: every paywall is policy-checked (per-call caps, budgets, human appr
MCP
bugiiiii11/rein
Added 18 Oct 2026
Overview
Rein is a TypeScript library that enforces spend limits for AI agents paying through x402. It applies policy checks to every paywall, supporting per-call caps, budgets, and human approval workflows.
Best for
Best for
Developers building AI agents that need controlled spending on x402 paywalls
Use cases
- Cap per-call spending for AI agents
- Set overall budgets for agent payments
- Require human approval for large paywall charges
Notes
0 stars on GitHub. Last updated 2026-10-18. Licensed MIT.
Pros
- Enforces per-call caps and budgets
- Includes human approval flow
- Available on GitHub
Cons
- No stars yet, suggesting early stage
- Limited adoption evidence
- Scope limited to x402 payments
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