Usage-based billing & quota enforcement for x402

[Miracle656]

Background

x402 enables per-call payment, but operators need metering, quotas, and billing to run it as a paid service.

What to build

Meter paid requests per API key, enforce configurable quotas/rate tiers, and expose a usage/billing summary endpoint. Build on the existing x402 middleware rather than replacing it.

Key files

• src/x402/metering.ts (new)
• src/api/usage.ts (new)

Acceptance criteria

• Each paid call metered against the key's quota
• Over-quota requests handled per policy (block / 402 / overage)
• Usage summary endpoint + tests

Drips Wave · Complexity: Advanced · 200 points

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[teethaking]

@teethaking has applied to work on this issue as part of the Stellar Wave Program's 6th wave.

hello maintainer may i work on this issue?
ill submit PR within 1-3 days

ℹ️ Repo Maintainers: To accept this application, review their application or assign @teethaking to this issue.

[Codex723]

@Codex723 has applied to work on this issue as part of the Stellar Wave Program's 6th wave.

I have experience building usage metering systems on top of existing middleware, including per-API-key request tracking, configurable quota enforcement with block/402/overage policies, and usage summary endpoints with tests. I'm ready to implement metering.ts and usage.ts on top of the existing x402 middleware without replacing it, covering all quota tiers and the billing summary endpoint.

ℹ️ Repo Maintainers: To accept this application, review their application or assign @Codex723 to this issue.

[fadesany]

@fadesany has applied to work on this issue as part of the Stellar Wave Program's 6th wave.

Hello maintainer, i would like to work on this issue

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[tecch-wiz]

@tecch-wiz has applied to work on this issue as part of the Stellar Wave Program's 6th wave.

Hi, I’m interested in working on this issue. I have experience with web and blockchain development, and I’d love to contribute to the project. Please assign this issue to me if it’s available. Thanks!

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[drips-wave]

Congratulations, @teethaking! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on June 30, 2026.

🧑‍💻 @teethaking: Please resolve the issue such that the repo's maintainers have enough time to review your contribution before the due date. You'll earn Points for completing the issue on-time, which will make you eligible for a share of the Stellar Wave Program's reward pool.

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