Curbi / Pricing
Run the open-source checker locally, or connect your application to managed checks. Same configured rules. A clear price per reply.
Free Chrome Web Store companion or public MCP connection. No payment required.
Local + public tools
No signup for local checks or public MCP tools.
Hosted anonymous access is rate limited. Local execution uses your own resources.
Managed Check API
USD. Monthly usage billing through Stripe. $0 upfront for the usage subscription.
Each reply in a batch counts separately. Applicable taxes depend on billing location. No SLA or dedicated capacity is included.
Usage examples, excluding applicable taxes. A finding and a pass cost the same; invalid requests are not metered as completed checks.
| Checked replies / month | Usage charge |
|---|---|
| 1,000 | $1 |
| 10,000 | $10 |
| 100,000 | $100 |
Default ceilings are 100,000 checked replies per key and per shared billing customer per UTC month. A key can lower its own ceiling. These are checked-reply ceilings, not an account-wide spend cap: taxes, invoice adjustments and separate billing customers are excluded.
| What counts | One reply checked successfully. A batch of 20 replies counts as 20. |
|---|---|
| Retries | Reuse the same Idempotency-Key and request body to avoid another usage event. |
| Limits | 50 replies per request · 4,000 characters per reply · 64 KiB request body. |
| Key rate | 600 requests/minute per key. Published limits may still be constrained by service capacity. |
| Your data | Billing stores key hashes, subscription identifiers and usage records. It does not store your raw API key or reply text. |
Stripe returns you to Curbi in the same tab. Reveal and copy your private API key, then store it in your server’s secrets vault. Curbi verifies the current subscription before issuing the key.
Yes. Local checks and the six public read-only MCP tools remain available. A paid key is for the managed Check API.
No. Production action signing remains off. A configured rule check grants no execution permission and is not independent provider confirmation. Receipt examples use test keys.
Open Manage an existing subscription on the API access page. Your API key opens the Stripe billing portal for its customer. Cancellation is scheduled for the end of the billing period.
Try the checker now, then keep a failure as a runnable regression.
Managed API: $1 per 1,000 checked replies. Public tools have their own published limits: 64 KiB per check request; MCP is rate limited. See the API limits and MCP boundaries.
Choose an e-commerce, SaaS or support policy. Edit it, check a reply locally and optionally remember it on this device.
Choose a free policy profile →Connect your managed key to see current-key monthly counters, reserved capacity, completed checks and meter delivery states. Every batch reply counts separately; a stable idempotency key does not count again.
Ceilings apply atomically per key and shared billing customer. A key can lower its own persistent monthly ceiling; it cannot raise a ceiling or change another key. Setting zero stops new reservations. Completed usage and existing reservations remain.
GET https://api.curbi.io/v1/usage
Authorization: Bearer <key>
POST https://api.curbi.io/v1/budget
Authorization: Bearer <key>
Content-Type: application/json
{"monthlyBudget":1000}USD $0.001 per completed reply, before tax and invoice adjustments. Meter acceptance is asynchronous and is not a finalized invoice. Billing holds stop new checks while unconfirmed usage is reconciled.
Connect usage and set a lower ceiling →