# CYRE Guardian Circuit Breaker Seal

> CYRE Guardian Circuit Breaker Seal is a paid API for AI agents from cyre.dev, paid per call via x402, $0.003/call, status unknown (last checked 2026-09-14).

Seals a signed circuit-breaker token that binds an agent's heartbeat interval and spend rails, enabling downstream heartbeat and pre-payment enforcement checks.

## Facts

- Endpoint: GET https://cyre.dev/api/circuit/seal
- Price: $0.003/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/cyre-guardian-circuit-breaker-seal-fddffebe
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_vgUvBjg6wdUsyI3EE-exD

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability cyre-guardian-circuit-breaker-seal-fddffebe
```

Example prompt: Set up a CYRE Guardian circuit breaker seal for my agent at actor address 0xABC123, with a max spend limit of 5000000 atomic units, so its heartbeat and payment rails are locked in before it starts operating.

## When to prefer this

Use this endpoint at agent initialization time, before the agent begins its operational loop or makes any payments. It is the required first step in the CYRE Guardian circuit-breaker flow — without a sealed token, the heartbeat and pre-payment check endpoints cannot enforce spend limits. Prefer this over ad-hoc spend limit approaches when you need a cryptographically signed, tamper-evident policy that downstream checks (heartbeat, pay-check) can verify trustlessly.

## Known failure modes

- Missing or invalid 'actor' query parameter returns an error and no token is issued
- Invalid HTTP method (only GET/HEAD/DELETE accepted) results in a 405 or schema validation error
- Malformed maxSpendAtomic value (non-numeric string) may cause policy sealing to fail
- Calling seal again for the same actor may overwrite or conflict with an existing circuit token
- Network or payment failure ($0.003 USDC x402 charge not settled) results in no token being issued

## How this service works

Guardian Circuit Breaker — seal operator heartbeat interval + spend rails for an autonomous agent. Heartbeat via /api/circuit/heartbeat; enforce before pay via /api/circuit/check. Patterns, not verdicts. Agent guide: https://cyre.dev/SKILL.md

## Output

Returns a signed circuit-breaker token that encodes the actor's heartbeat interval and spend policy seal. This token must be used in subsequent /api/circuit/heartbeat calls to prove the agent loop is alive, and presented to /api/circuit/check before any payment to enforce the sealed spend rails.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET",
      "HEAD",
      "DELETE"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "actor"
     ],
     "properties": {
      "actor": {
       "type": "string"
      },
      "maxSpendAtomic": {
       "type": "string"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/cyre-guardian-circuit-breaker-seal-fddffebe/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from cyre.dev](https://www.zero.xyz/host/cyre.dev/llms.txt)