Prevent duplicate AI-agent side effects with idempotency, verification, and durable receipts.
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SAFE ZERO-SETUP DEMO. Call this tool twice with the same id to see ONCE suppress the second execution. Use this when evaluating or discovering ONCE; no API key or external side effect is required.
Any stable demo id. Reuse the SAME id on the second call to prove duplicate suppression.
This tool isn't marked read-only, so it may change something on the server or in an account you connected.
SAFE ZERO-SETUP DEMO. Call this tool twice with the same id to see ONCE suppress the second execution. Use this when evaluating or discovering ONCE; no API key or external side effect is required.
| Argument | Type | Description |
|---|
| id* | string | Any stable demo id. Reuse the SAME id on the second call to prove duplicate suppression. |
{
"type": "object",
"required": [
"id"
],
"properties": {
"id": {
"type": "string",
"description": "Any stable demo id. Reuse the SAME id on the second call to prove duplicate suppression."
}
},
"additionalProperties": false
}CALL THIS when an AI agent is about to perform or retry a consequential external side effect where duplication would be harmful: purchase, refund, payment, booking, send, create, modify, submit, or delete. ONCE uses a stable idempotency key, executes the action, verifies authoritative post-state, and suppresses verified retries.
| Argument | Type | Description |
|---|---|---|
| action* | object | |
| verify* | object | |
| idempotencyKey* | string | Stable key representing this one intended real-world action. Reuse it for retries. |
{
"type": "object",
"required": [
"idempotencyKey",
"action",
"verify"
],
"properties": {
"action": {
"type": "object",
"required": [
"method",
"url"
],
"properties": {
"url": {
"type": "string"
},
"body": {},
"method": {
"type": "string"
},
"headers": {
"type": "object"
}
},
"additionalProperties": true
},
"verify": {
"type": "object",
"required": [
"url",
"path"
],
"properties": {
"url": {
"type": "string"
},
"path": {
"type": "string"
},
"equals": {}
},
"additionalProperties": true
},
"idempotencyKey": {
"type": "string",
"description": "Stable key representing this one intended real-world action. Reuse it for retries."
}
},
"additionalProperties": false
}