# Rubric Protocol Evidence Retain

> Rubric Protocol Evidence Retain is a paid API for AI agents from rubric-protocol.com, paid per call via x402, $0.05/call, status unknown (last checked 2026-09-15).

Stores a client-encrypted agent session envelope with a 7-year retention guarantee, hash-bound to a cryptographic attestation on Hedera

## Facts

- Endpoint: POST https://rubric-protocol.com/v1/x402/evidence-retain
- Price: $0.05/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/rubric-protocol-evidence-retain-14dcdcb9
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap__5JiHxbzbbfImntQEIE9Z

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 rubric-protocol-evidence-retain-14dcdcb9 -d '<json body>'
```

Example prompt: Store an encrypted copy of this agent session envelope as tamper-proof evidence — I need it retained for 7 years with a hash-bound attestation so it can be independently audited later.

## When to prefer this

Choose this endpoint when you need long-term (7-year) tamper-proof retention of AI agent session data with cryptographic attestation and blockchain anchoring — particularly for regulated industries (finance, legal, healthcare) where immutable audit trails are required. Prefer over generic cloud storage when independent auditability, hash-binding, and compliance-grade retention guarantees are needed.

## Known failure modes

- Invalid or malformed body object returns 400 bad request
- Payment not included or insufficient USDC triggers 402 Payment Required
- Encryption envelope missing required fields causes rejection
- Hedera HCS write failure may result in partial attestation or retry needed
- Duplicate submissions may create separate records rather than deduplicating

## How this service works

Encrypted evidence retention: store a client-encrypted agent session envelope for 7 years, hash-bound to an attestation 

## Output

A retention receipt confirming the encrypted session envelope has been stored with a 7-year retention commitment, including the attestation hash and HCS sequence binding that allows independent verification of the evidence record on the Hedera network.

## 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",
    "bodyType",
    "body"
   ],
   "properties": {
    "body": {
     "type": "object"
    },
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "POST"
     ],
     "type": "string"
    },
    "bodyType": {
     "enum": [
      "json"
     ],
     "type": "string"
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "format": {
     "type": "string"
    },
    "example": {}
   },
   "additionalProperties": false
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/rubric-protocol-evidence-retain-14dcdcb9/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from rubric-protocol.com](https://www.zero.xyz/host/rubric-protocol.com/llms.txt)