# Tereno Evidence Artifact

> Tereno Evidence Artifact is a paid API for AI agents from www.tereno.xyz, paid per call via x402, $0.01/call, status unknown (last checked 2026-09-15).

Retrieves or recomputes a provenance envelope for a public Tereno artifact, returning its source capability, field paths, validity window, and exact recomputation inputs.

## Facts

- Endpoint: GET https://www.tereno.xyz/api/v1/capabilities/evidence.artifact/invoke
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/tereno-evidence-artifact-5c72cb23
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_UUpYpBOG0hOVsNFwkfTHF

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 tereno-evidence-artifact-5c72cb23
```

Example prompt: Check whether this Tereno artifact sha256:3a7b1c2d4e5f6a8b9c0d1e2f3a4b5c6d7e8f9a0b1c2d3e4f5a6b7c8d9e0f1a2b can be reused and give me its provenance details, including the source capability and how long it's valid for.

## When to prefer this

Use this endpoint when another Tereno agent or capability has returned an artifactId and you need to determine if that result can be safely reused, understand its provenance, or automatically refresh it if expired — all in a single call. Prefer this over calling the original source capability directly when you already have an artifactId and want to avoid redundant computation and cost.

## Known failure modes

- Invalid or malformed artifactId (not matching sha256:[a-f0-9]{64} pattern) returns a validation error
- Private or non-public artifact returns a rejection (private transaction intent blocked)
- Artifact source capability is unavailable for recomputation, returning a service error
- Expired artifact whose source recomputation also fails returns a stale/error response
- Missing required artifactId query parameter returns a 400 error
- Invalid quote id causes payment or authorization failure

## How this service works

Can this public Tereno artifact be reused? Return a typed provenance envelope with source capability, field paths, validity window and exact recomputation input. If the artifact has expired, its source is recomputed in place and the fresh answer ships inside the same response. Private transaction intent is rejected. Use when another agent gives you a Tereno artifactId.

## Output

A typed provenance envelope containing: the source capability ID, covered field paths, validity window (validUntil), exact recomputation inputs, an optional 'refreshed' object if the artifact had expired and was recomputed on-the-fly, a verdict (allow/review/block), an invocation ID, and a receipt URL. If expired, the refreshed result's validUntil governs the payload.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "artifactId"
     ],
     "properties": {
      "quote": {
       "type": "string",
       "description": "Optional single-use quote id."
      },
      "artifactId": {
       "type": "string",
       "pattern": "^sha256:[a-f0-9]{64}$",
       "description": "Public reusable artifact id returned by another Tereno capability."
      }
     },
     "additionalProperties": false
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "required": [
      "capabilityId",
      "result",
      "pricing",
      "receiptUrl"
     ],
     "properties": {
      "result": {
       "type": "object",
       "properties": {
        "refreshed": {
         "type": "object",
         "description": "Present only when the artifact had expired and its source was recomputed in place. Its validUntil governs the payload."
        }
       }
      },
      "pricing": {
       "type": "object"
      },
      "verdict": {
       "enum": [
        "allow",
        "review",
        "block"
       ]
      },
      "receiptUrl": {
       "type": "string"
      },
      "capabilityId": {
       "const": "evidence.artifact"
      },
      "invocationId": {
       "type": "string"
      }
     }
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/tereno-evidence-artifact-5c72cb23/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from www.tereno.xyz](https://www.zero.xyz/host/www.tereno.xyz/llms.txt)