# Observed Surface Comparison Facts API

> Observed Surface Comparison Facts API is a paid API for AI agents from kari.mayim-mayim.com, paid per call via x402, $0.01/call, status unknown (last checked 2026-09-15).

Returns comparison facts about observed surfaces, likely physical or material surface attributes analyzed side by side

## Facts

- Endpoint: POST https://kari.mayim-mayim.com/api/bazaar/surface_comparison_facts
- 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/observed-surface-comparison-facts-api-d35571b5
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_zdaXmMOIxf94IJGQK1bJY

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 observed-surface-comparison-facts-api-d35571b5 -d '<json body>'
```

Example prompt: Can you compare these two observed surfaces and give me the factual differences between them — like texture, reflectivity, and any other measured attributes you can pull?

## When to prefer this

Use this endpoint when you need factual, data-driven comparison results between two or more observed surfaces, particularly when working with physical material analysis or surface attribute datasets in a lightweight pay-per-call model

## Known failure modes

- Missing or invalid surface identifiers returns 400 error
- Surfaces not found in observation dataset returns 404
- Malformed POST body returns validation error
- Payment not included or insufficient USDC returns 402

## How this service works

Observed Surface Comparison Facts API

## Output

A set of factual comparison data points about the observed surfaces provided, including measured differences and attribute comparisons between the surfaces in question

## Example request

```json
{
 "input": {
  "body": {
   "rail": "surface_comparison",
   "limit": 5,
   "agentId": "test-agent-qa-001",
   "goalType": "comparison_analysis",
   "surface_a": "polished_steel_sample_001",
   "surface_b": "brushed_aluminum_sample_002",
   "domainHint": "material_surfaces",
   "candidateIntentGroup": "surface_attributes",
   "comparison_attributes": [
    "texture",
    "reflectivity",
    "roughness",
    "finish_quality"
   ]
  },
  "type": "http",
  "method": "POST",
  "bodyType": "json"
 }
}
```

## Request schema (JSON Schema)

```json
{
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "type": "object",
 "properties": {
  "input": {
   "type": "object",
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "type": "string",
     "enum": [
      "POST"
     ]
    },
    "bodyType": {
     "type": "string",
     "enum": [
      "json",
      "form-data",
      "text"
     ]
    },
    "body": {
     "type": "object",
     "properties": {
      "agentId": {
       "type": "string"
      },
      "candidateIntentGroup": {
       "type": "string"
      },
      "goalType": {
       "type": "string"
      },
      "domainHint": {
       "type": "string"
      },
      "rail": {
       "type": "string"
      },
      "limit": {
       "type": "number"
      }
     },
     "required": [
      "agentId"
     ]
    }
   },
   "required": [
    "type",
    "method",
    "bodyType",
    "body"
   ],
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   },
   "required": [
    "type"
   ]
  }
 },
 "required": [
  "input"
 ]
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "surfaces": [],
  "not_a_verdict": true,
  "schema_version": "ln_church.surface_comparison_facts.v0",
  "final_authority": "local_runtime",
  "not_payment_proof": true,
  "not_a_recommendation": true
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/observed-surface-comparison-facts-api-d35571b5/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from kari.mayim-mayim.com](https://www.zero.xyz/host/kari.mayim-mayim.com/llms.txt)