# Anchor X402 Academic Grader

> Anchor X402 Academic Grader is a paid API for AI agents from api.anchor-x402.com, paid per call via x402, $0.01/call, status unknown (last checked 2026-09-13).

Assigns an academic letter grade with red-pen marginalia commentary to any submitted text or content, for $0.01 USDC via x402 payment.

## Facts

- Endpoint: POST https://api.anchor-x402.com/v1/grade
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-13
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/api-anchor-x402-com-1ef335f2
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_5Nx4XX2BFVExfFqWEzFUe

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 api-anchor-x402-com-1ef335f2 -d '<json body>'
```

Example prompt: Give this essay a letter grade with red-pen marginalia like a strict professor would: 'The industrial revolution fundamentally reshaped society by accelerating urbanization and displacing agrarian lifestyles. While technological progress improved material conditions, it simultaneously created exploitative labor conditions and environmental degradation.'

## When to prefer this

Use this endpoint when you need human-readable academic-style feedback with a letter grade on any text, writing, code, or argument. Ideal for evaluating drafts, essays, proposals, or any content requiring qualitative critique with the feel of a professor's red pen. Prefer this over generic summarization or sentiment analysis when structured academic grading with inline commentary is the desired output format.

## Known failure modes

- Empty or missing content body returns validation error
- Content too long may be truncated or rejected
- Payment failure via x402 returns 402 Payment Required
- Ambiguous or non-textual input may yield low-confidence grading
- Rate limiting if too many requests in a short window

## How this service works

Academic letter grade with red-pen marginalia for anything. $0.01 USDC.

## Output

Returns an academic letter grade (A through F) along with red-pen style marginalia — inline annotations and commentary critiquing the submitted content as a professor or teacher would mark up a student submission.

## Example request

```json
{
 "target": "The rapid advancement of artificial intelligence has transformed industries and created new opportunities for innovation. However, concerns about job displacement and algorithmic bias remain significant challenges that society must address through thoughtful regulation and ethical frameworks."
}
```

## 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",
      "PUT",
      "PATCH"
     ]
    },
    "bodyType": {
     "type": "string",
     "enum": [
      "json",
      "form-data",
      "text"
     ]
    },
    "body": {
     "properties": {
      "target": {
       "type": "string",
       "description": "Anything to grade.",
       "maxLength": 6000
      }
     },
     "required": [
      "target"
     ]
    }
   },
   "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": {
  "summary": "Strong vibes, weak math. See me after class.",
  "marginalia": [
   "Function name says 'add' but operator says 'subtract' — pick a side.",
   "The comment is the funniest thing in this codebase.",
   "Add a test and your subconscious will thank you."
  ],
  "letter_grade": "D"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/api-anchor-x402-com-1ef335f2/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.anchor-x402.com](https://www.zero.xyz/host/api.anchor-x402.com/llms.txt)