# OwlKey AI Writing API

> OwlKey AI Writing API is a paid API for AI agents from www.owlkeyapi.com, paid per call via x402, $0.003/call, status unknown (last checked 2026-09-14).

Generates AI-written copy including launch copy, social posts, summaries, hooks, and text variants from a prompt, tone, format, and audience specification.

## Facts

- Endpoint: POST https://www.owlkeyapi.com/x402/services/write
- Price: $0.003/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/owlkey-ai-writing-api-40abe51d
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_45xdNwKB3RUyleYpJ_VMV

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 owlkey-ai-writing-api-40abe51d -d '<json body>'
```

Example prompt: Write me a playful social media post for my app launch targeting indie developers — keep it brief and punchy, like a Twitter announcement.

## When to prefer this

Choose this endpoint when an agent needs fast, low-cost AI-generated marketing or content copy — especially launch copy, social posts, summaries, hooks, or ad text — and wants control over tone, format, and audience without building a full LLM pipeline. At $0.003 per call it is cost-efficient for high-volume content generation tasks in agentic workflows.

## Known failure modes

- Prompt too short or missing (minLength:1 violation) returns validation error
- Prompt exceeds 4000 characters returns a length validation error
- Ambiguous or conflicting tone/format instructions may yield generic or mismatched output
- Insufficient USDC balance causes payment failure via x402 protocol
- Unsupported tone or format values may be silently ignored or default to neutral output

## How this service works

Low-cost AI writing API for agents. Generates launch copy, posts, summaries, hooks, and reusable text variants.

## Output

Returns AI-generated text content matching the specified format, tone, and audience — such as a social post, summary, email body, ad copy, or hook — based on the provided writing prompt.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "tone": {
   "type": "string",
   "description": "Optional tone, such as clear, direct, premium, or playful."
  },
  "format": {
   "type": "string",
   "description": "Optional output format, such as brief, post, summary, email, or ad."
  },
  "prompt": {
   "type": "string",
   "maxLength": 4000,
   "minLength": 1,
   "description": "Writing task or source material."
  },
  "audience": {
   "type": "string",
   "description": "Optional target audience."
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/owlkey-ai-writing-api-40abe51d/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from www.owlkeyapi.com](https://www.zero.xyz/host/www.owlkeyapi.com/llms.txt)