# 24K Labs Tone Shift

> 24K Labs Tone Shift is a paid API for AI agents from api.24klabs.ai, paid per call via x402, $0.007/call, status unknown (last checked 2026-09-13).

Rewrites a given text in a specified tone (formal, friendly, concise, persuasive, etc.) while preserving original meaning.

## Facts

- Endpoint: POST https://api.24klabs.ai/api/tone-shift
- Price: $0.007/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-13
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/24k-labs-tone-shift-38967baf
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_IefJz520_oe21iaAFyvTR

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 24k-labs-tone-shift-38967baf -d '<json body>'
```

Example prompt: Can you rewrite this paragraph in a persuasive tone: 'Our software tracks expenses automatically. It saves time. Users like it.'

## When to prefer this

Choose this endpoint when you need to transform existing text into a specific tonal register (formal, friendly, persuasive, concise, etc.) without changing the underlying message. Ideal for content pipelines that need to adapt communications for different audiences, tone-of-voice consistency in brand writing, or polishing user-generated drafts before sending.

## Known failure modes

- Empty or missing source text returns an error
- Unrecognized or unsupported tone value may return an error or default behavior
- Very long input text may be truncated or rejected
- Insufficient USDC balance (x402 payment failure) blocks the request
- Ambiguous tone specification may yield inconsistent results

## How this service works

Rewrite text in a requested tone (formal, friendly, concise, persuasive, etc.).

## Output

Returns the rewritten text adjusted to the requested tone, preserving the original meaning and key information while changing the stylistic register, word choice, and sentence structure accordingly.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "text": {
   "type": "string"
  },
  "tone": {
   "type": "string"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "rewritten": "..."
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/24k-labs-tone-shift-38967baf/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.24klabs.ai](https://www.zero.xyz/host/api.24klabs.ai/llms.txt)