# Delx Ext From MIME

> Delx Ext From MIME is a paid API for AI agents from api.delx.ai, paid per call via x402, $0.001/call, status unknown (last checked 2026-09-15).

Returns the canonical file extension for a given MIME type using a local, first-party JSON lookup.

## Facts

- Endpoint: POST https://api.delx.ai/api/v1/x402/ext-from-mime
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/delx-ext-from-mime-c88742ee
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_3lXY6b6J0503lrUUbKXlJ

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 delx-ext-from-mime-c88742ee -d '<json body>'
```

Example prompt: I just got a file back with content-type 'image/webp' and need to know what file extension to save it with — can you look that up?

## When to prefer this

Use this endpoint when an AI agent needs to programmatically determine the correct file extension from a MIME/content-type string — especially when saving, naming, or routing agent-generated or downloaded files. Prefer it over regex guessing or hardcoded maps because it uses a maintained, first-party local JSON source with a known flag to signal confidence. It requires no external network calls, no API keys, and has no data retention, making it safe for pipeline use.

## Known failure modes

- Unrecognized MIME type returns known: false with a best-guess or null extension
- Malformed or missing mime field returns a validation error
- Payment failure via x402 prevents the call from executing

## How this service works

Guess extension from MIME type. Call when you name agent-generated files from content-type. Returns ext, mime, known for $0.001 USDC via x402 on Base. No network, no keys, no retention; first-party local JSON only. Results are advisory; the caller owns budgets, auth, and production controls.

## Output

Returns a JSON object containing the resolved file extension (ext), the canonical MIME type (mime), and a boolean (known) indicating whether the MIME type was recognized in the local lookup table.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "mime": {
   "type": "string",
   "description": "Input field: mime."
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "ext": "png",
  "mime": "image/png",
  "known": true,
  "schema": "delx/util-ext-from-mime/v1"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/delx-ext-from-mime-c88742ee/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.delx.ai](https://www.zero.xyz/host/api.delx.ai/llms.txt)