Text embeddings API: 1,024-dimension vectors (BGE-M3), pay per call

$0.01 per call · failed calls are never charged · no account or subscription: pay per call with a card key or USDC

A 1,024-dimension embedding vector for up to 4,000 characters of text in 100+ languages, from BAAI's BGE-M3. Use for semantic search, RAG retrieval, clustering and deduplication.

When to use it

Semantic search, RAG retrieval, clustering and deduplication
Embed up to 4,000 characters in 100+ languages
Use the same call through the OpenAI-compatible /v1/embeddings

Guide: Text embeddings API

Run it free (25 free calls) Buy credits by card (from $1) Example result (JSON)

Inputs

Name	Type	Description
`text` (required)	string	Text to embed, up to 4,000 characters

Request

Over HTTP, with a card key from /credits:

curl -H "Authorization: Bearer adt_…" "https://tools.funwords.eu/ai/embed?text=pay-per-call%20APIs%20for%20AI%20agents"

Or one of your 25 free calls, no key:

curl "https://tools.funwords.eu/ai/embed?text=pay-per-call%20APIs%20for%20AI%20agents&trial=1"

Without a key, the same URL answers 402 Payment Required with x402 and MPP terms, so an agent with a wallet pays per call in USDC (Base, Polygon, Arbitrum or Solana over x402; Base or Tempo over MPP) and retries.

Example result

{
  "dimensions": 1024,
  "embedding": [
    0.0123,
    -0.0456,
    0.0789
  ],
  "model": "@cf/baai/bge-m3"
}

From an AI agent (MCP)

Add the MCP server to Claude, Cursor or any MCP client. This tool is ai_embed, and the first 25 successful calls are free:

https://tools.funwords.eu/mcp

Questions

Which model and size?

BAAI's BGE-M3, 1,024 dimensions.

Can I send several texts at once?

No, one text (up to 4,000 characters) per call.

How do I pay?

Each successful call costs $0.01; failed calls are not charged. The first 25 calls are free. Then pay with card credits (from $1; the key goes in an Authorization header or, for clients that can only fetch a URL, as api_key= in the URL) or per call in USDC over x402 or MPP. No account is needed.