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AI Chat

How to Chat with AI Using Bitcoin Lightning

Top-tier models. No account. No subscription. Pay per message with a Lightning wallet.

From 1 sat/messageNo account requiredMultiple modelsL402 / MCP / OpenClaw

For Humans

Use the web UI — no setup required.

Every AI chat service wants your email, your credit card, and a monthly commitment before you can send a single message. Sats4AI skips all of that. Type a message, pay a Lightning invoice, get an answer. Works from any browser. Nothing stored, nothing tied to your identity.

Quick research without a subscription

Need a top-tier model for one task? Send a few messages, pay a few sats, walk away. No plan to cancel, no trial period to remember.

Private conversations by default

No account means no conversation history linked to you. Useful for sensitive topics, competitive research, or simply not wanting to feed a training dataset.

Coding help with the best models

Free tiers give you weak models with rate limits. Sats4AI gives you access to models built for deep reasoning and code — at pennies per message, not $20/month.

Images and files too

Attach a screenshot, a PDF, or an image to your message. Ask the model to explain, summarize, or act on it — all included in the same pay-per-message flow.

Available Models

BESTFlagship Model

Kimi K2.5

100 chars/sat
no minimum
1T
Parameters
262K
Context
Yes
Vision
Yes
Files

Rivals the best proprietary models. Advanced reasoning, thinking mode, code generation, image understanding, and file analysis. Ideal for complex tasks that demand intelligence.

FASTSpeed Optimized

GPT-OSS

333 chars/sat
no minimum
117B
Parameters
131K
Context
Ultra
Speed
Yes
Reasoning

117B open-weight reasoning model with ultra-fast inference. No cold starts, instant responses. Perfect for quick answers, code generation, writing, and everyday tasks where speed matters.

For Agents

Integrate via L402, MCP, or OpenClaw — no account, no API key.

The text generation endpoint supports L402 authentication: your agent or script pays per message with a Lightning micropayment. No API key to manage, no billing account to set up, no monthly minimum. The model processes the message and returns a streamed response — same models, same quality, fully automated.

PIPELINE

Automated content pipelines

A script fetches a topic, calls the text generation API to draft it, then passes the output to TTS or email delivery — each step paid independently via Lightning.

CODING

AI coding assistant for your agent

Power an OpenClaw or MCP-connected coding agent with Kimi K2.5 — 1T parameter reasoning for code review, debugging, and generation at a fraction of subscription costs.

ANALYSIS

Document and data analysis

An agent uploads a PDF or CSV and asks the model to extract, summarize, or classify the contents. File support included in every message — no extra setup.

CHAIN

Multi-step reasoning chains

Chain multiple calls: analyze an image with Vision, feed the description to text generation for a report, then send the report by email — all in one automated workflow.

L402 Authentication Flow

1

Send the request without auth

POST your message and model choice to the endpoint. The server responds with HTTP 402 + a Lightning invoice in the WWW-Authenticate header.

2

Pay the Lightning invoice

Your agent pays the invoice using a Lightning wallet or library. Save the preimage from the payment result.

3

Resend with the preimage

Repeat the identical request, adding an Authorization: L402 <macaroon>:<preimage> header. The server validates and returns the AI response.

terminal
# One command — lnget handles invoice, payment, and retry automatically
lnget -X POST https://sats4ai.com/api/l402/generate-text \
  --json '{"input":[{"role":"User","content":"Explain Bitcoin in one sentence"}]}'
COST

How Much Does It Actually Cost?

Sats4AI charges per message based on token length. Compare that to flat monthly subscriptions:

UsagePremium AI SubscriptionsSats4AI (Kimi K2.5)
Light (100 msgs/mo)$20/mo minimum~1,500 sats (~$0.60)
Medium (500 msgs/mo)$20–100/mo~7,500 sats (~$3)
Heavy (2,000 msgs/mo)$100–200/mo~30,000 sats (~$12)
Signup requiredAccount + email + credit cardNone

Bottom line: 500 messages/month to a top-tier model costs ~$3 on Sats4AI vs. $20–200 on premium subscriptions. That's up to 60x cheaper, and you never pay for a month you don't use. Prices scale with message length; web search adds +2 sats.

Chain with Other Services

AI ChatText-to-Speech
AI ChatImage Generation
VisionAI Chat
AI ChatSMS

Try It Now — No Signup Required

Top-tier AI from 1 sat per message. All you need is a Lightning wallet.