ephemeral-cloud-mcp

MCP server for Ephemeral Cloud: disposable infrastructure for AI agents, paid per use with x402 (USDC on Base). No accounts, no API keys, no subscriptions.

It gives any MCP client (Claude Code, Claude Desktop, Cursor, …) three capabilities most agents lack:

| Tool | What it does | Price | |---|---|---| | create_watch | We poll a public URL until a mechanical condition holds (text appears / disappears, JSON path equals, content or status changes) and hold the result for you. Outsource the waiting instead of burning LLM wake-ups. | $0.25 up to 24h · $1.00 up to 7 days | | create_webhook | A temporary inbound webhook URL you can hand to any third party. Incoming requests are stored until you collect them. | $0.01 (≤1h) · $0.05 (≤24h) · first one per IP free | | create_callback | A delayed wake-up: after delay_seconds your payload lands in a mailbox (and is POSTed to a callback_url that proves ownership). | $0.01 |

Plus get_events (collect results), delete_resource (end early) and service_info (the live machine-readable spec). Every resource auto-expires.

Install

Claude Code:

claude mcp add ephemeral-cloud -- npx -y ephemeral-cloud-mcp

Claude Desktop / Cursor / any MCP client (mcpServers config):

{
  "mcpServers": {
    "ephemeral-cloud": {
      "command": "npx",
      "args": ["-y", "ephemeral-cloud-mcp"]
    }
  }
}

Without a wallet, the server works on the free tier and returns the exact 402 price quote for anything paid, so the agent always knows what something costs.

Let the agent pay

Give the server a wallet that holds a little USDC on Base (mainnet). Its balance is the spending cap; use a dedicated wallet with a few dollars in it, never your main one.

claude mcp add ephemeral-cloud -e WALLET_KEY_FILE=$HOME/.config/ephemeral-cloud/agent-wallet.key -- npx -y ephemeral-cloud-mcp

| Variable | Meaning | |---|---| | WALLET_KEY_FILE | Path to a file containing the wallet's private key (0x…). Preferred: keeps the key out of config files. | | WALLET_PRIVATE_KEY | The key itself, if you'd rather pass it directly. | | EPHEMERAL_CLOUD_URL | Point at a different deployment (defaults to the hosted service). |

Payments use the x402 v2 protocol: the service answers 402 Payment Required with an exact USDC quote, the server signs a transfer authorization, and the Coinbase CDP facilitator settles it on Base. Gas is sponsored; you only need USDC.

Example

Watch https://example.com/product until the text "In stock" appears, checking every 5 minutes for up to a day, then tell me.

The agent calls create_watch once ($0.25), and later get_events with the returned read_token to collect the matched result. Compare with polling every 5 minutes from the agent itself: 288 wake-ups.

Safety

Delivery is pull-first. Push (callback_url) only goes to URLs that echo a challenge nonce, so the service can't be used to hit arbitrary endpoints. Watches respect robots.txt, block private/metadata IP ranges, cap redirects and response sizes, and run no code. Payloads are small and TTLs are short by design.

Machine-readable spec

GET https://kat3jr5vny647y4sobq6ot2mvq0ewqjt.lambda-url.us-east-1.on.aws/.well-known/x402

License

MIT

What's new in 0.2.0

create_watch gained three arguments:

• email - a person's address to notify when the watch fires. Fixed-template email with a one-click block link; no confirmation step.
• condition_type: "json_any" with json_where - fires when any item in the JSON list at json_path passes every field test, e.g. a Shopify variants list where available is true, title contains "256GB" and price is under 105000.
• mode: "repeat" - keep watching after a match; fires again once the condition clears and holds again. Combined with expires_in_seconds up to 30 days ($3.00) this is a restock alert an agent can set up in one call.