Signet

Signet is an onchain advertising protocol on Base (Hunt Town Co-op). URLs compete for the spotlight slot, backed by HUNT tokens.

CLI Tool

Install and use the @signet-base/cli tool:

# Estimate cost for spotlight placement in different tokens
npx @signet-base/cli estimate --hours 6 --token hunt
npx @signet-base/cli estimate --hours 6 --token eth

# List recent signatures
npx @signet-base/cli list --count 10

# Sign directly on-chain (recommended if you have ETH or USDC)
npx @signet-base/cli sign --url https://example.com --hours 6 --token auto --private-key 0x...

# Post via x402 payment protocol
npx @signet-base/cli post --url https://example.com --hours 6 --simulate
PRIVATE_KEY=0x... npx @signet-base/cli post --url https://example.com --hours 6

Commands

estimate — Get estimated cost in various tokens. Options: --hours <0-24>, --token <eth|usdc|mt|hunt>
sign — Sign directly on-chain with smart token selection. Options: --url <url>, --hours <1-24>, --token <eth|usdc|mt|hunt|auto>, --private-key <key>, --slippage <percent>
list — List recent spotlight signatures. Options: --count <n>
post — Place a URL on the spotlight via x402 payment. Options: --url <url>, --hours <0-24>, --private-key <key>, --simulate

Smart Token Selection

The sign command supports automatic token selection with --token auto:

Checks balances of HUNT, USDC, ETH, MT (in priority order)
For each token, estimates the required amount including slippage
Selects the first token where balance >= required amount
Automatically handles approvals for ERC20 tokens

Recommendation: If you have ETH or USDC, use signet sign for direct on-chain posting — it's more reliable than the x402 flow.

The --simulate flag on post runs the full x402 flow (estimate, get 402 requirements, create payment) but stops before submitting. Use it to verify costs before committing.

API (Direct HTTP)

Base URL: https://signet.sebayaki.com

Estimate Cost

curl "https://signet.sebayaki.com/api/x402/estimate?guaranteeHours=0"

Response:

{
  "guaranteeHours": 0,
  "estimatedUSDC": "12.28",
  "estimatedUSDCRaw": "12280000",
  "spotlightAvailable": true,
  "spotlightRemainingSeconds": 0
}

guaranteeHours (0-24): hours the spotlight is guaranteed. 0 = can be overtaken immediately.

List Signatures

curl "https://signet.sebayaki.com/api/signature/list?startIndex=0&endIndex=5"

Returns { signatures: [{ signatureIndex, url, huntAmount, viewCount, clickCount, metadata, timestamp, userWallet }] }.

Post Spotlight (x402)

# Step 1: POST without payment → 402 with requirements
curl -X POST https://signet.sebayaki.com/api/x402/spotlight \
  -H "Content-Type: application/json" \
  -d '{"url":"https://example.com","guaranteeHours":0}'

# Step 2: POST with payment header → 200
curl -X POST https://signet.sebayaki.com/api/x402/spotlight \
  -H "Content-Type: application/json" \
  -H "X-402: <encoded-payment>" \
  -d '{"url":"https://example.com","guaranteeHours":0}'

The x402 payment flow:

Server returns 402 with accepts array (USDC amount, payTo address, network)
Client signs a USDC payment (Permit2 on Base) using @x402/core and @x402/evm
Client retries with payment header
Server verifies via facilitator, executes onchain tx, settles payment

Guidance for AI Agents

If you have ETH or USDC, you can post to Signet directly using signet sign — this is often more reliable and gives you better control over gas fees and slippage than the x402 flow.

Use the MCP tools:

signet_estimate — Check cost in different tokens before posting
signet_sign — Post directly on-chain (recommended for ETH/USDC holders)
signet_post — Post via x402 (fallback option)
signet_list — View recent ads and their performance