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The bf-create-market Claude Code skill is the simplest way to launch BlockForecast markets from an AI agent. Install once, run a slash command, the skill handles the rest: derives your wallet from a private key, checks creator approval, signs the $1 USDC payment via x402 on Base, posts the market, and returns the URL. Creator-fee earnings (0.5% of every trade) flow back to your wallet automatically. If you’re not using Claude Code, see the manual x402 Quickstart — same endpoint, you write the glue code.

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Install

In a Claude Code session: 
/plugin marketplace add gr8estman/blockforecast-skills
/plugin install bf-create-market@gr8estman
The skill is open source — source on GitHub: gr8estman/blockforecast-skills.

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One-time setup

1

Get an EVM wallet

Any tooling — viem, MetaMask, Coinbase, hardware wallet. The skill needs the private key of the wallet your agent will create markets from.
import { generatePrivateKey, privateKeyToAccount } from 'viem/accounts';
const key = generatePrivateKey();
console.log('address:', privateKeyToAccount(key).address);
console.log('key:    ', key);
Save the key in your secrets manager (1Password, Doppler, AWS Secrets Manager, env file in your secrets store) — this is plain-text private-key custody, treat it accordingly.
2

Fund with USDC on Base

Send ~5USDC(Basemainnet)totheagentaddress.BridgefromEthereummainnetviathe[officialBasebridge](https://bridge.base.org),oroff−rampdirectlyfromCoinbasetoBase.Eachmarketcreationcosts∗∗5 USDC (Base mainnet) to the agent address. Bridge from Ethereum mainnet via the [official Base bridge](https://bridge.base.org), or off-ramp directly from Coinbase to Base. Each market creation costs **1 USDC** plus a few cents of gas.
3

Apply for creator access

Visit blockforecast.io/apply and sign in with the same wallet (use “Connect wallet” → External wallet). Submit the application. Approval typically lands in under 24 hours; you’ll be notified via X DM on the handle you submitted.
The skill will not call the paid endpoint until your wallet shows status: approved. The $1 x402 fee is non-refundable on unapproved wallets, so apply first.
4

Set the env var

export BF_AGENT_KEY="0x<your-64-char-hex-key>"
Add it to your shell rc, your secrets store, or whatever launches your Claude Code session.

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Usage

/bf-create-market "Will the Fed cut rates in May 2026?" 2026-05-31
The skill will:
  1. Check BF_AGENT_KEY is set
  2. Verify the wallet is approved
  3. Show you a confirmation summary
  4. Wait for your “yes” before spending USDC
  5. POST to BlockForecast with x402 payment
  6. Return the live market URL

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Dry run

To verify your setup without spending USDC: 
DRY_RUN=1 /bf-create-market "Will X happen by Y?" 2026-12-31
The skill runs all preflight checks and prints what it would send, then exits.

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Inputs

ArgumentRequiredFormatNotes
questionyesstring ≥10 charsBinary, ends with ?
resolveDateyesYYYY-MM-DDMust be in the future
categorynoone of crypto, politics, sports, culture, science, world, ai, esportsDefault: crypto
Behind the scenes the skill POSTs to /api/v2/x402/markets — the Create Market via x402 page documents the underlying payload and response.

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Costs

ActionCost
Apply for creator accessFree
Create one market via the skill1USDC+ 1 USDC + ~0.001 gas
Earn from trades on your market0.5% of every trade — paid to your wallet in real time
Withdraw earningsGas only
A market doing 50koflifetimevolumenetsthecreator50k of lifetime volume nets the creator 250. Most active creators run a portfolio of 30+ markets.

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Errors and what to do

Skill errorMeaning
missing_keyRun export BF_AGENT_KEY="0x..."
bad_keyKey must be 32 bytes hex with optional 0x prefix
creator_not_approvedOne-time apply at /apply
creator_pendingWait for approval (~24h) — you’ll be DM’d on X when it lands
creator_rejectedSee rejection reason; address it; reapply at /apply
creator_suspendedContact support@blockforecast.io
insufficient_usdcAdd USDC on Base to the agent wallet
payment_failedCoinbase CDP facilitator hiccup — retry in a minute

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Security notes

  • The skill only signs the exact x402 payment payload for POST /api/v2/x402/markets. It does not trade, withdraw, or move funds.
  • Creator-fee earnings flow to the wallet derived from BF_AGENT_KEY. Keep that key tightly scoped — anyone with it can also withdraw your earnings.
  • The skill prompts for explicit confirmation before every paid call. There is no auto-execute mode.
  • Treat BF_AGENT_KEY like a production secret: rotate periodically, never commit, never paste in chat.

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Roadmap

These skills are planned next — they share the same wallet + creator setup:
  • bf-resolve-oracle — query oracle consensus on any yes/no question ($0.05 USDC per call)
  • bf-check-balance — read agent wallet’s USDC balance + open positions
  • bf-list-markets — search BlockForecast markets by category
  • bf-trade — place a trade on an existing market

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Source + support