BlockRun MCP

Real-time data for Claude — markets, research, X/Twitter, crypto. No API keys. Pay per call.

claude mcp add blockrun -s user -- npx -y @blockrun/mcp@latest

Wallet auto-created. Fund with $5 USDC. Ask Claude anything.

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What changes

Before BlockRun, Claude can't answer:

• "What's the current Polymarket probability that Bitcoin hits $100k this year?"
• "Find me the top 5 papers on RAG published in the last 30 days"
• "What are people saying about @sama on X right now?"
• "What's the 24h volume on the PEPE/ETH pair on Uniswap?"

After BlockRun, it can. Each query costs fractions of a cent, billed from a local USDC wallet. No subscriptions. No API dashboards. No key rotation.

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Demo

User: What's Polymarket saying about the Fed rate decision next month?

Claude: According to Polymarket, the market currently puts a 73% probability on the Fed holding rates steady at the May meeting, with 24% on a 25bp cut and 3% on a hike. Volume over the last 24h: $2.1M. The "Hold" contract last traded at $0.73.

(via blockrun_markets · cost: $0.001)

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User: Find recent papers on speculative decoding and summarize the key approaches

Claude: I found 8 papers from the last 60 days via neural search. The dominant approaches are: (1) draft model selection — smaller models predicting N tokens ahead for the larger model to verify in parallel...

(via blockrun_exa · cost: $0.01)

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Showcase

Posters generated through blockrun_image with openai/gpt-image-2. Each is a single API call routed through BlockRun, paid in USDC on Base.

Latest — GPT-5.5 now live on BlockRun

Gallery

Cornell Blockchain Conference 2026 — packed booth recap	Cornell Blockchain Conference 2026 — quiet variant	100 Trillion Tokens — milestone synthwave poster

Prompts and a worked example for these are in skills/image-prompting/SKILL.md.

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Prerequisites

• Node.js ≥ 18 (node -v)
• ~$5 USDC on Base or Solana (the server auto-creates a wallet on first run; see Fund your wallet)
• An MCP client: Claude Code, Claude Desktop, Cursor, Windsurf, or ChatGPT Desktop

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Install

Claude Code (recommended)

claude mcp add blockrun -s user -- npx -y @blockrun/mcp@latest

The -s user flag installs globally (available in every project). The -- separator ensures -y is passed to npx, not parsed by claude mcp add.

Claude Desktop — add to claude_desktop_config.json:

{
  "mcpServers": {
    "blockrun": {
      "command": "npx",
      "args": ["-y", "@blockrun/mcp"]
    }
  }
}

Hosted (no install, always latest)

claude mcp add blockrun -s user --transport http https://mcp.blockrun.ai/mcp

Cursor — add to ~/.cursor/mcp.json (macOS / Linux) or %APPDATA%\Cursor\mcp.json (Windows):

{
  "mcpServers": {
    "blockrun": {
      "command": "npx",
      "args": ["-y", "@blockrun/mcp@latest"]
    }
  }
}

Windsurf — same JSON, in:

• macOS: ~/.codeium/windsurf/mcp_config.json
• Linux: ~/.config/.codeium/windsurf/mcp_config.json
• Windows: %APPDATA%\Codeium\windsurf\mcp_config.json

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Fund your wallet

Run blockrun_wallet to see your address. Send USDC on Base.

Method	Steps
Coinbase	Send → USDC → Base network → paste address
Bridge from Ethereum	bridge.base.org

$5 covers ~5,000 market queries, ~500 Exa searches, ~250 image generations, or ~30 Seedance 1.5-pro clips (5s).

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Tools

Tool	Data source	Cost
blockrun_chat	55+ LLMs (GPT, Claude, Gemini, DeepSeek, Kimi K2.6, GLM, NVIDIA free tier, ...) with mode tier routing	per token
blockrun_image	DALL-E 3, GPT Image 1/2, Grok Imagine, Flux, CogView-4, Nano Banana — generation + editing	$0.015–0.12
blockrun_video	xAI Grok Imagine Video + ByteDance Seedance 1.5/2.0/2.0-fast	$0.03–0.30/sec
blockrun_music	MiniMax music generation	per track
blockrun_price	Pyth-backed realtime + OHLC — crypto / FX / commodity (free), 12 stock markets (paid)	free or $0.001/call
blockrun_markets	Polymarket (markets, candles, trades, orderbooks, leaderboards, smart-wallet PnL/clusters, UMA oracle), Kalshi, Limitless, Opinion, Predict.Fun, dFlow, Binance Futures, cross-platform match + search	$0.001–0.005/query
blockrun_surf	Surf (asksurf.ai) — 84 endpoints: CEX market data, on-chain SQL (13 chains, 80+ ClickHouse tables), 100M+ labeled wallets, Polymarket + Kalshi side-by-side, social mindshare, news, search, Surf-1.5 chat with citations	$0.001–0.02/call
blockrun_exa	Neural web search (Exa) — research, competitors, papers, URL content	$0.01/query
blockrun_search	Grok Live Search — web + news with citations	~$0.025 per source
blockrun_dex	Live DEX prices via DexScreener	free
blockrun_models	Live catalogue of every LLM/image/video/music model + pricing	free
blockrun_wallet	Balance, spending, agent budgets, setup QR	free

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Tips for effective LLMs

For LLMs and agents invoking BlockRun MCP tools:

• CRITICAL: When any blockrun_* tool returns a payment / balance / 402 error, call blockrun_wallet first to check status, then action:"setup" to get funding instructions. Don't retry the failing tool blindly — the wallet is empty.
• CRITICAL: For blockrun_markets and blockrun_surf, the 80+ endpoint catalog lives in skills/markets/SKILL.md and skills/surf/SKILL.md, NOT in the tool description. Browse the skill before guessing endpoint paths.
• CRITICAL: blockrun_chat routing:"smart" (ClawRouter) only works on Base wallets. On Solana, pass mode: or model: to pick a model directly.
• CRITICAL: blockrun_music and blockrun_video are payment-on-completion async. Failures or client-side timeouts do NOT charge. Don't retry-loop them — they may take 60–180s.
• CRITICAL: Before spawning child agents, allocate per-agent budget: blockrun_wallet action:"delegate" agent_id:"X" agent_limit:1.00. Pass agent_id:"X" to every downstream blockrun_* call — the child is auto-blocked when the budget hits zero.
• Free tier first for drafts: blockrun_chat mode:"free" (NVIDIA), blockrun_dex, blockrun_price (crypto / FX / commodity), and blockrun_models are all $0. Use them to scaffold before paying for premium models.

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Key Use Cases

What kinds of questions can Claude (or any LLM agent) answer once BlockRun MCP is installed:

1. Price reads / market data

   "What's BTC trading at? Compare with last week's average." → blockrun_price (free) or blockrun_surf path:market/price

2. Prediction-market consensus

   "What's Polymarket's odds for the next Fed rate decision?" → blockrun_markets path:polymarket/events + filter

3. On-chain forensics

   "This wallet (0xabc...) — what's it labeled as? What does it hold? When did it whale up?" → blockrun_surf paths:wallet/labels/batch, wallet/detail, wallet/net-worth

4. Cited research with sources

   "Find the 5 most-cited papers on speculative decoding from the last 90 days. Summarize the dominant approach." → blockrun_exa action:search then contents

5. Image generation with on-image text

   "Generate a poster announcing GPT-5.5 on BlockRun, retro-futuristic, with the headline 'NOW LIVE'." → blockrun_image + the image-prompting skill 5-section framework

6. Voice phone-out

   "Call +1-415-555-... and confirm the appointment on Friday at 3pm." → blockrun_phone path:voice/call, body: { to, task, from } (provision from first via phone/numbers/buy), then poll voice/call/{call_id}

7. Multi-agent research with budget cap

   "Spawn 3 research agents on competing L1 narratives. Cap each at $0.50." → blockrun_wallet delegate × 3 → children call blockrun_chat + blockrun_exa with their agent_id

8. Cross-chain SQL forensics

   "Top 10 tokens by DEX volume on Base in the last 24h." → blockrun_surf path:onchain/sql, body: { sql: "SELECT..." }

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Why not just use the APIs directly?

	Direct APIs	BlockRun
Exa	Sign up, $20/mo minimum	$0.01/call, no subscription
Polymarket	Undocumented, rate-limited	$0.001/call, clean JSON
Surf (asksurf.ai)	Account + monthly plan	$0.001/call, no Surf account, 84 endpoints
Multiple sources	3 accounts, 3 API keys, 3 billing pages	1 wallet

One wallet. All sources. No dashboards.

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When NOT to use BlockRun MCP

BlockRun shines when you want unified billing + many sources + LLM-readable errors. It is not the right fit for:

• High-volume single-API workloads (≥10k calls/day to one source). Direct subscriptions amortize better past the break-even point — Polymarket's free public API plus your own caching beats $0.001 × 10k/day if you don't need cross-source aggregation.
• Compliance-sensitive flows that need a fiat invoice / audit trail. BlockRun settles in USDC; receipts are on-chain (Basescan / Solscan) but are not tax invoices. For enterprise procurement, contract directly with the upstream provider.
• Latency-critical sub-100ms reads. Each x402 call adds ~200–500ms of payment-signing + settlement overhead vs. a direct authenticated request. For HFT-style flows, run your own infra.
• You only need one source forever. If you'll only ever call Polymarket, or only ever Exa, save the indirection — sign up upstream and skip the wallet.

Use BlockRun when you want pay-per-call for exploration, aggregation, or agent-driven workloads where you can't predict which source you'll reach for next.

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Multi-agent budget delegation

Delegate a spending budget to a child agent with agent_id. The child is auto-blocked when the budget runs out — useful for autonomous agents that shouldn't run up unbounded costs.

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Troubleshooting

• Insufficient balance / HTTP 402 after retry → Run blockrun_wallet action:"setup". Send USDC on Base (or Solana — see Environment Variables).
• Smart routing (ClawRouter) is not available on Solana → Pass model: or mode: explicitly to blockrun_chat, or switch back to Base by unsetting SOLANA_WALLET_KEY and removing ~/.blockrun/.solana-session.
• claude mcp list doesn't show blockrun → Check node -v (must be ≥18). Clear the npx cache: rm -rf ~/.npm/_npx. Re-run the install command from above.
• fetch failed / timeout when checking wallet balance → Base RPC transient outage. The tool already falls through 3 public RPCs; retry after 30s. Persistent failures usually = local proxy / firewall blocking outbound RPC.
• ENOENT: ~/.blockrun/.session → Expected on first run. The server auto-creates the wallet; check stderr for the WALLET_CREATED line confirming the address.
• Video generation timed out (5-min cap) → Upstream Seedance / xAI queue congestion. No charge (payment-on-completion). Retry, or pick a faster model (bytedance/seedance-1.5-pro).
• Music generation timed out (200s cap) → Same pattern. No charge. Retry; if it persists, the upstream model is rate-limited — try off-peak.

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Environment Variables

Variable / File	Default	Effect
~/.blockrun/.session	auto-created on first run	EVM private key (0x...). File exists → use Base.
~/.blockrun/.solana-session	not created	Solana private key. File exists → switch to Solana.
SOLANA_WALLET_KEY	unset	Env-var override of .solana-session. Set → use Solana.

Chain selection priority (see src/utils/wallet.ts:24):

1. SOLANA_WALLET_KEY env var present → Solana
2. ~/.blockrun/.solana-session exists → Solana
3. Otherwise → Base (~/.blockrun/.session auto-created)

Switching chains:

• Base → Solana: export SOLANA_WALLET_KEY=..., or echo "<secret>" > ~/.blockrun/.solana-session
• Solana → Base: unset SOLANA_WALLET_KEY && rm ~/.blockrun/.solana-session (the existing .session is reused, so it's the same Base wallet)

The server also runs a non-blocking npm registry check at startup and prints an Update available notice to stderr when a newer @blockrun/mcp version exists. Upgrade by re-running the install command — no manual npm update needed.

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How it works

Pay-per-call via x402 micropayments in USDC. Your wallet lives at ~/.blockrun/.session (Base) or ~/.blockrun/.solana-session (Solana). The private key never leaves your machine.

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Contributing

PRs welcome. See CONTRIBUTING.md for setup, the tool-vs-skill design rule, and how to add a new partner API.

Issues: github.com/blockrunai/blockrun-mcp/issues

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blockrun.ai · npm · @BlockRunAI