Dex Data Server

Twenty-three tools for your agent — DEX market data, everyday utilities and reference data. Twenty-two need no API key, no wallet and no signup; one is paid and pays from a wallet you control.

Try it in 30 seconds

claude mcp add dex-data -- npx -y dex-data-mcp

That is the whole install. Ask your agent "what's the price of WBNB on BSC?" and it answers from live on-chain pool state:

{
  "symbol": "WBNB", "priceUsd": 677.25, "network": "bsc",
  "via": "WBNB/USDT", "venues": 7, "totalTvlUsd": 117110555.6,
  "confidence": "HIGH", "spreadBps": 25.26, "blockNumber": 117223818
}

Measured 2026-08-21: all 22 free tools answered keyless, with full payloads. No tool is degraded on the free tier, and none returns a stub or a placeholder — the free answer is the same answer. What the free tier limits is how many calls per day, not what is in them.

Since 1.6.0 there is also one paid tool, get_dex_spread — see Paid tools. It is the only tool that needs a wallet, it is labelled PAID in its own description, and without a wallet it explains what to set and spends nothing. The 22 tools above are unaffected by it.

Twenty-two free tools, no API key and no wallet, in three groups:

• Multi-chain DEX market data — token prices, liquidity depth, pool reserves, best execution venue, liquidity risk, pre-trade slippage and gas costs across BNB Chain, Polygon, Arbitrum, Base, Avalanche and Optimism.
• General-purpose agent utilities — geocoding, reverse geocoding, weather, web search, article/PDF to Markdown, and cryptographic randomness.
• Reference and research data — search autocomplete, public holidays and business days, RSS/Atom feeds, IP geolocation, GLEIF legal-entity lookup and the US Treasury yield curve.

Why this exists

The ledger says it plainly. Of 20,392 paywall challenges recorded, zero were genuine third-party queries — 82.5% were our own monitoring, 17.3% were catalogue crawlers walking every route with no parameters. We were being indexed, not shopped.

Bazaar listings are a bet on demand that does not exist yet. MCP is where agents already are today: Claude Desktop, Claude Code, Cursor, and every other MCP host. This server is the same data, delivered where the users are, and it needs no payment at all for the free tier — which removes the one barrier that a browsing agent cannot cross on its own.

Install

Claude Code

claude mcp add dex-data -- npx -y dex-data-mcp

Claude Desktop / Cursor — add to claude_desktop_config.json:

{
  "mcpServers": {
    "dex-data": {
      "command": "npx",
      "args": ["-y", "dex-data-mcp"]
    }
  }
}

No API key, no wallet, no signup. The free tier answers every tool for a daily allowance; after that the endpoints fall back to x402 micropayments.

Tools

DEX market data

tool	answers
get_token_price	USD price of any ERC-20, by ticker or contract address
get_liquidity	market depth and TVL per venue for a pair
get_best_venue	which DEX is cheapest to buy on / best to sell into
get_slippage	price impact for a specific trade size
get_liquidity_risk	DEEP / MODERATE / SHALLOW / VERY_THIN depth class
get_gas	gas cost in USD per chain, ranked cheapest-first (gwei is not comparable across chains)
get_pool_reserves	raw reserves, fee and TVL per venue at one block — the data the others compute from
find_arbitrage	cross-venue arbitrage now, ranked by gross USD at the optimal size, not raw spread
list_chains	supported chains and indexed tokens

General-purpose agent utilities

Not a change of theme — these were chosen the same way everything else here was. Reading USDC receipts across 1,062 x402 seller wallets on Base ranked what actually gets paid for, and DEX data was not near the top of that list. Forward geocoding was (56 paying wallets), then weather, then article-to-Markdown, then randomness. These are the answers to that data.

tool	answers
geocode	address or place name to coordinates, worldwide (OpenStreetMap)
reverse_geocode	coordinates to the nearest street address
get_weather	current conditions plus up to a 7-day forecast for any coordinates
search	free-text web search to ranked organic results, sponsored rows excluded
url_to_markdown	a public article or PDF URL to clean Markdown
get_random	CSPRNG integers or bytes, for agents that cannot generate their own

Reference and research data

Chosen the same way, but from a corrected reading. The category totals in the original scan were double-counted — the biggest x402 sellers carry 10-16 of the 16 category tags each, so every category reported nearly the whole market's revenue. Seller-level rows are clean, and every tool below is something a wallet took real USDC for during the sampled window.

tool	answers
get_search_suggestions	what people actually type about a topic — autocomplete, expanded into questions and comparisons
get_holidays	public and bank holidays for 100+ countries, and whether a given date is a business day
read_feed	any RSS, Atom or RDF feed as clean JSON, summaries in both HTML and plain text
geolocate_ip	where an IP is, with the datacentre/VPN flag that says whether to believe it
lookup_lei	a company's Legal Entity Identifier by name, with lapsed registrations flagged not hidden
get_treasury_yield_curve	the US par yield curve plus 2s10s / 3m10y / 5s30s and the inversion flag

Local

tool	answers
get_spend_budget	what this session has spent on paid calls, and the caps in force

Paid — needs a wallet you control

tool	answers	price
get_dex_spread	real-time cross-DEX price & spread on BSC: per-venue prices across PancakeSwap v2, PancakeSwap v3 (all fee tiers), Biswap and ApeSwap in one call, plus best buy/sell venue, gross arbitrage spread (bps + USD), optimal trade size, liquidity and block number	$0.01 USDC/call, no free tier

This tool used to be a separate package, bsc-dex-spread-mcp. It lives here now: one install, one config, free tools and paid tools side by side. Nothing else changed — same route, same data, same price.

Before you reach for it, the free tools may already answer you. get_liquidity gives per-venue depth for a pair and find_arbitrage gives a cross-venue spread scan, both inside the 25-calls-a-day free tier with no wallet at all. get_dex_spread is worth paying for when you want all four BSC venues and the optimal trade size in a single call, or when you have exhausted the free allowance.

Pairings worth knowing: geocode then get_weather turns a place name into a forecast, search then url_to_markdown turns a question into readable source text, and read_feed then url_to_markdown turns a feed into full articles.

Free tier

Every one of the 22 free tools answers within a daily per-caller allowance — no wallet, no signup. The remaining quota is returned on X-FreeTier-Remaining. Beyond it, calls fall back to x402 micropayments (USDC on Base). get_dex_spread is the exception: it is paid from the first call and has no allowance.

Every response carries the liquidity backing the number and a confidence rating. A quote with no depth behind it is refused rather than returned — a dust-pool price is worse than no price when an agent may trade on it.

Paying: the wallet is yours, and this package ships no keys

This package contains no private key, no seed and no funded wallet. Payment is opt-in and off unless you set a key yourself; a package strangers install must never move funds because a model called a tool a few extra times.

Set one of these in your MCP client's env block for this server:

{
  "mcpServers": {
    "dex-data": {
      "command": "npx",
      "args": ["-y", "dex-data-mcp"],
      "env": { "DEX_WALLET_KEY": "0x<64 hex chars>" }
    }
  }
}

EVM_PRIVATE_KEY is accepted as an alias — it is the name the CDP x402 docs use and the name bsc-dex-spread-mcp read, so an existing config for that package keeps working unchanged.

• Fund it with USDC on Base and nothing else. x402's exact scheme is EIP-3009: you sign an off-chain authorization and the facilitator broadcasts and pays the gas, so the wallet needs zero ETH.
• Use a burner. The key sits in your MCP client config in plaintext. A few dollars of USDC, never a main wallet.
• Spend is capped and fails closed — DEX_MAX_SPEND_USD (default $1 total for the process), DEX_MAX_PRICE_USD (default $0.05 for any single call) and DEX_MAX_CALLS (default 200). Hitting any one stops payment and returns a plain explanation rather than continuing to spend. The asking price is read from the 402 challenge and refused before paying if it exceeds the ceiling.
• get_spend_budget reports what this session has spent and the caps in force.

Without a wallet, get_dex_spread returns the price, the two env var names, the shape of the value and the free alternatives — never a stack trace, and never a silent failure.

Honest limits

• Depth and prices cover the venues this API indexes; a deeper pool may exist on a DEX not covered here.
• v3 figures distinguish custody TVL from tradeable depth at the current price. They are not the same number and are not labelled as if they were.
• get_slippage is pool-level price impact: it excludes gas, MEV and multi-hop routing, and flags v3 estimates that cross the active tick band.
• A tool called without its required argument is refused before any request is made, so a malformed call never spends a free-tier slot or a cent. The refusal names the argument: search needs q, get_slippage needs amountUsd or amountIn, lookup_lei needs q or lei.

Where to go next

• Cross-DEX spread only, on six chains — arb-dex-mcp is the focused sibling: npx -y arb-dex-mcp. Keyless too, and its free answers carry a limitation field naming exactly what a key would add.
• Paid, per-call BSC spread — that is now the get_dex_spread tool in this package; you do not need a second install. It was previously the standalone bsc-dex-spread-mcp, which still works and is unchanged, but this server is where it is maintained.
• You want the compliance pair (OFAC screening, GLEIF LEI) — agent-utils-mcp.
• You want the human-approval job queue this whole stack is operated by — approval-queue-starter, one file, zero dependencies.
• The weekly measurements, free — https://arbdatadesk.beehiiv.com. The live dashboard — https://arb-dex-data-production.up.railway.app/dashboard.