Name: Blockscout
Author: blockscout

LABSCO SUMMARY

Chain data arrives already decoded: calls separated from token transfers, transaction input parsed, balances carrying their token metadata.

The tools are shaped around what fits in a context window rather than around API parity — get_block_info omits the block's transaction hashes unless you ask, get_transaction_info drops raw input when a decoded version exists, and both address history tools page with a cursor. Two rules shape a session: __unlock_blockchain_analysis__ has to be called exactly once before anything else in a session, and lookup_token_by_symbol returns only the first 7 matches, so a widely reused symbol may still need the address from somewhere else.

What it is

A server over Blockscout's multichain API, 16 tools spanning blocks, addresses, tokens, NFTs, transactions and verified contract code, with the chain selected per call by chain_id.

What you get

Address history split the way the API splits it: get_transactions_by_address returns native transfers and contract calls and deliberately excludes token transfers, get_token_transfers_by_address returns the ERC-20 side, both with age_from and age_to windows and cursor pagination
Holdings and collectibles: get_tokens_by_address returns ERC-20 balances with contract details, exchange rate, market cap and holder counts, and nft_tokens_by_address groups ERC-721, ERC-404 and ERC-1155 instances by collection with their metadata attributes
Contract inspection in three levels — get_contract_abi for the interface, inspect_contract_code for verified source or metadata, read_contract to call a view function or simulate a state-changing one through eth_call and get the decoded result
Transactions and blocks arriving decoded: get_transaction_info returns decoded input parameters, token transfers with metadata and a fee breakdown including priority and burnt fees, while get_block_info reports gas used, burnt fees and transaction count
Lookups that turn a name into an address: get_address_by_ens_name for ENS, lookup_token_by_symbol for a symbol or name, get_block_number for the block at a given datetime, get_chains_list to resolve a chain name to its chain_id
direct_api_call for chain-specific endpoints with no dedicated tool, using the same cursor and chain conventions as the rest

Requirements

A chain_id on every call — get_chains_list resolves one from a chain name, and Ethereum Mainnet is 1 — and one call to __unlock_blockchain_analysis__ at the start of a session, before any other tool, which is what the session_id argument on the rest refers back to. A Blockscout PRO API key (keys start with proapi_), sent as the Blockscout-MCP-Pro-Api-Key header to the hosted endpoint, or set as BLOCKSCOUT_PRO_API_KEY when you run the server yourself.

Setup effort

One command plus a key — claude mcp add --transport http blockscout https://mcp.blockscout.com/mcp --header "Blockscout-MCP-Pro-Api-Key: proapi_your_key_here", then supply credentials

See installation options

USE CASES

01

Working out what a wallet actually holds

Read the address itself for balance, age and whether it is a contract, then the ERC-20 holdings with their market data, then the NFTs grouped by collection.

get_address_infoget_tokens_by_addressnft_tokens_by_address

02

Tracing where a transfer ended up

Open the transaction with its input decoded and fees broken down, then follow the address's token movements in a time window — remembering that the native-transfer tool leaves token transfers out on purpose.

get_transaction_infoget_token_transfers_by_addressget_transactions_by_address

03

Reading a contract you did not write

Pull the ABI to see what it exposes, open the verified source or a single source file, then call a view function and get the decoded result rather than raw bytes.

get_contract_abiinspect_contract_coderead_contract

04

Pinning an event to a point in time

Resolve the chain by name first, find the block that was current at a given timestamp, and read that block's gas, fees and transaction count before pulling the transaction list.

get_chains_listget_block_numberget_block_info

05

Starting from a name instead of an address

Turn an ENS domain into an address, or a token symbol into candidate contracts, before any of the address tools can be used — the symbol lookup returns matches by similarity, so pick carefully.

get_address_by_ens_namelookup_token_by_symbol

16 tools

Counted once with only startup setup. Other versions, modes or optional credentials may expose a different list.

`__unlock_blockchain_analysis__`

Initializes a Blockscout MCP session: returns server reference data, the blockscout-analysis skill pointer, and the URI resolution rule. Call this tool exactly once per session, before any other tool, and reuse its payload for the rest of the session; do not call it again.

BEFORE YOU INSTALL

What to know first

Tools you get

16 tools when we connected.

Requires

A client that can reach a remote MCP server over HTTP
A Blockscout PRO API key (prefixed proapi_, free tier at dev.blockscout.com): the hosted setups send it in the Blockscout-MCP-Pro-Api-Key header; a server you run yourself reads it from BLOCKSCOUT_PRO_API_KEY

CONTEXT COST

Moderate Standing cost

Rated by the size of the 16 tool definitions that ride along on every turn, not by how many there are

INSTALLATION

Connect your client

Server setup

claude mcp add

Claude Code

TERMINAL

claude mcp add --transport http blockscout https://mcp.blockscout.com/mcp \
  --header "Blockscout-MCP-Pro-Api-Key: <YOUR_BLOCKSCOUT_MCP_PRO_API_KEY>"

Hosted endpoint

ENDPOINT URL

https://mcp.blockscout.com/mcp

Add this hosted endpoint to your MCP client using the credentials listed under Requirements.

MCP Clients

Claude Desktop — Docker proxy

CLAUDE DESKTOP — DOCKER PROXY · JSON

{
  "mcpServers": {
    "blockscout": {
      "command": "docker",
      "args": [
        "run",
        "--rm",
        "-i",
        "sparfenyuk/mcp-proxy:latest",
        "--transport",
        "streamablehttp",
        "--headers",
        "Blockscout-MCP-Pro-Api-Key",
        "<YOUR_BLOCKSCOUT_MCP_PRO_API_KEY>",
        "--headers",
        "Blockscout-MCP-Intermediary",
        "ClaudeDesktop",
        "https://mcp.blockscout.com/mcp"
      ]
    }
  }
}

Codex

CODEX · TOML

[features]
experimental_use_rmcp_client = true

[mcp_servers.Blockscout]
url = "https://mcp.blockscout.com/mcp"
http_headers = { "Blockscout-MCP-Pro-Api-Key" = "<YOUR_BLOCKSCOUT_MCP_PRO_API_KEY>" }

Cursor

CURSOR · JSON

{
  "mcpServers": {
    "blockscout": {
      "url": "https://mcp.blockscout.com/mcp",
      "timeout": 180000,
      "headers": {
        "Blockscout-MCP-Pro-Api-Key": "<YOUR_BLOCKSCOUT_MCP_PRO_API_KEY>"
      }
    }
  }
}

Any MCP client — local Docker

ANY MCP CLIENT — LOCAL DOCKER · JSON

{
  "mcpServers": {
    "blockscout": {
      "command": "docker",
      "args": [
        "run",
        "--rm",
        "-i",
        "-e",
        "BLOCKSCOUT_PRO_API_KEY=<YOUR_BLOCKSCOUT_MCP_PRO_API_KEY>",
        "ghcr.io/blockscout/mcp-server:latest"
      ]
    }
  }
}

Blockscout

Chain data arrives already decoded: calls separated from token transfers, transaction input parsed, balances carrying their token metadata.

What it is

What you get

Requirements

Setup effort

Working out what a wallet actually holds

Tracing where a transfer ended up

Reading a contract you did not write

Pinning an event to a point in time

Starting from a name instead of an address

16 tools

__unlock_blockchain_analysis__

direct_api_call

get_address_by_ens_name

get_address_info

get_block_info

get_block_number

get_chains_list

get_contract_abi

get_token_transfers_by_address

get_tokens_by_address

get_transaction_info

get_transactions_by_address

inspect_contract_code

lookup_token_by_symbol

nft_tokens_by_address

read_contract

What to know first

Tools you get

Requires

Moderate Standing cost

Connect your client

Server setup

claude mcp add

Claude Code

Hosted endpoint

MCP Clients

Claude Desktop — Docker proxy

Codex

Cursor

Any MCP client — local Docker

Same category

Fuse Network

Universal Contract AI Interface (UCAI)

Blockchain MCP Server

OneSource MCP

`__unlock_blockchain_analysis__`

`direct_api_call`

`get_address_by_ens_name`

`get_address_info`

`get_block_info`

`get_block_number`

`get_chains_list`

`get_contract_abi`

`get_token_transfers_by_address`

`get_tokens_by_address`

`get_transaction_info`

`get_transactions_by_address`

`inspect_contract_code`

`lookup_token_by_symbol`

`nft_tokens_by_address`

`read_contract`