3xpl.Com JSON API MCP Server

A Model Context Protocol (MCP) server for querying data from 48 blockchains using 3xpl.com blockchain explorer JSON API

Local serverstdio

What is the 3xpl.Com JSON API MCP server?

A Model Context Protocol (MCP) server for querying data from 48 blockchains using 3xpl.com blockchain explorer JSON API. The 3xpl.com json api mcp server wraps that behind the Model Context Protocol, so an assistant can use it through 14 defined tools rather than through you.

What it actually does

This repository can also be an example of 3xpl JSON API usage, see details in the code.

Its toolset

Everything the assistant can do here goes through one of these:

  • resolve_ens_domain — resolves an ENS domain to a regular address
  • detect_blockchains — retrieve a list of blockchains on which a transaction/address is present
  • get_latest_block — get latest block height in specified blockchain
  • get_average_fee_24h_usd — retrieves average transaction fee for last 24 hours in specified blockchain in US dollars
  • get_mempool_events_count — get the number of unconfirmed events(transfers, inputs/outputs, not transactions) at the moment in the memory pool of provided blockchain
  • get_events_count_24h — retrieve number of events(transfers, inputs/outputs, not whole transactions) in last 24h for provided blockchain
  • get_block_overview — extract short summary about a block in provided blockchain
  • get_address_overview — extract short summary about an address in provided blockchain
  • get_transaction_overview — extract short summary about a transaction in provided blockchain(to be improved)
  • list_blockchains_and_modules — get a list of blockchains and their modules with module descriptions
  • aggregate_block_transactions — aggregate transactions in a block
  • aggregate_transaction_transfers — aggregate individual transfers in a transactions

Configuration

You will need one environment variable: THREEXPL_API_KEY. The server will not start without them, which is usually why the tools fail to appear on a first run. Keep credentials in your client's env block or a secrets manager rather than in a file you might commit.

Adding it to your client

Setup follows the usual MCP pattern — install or clone the server, register it in your client's configuration file, restart the client. The configuration blocks on this page cover the common clients.

When to reach for it

Among the knowledge and memory options, the useful question is rarely "what can it do" but "what does it cost you to run" — permissions, credentials, and how much of your context its toolset consumes. 3xpl.Com JSON API's toolset — resolve_ens_domain, detect_blockchains, get_latest_block and 11 more — is a fair guide to whether it matches your workflow. It is maintained by exekerey; worth a glance at recent repository activity before you build anything load-bearing on it.

This entry was verified against 3xpl.Com JSON API's own documentation before publication; SyncDev keeps the directory reviewed rather than auto-generated.

Caveats

  • It runs with your machine's permissions. That is convenient and also the reason to think about what you point it at before you approve a tool call.
  • With 14 tools registered it takes up a noticeable share of the context window; turn it off in projects that never touch 3xpl.Com JSON API.
  • Missing credentials fail quietly in some clients — if no tools show up, check the environment block first.
  • MCP clients confirm each tool call by default. Leave that on until you have watched what the 3xpl.com json api mcp server does with a few real requests.

Available tools

ToolWhat it does
resolve_ens_domainresolves an ENS domain to a regular address
detect_blockchainsretrieve a list of blockchains on which a transaction/address is present
get_latest_blockget latest block height in specified blockchain
get_average_fee_24h_usdretrieves average transaction fee for last 24 hours in specified blockchain in US dollars.
get_mempool_events_countget the number of unconfirmed events(transfers, inputs/outputs, not transactions) at the moment in the memory pool of provided blockchain
get_events_count_24hretrieve number of events(transfers, inputs/outputs, not whole transactions) in last 24h for provided blockchain
get_block_overviewextract short summary about a block in provided blockchain
get_address_overviewextract short summary about an address in provided blockchain
get_transaction_overviewextract short summary about a transaction in provided blockchain(to be improved)
list_blockchains_and_modulesget a list of blockchains and their modules with module descriptions
aggregate_block_transactionsaggregate transactions in a block
aggregate_transaction_transfersaggregate individual transfers in a transactions
aggregate_address_balancesaggregate balances for an address with
aggregate_address_transactionsaggregate confirmed transactions for an address

How to install the 3xpl.Com JSON API MCP server

MCP configuration:

```json
{
  "mcpServers": {
    "3xpl_API": {
      "command": "uv",
      "args": [
        "run",
        "--with",
        "mcp[cli]",
        "mcp",
        "run",
        "{:path_to_cloned}/3xpl_mcp/main.py"
      ],
      "env": {
        "THREEXPL_API_KEY": ""
      }
    }
  }
}

Configuration as documented by the project. Restart the client after saving.

Configuration

VariableDescriptionRequired
THREEXPL_API_KEYCredential the server authenticates with.Yes

Example prompts to try

  • Use 3xpl.Com JSON API to resolve ens domain.
  • Use 3xpl.Com JSON API to detect blockchains.
  • Use 3xpl.Com JSON API to get latest block.

Frequently asked questions

An API key from 3xpl is required for the main API. If left blank, the server uses the sandbox API, which has rate limits.