@one-source/mcp

Unified MCP server for OneSource — 31 tools for blockchain data, live chain queries, and API documentation in a single server.

Combines @one-source/api-mcp (22 tools) and @one-source/docs-mcp (9 tools) so your AI assistant gets full access to OneSource with one MCP connection.

What is MCP? The Model Context Protocol lets AI assistants call tools and access data sources. This server exposes both the OneSource blockchain API and its documentation as tools.

Quick Start

Claude Code

claude mcp add onesource -- npx @one-source/mcp

Claude Desktop / Cursor

Add to your MCP config:

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

Any MCP Client (stdio)

npx @one-source/mcp

HTTP Server (self-hosted)

npx @one-source/mcp --http
npx @one-source/mcp --http --port=8080

Then connect your MCP client to http://localhost:3000/.

Tools (31)

Blockchain API — Live Chain (12 tools)

| Tool | Description | |------|-------------| | 1s_allowance_live | ERC20 allowance check | | 1s_contract_info_live | Contract type detection via ERC165 | | 1s_erc1155_balance_live | ERC1155 balance via RPC | | 1s_erc20_balance_live | ERC20 balance via balanceOf | | 1s_erc20_transfers_live | ERC20 Transfer logs via eth_getLogs | | 1s_erc721_tokens_live | ERC721 token enumeration | | 1s_events_live | Event logs via eth_getLogs | | 1s_multi_balance_live | ETH + multiple ERC20 balances | | 1s_nft_metadata_live | NFT metadata via tokenURI | | 1s_nft_owner_live | NFT owner via ownerOf | | 1s_total_supply_live | Token total supply | | 1s_tx_details_live | Transaction + receipt via RPC |

Blockchain API — Chain Utilities (10 tools)

| Tool | Description | |------|-------------| | 1s_contract_code | Contract bytecode | | 1s_ens_resolve | ENS name/address resolution | | 1s_estimate_gas | Gas estimation | | 1s_network_info | Chain ID, block number, gas price | | 1s_nonce | Transaction count | | 1s_pending_block | Pending block from mempool | | 1s_proxy_detect | Proxy contract detection | | 1s_simulate_call | Simulate eth_call | | 1s_storage_read | Read storage slot | | 1s_tx_receipt | Transaction receipt |

Documentation (9 tools)

Read-only, no API key required.

| Tool | Purpose | When to use | |------|---------|-------------| | search_docs | Keyword search across all documentation | Finding guides, concepts, or API patterns | | get_query_reference | Full reference for a root GraphQL query | Building a specific query with correct args/filters | | get_type_definition | Schema definition for any type/enum/input | Understanding field shapes and return types | | list_examples | Browse or search working GraphQL examples | Finding ready-to-use query patterns | | list_supported_chains | All supported blockchain networks + endpoints | First question: "What chains are supported?" | | get_filter_reference | Filter fields and operators for a list query | Building filtered queries with correct syntax | | get_pagination_guide | Cursor-based pagination pattern with examples | Implementing pagination for list queries | | get_schema_overview | High-level summary of the entire schema | Exploring the API surface before diving in | | get_authentication_guide | API key format, headers, and endpoints | Setting up authentication for the first time |

Networks

All blockchain API tools accept an optional network parameter:

| Network | Description | |---------|-------------| | ethereum | Ethereum mainnet (default) | | sepolia | Ethereum Sepolia testnet | | avax | Avalanche C-Chain |

Payment (x402)

Blockchain API endpoints are priced in USDC on Base via x402. When the backend has payments enabled, tool calls return a 402 with payment details. Agents using @x402/fetch handle this automatically.

Documentation tools are always free — no API key or authentication needed.

License

Apache 2.0