OneSource MCP

@one-source/mcp

Unified MCP server for OneSource — 30 tools for blockchain data and live chain queries in a single server.

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 -y @one-source/mcp@latest

Claude Desktop / Cursor

Add to your MCP config:

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

Any MCP Client (stdio)

npx -y @one-source/mcp@latest

HTTP Server (self-hosted)

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

Then connect your MCP client to http://localhost:8080/.

Health check: GET http://localhost:8080/health

Tools (30)

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 (13 tools)

RPC only.

Tool	Description
1s_block_by_number	Block details by number via RPC
1s_block_number	Latest block number
1s_chain_id	EIP-155 chain ID
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

Payments (2 tools)

Tool	Description
1s_payment_mode	View or switch the payment rail + scheme across all four modes: x402-exact / x402-batch (USDC on Base) and mpp-charge / mpp-session (USDC.e / pathUSD on Tempo). batch and session open a channel that funds many calls.
1s_refund	Reclaim an open payment channel's unspent deposit on demand — works for both an x402 batch channel (Base) and an MPP session voucher channel (Tempo)

Setup & Ops (3 tools)

No authentication required.

Tool	Purpose	When to use
1s_setup_check	Interactive setup & health check. Walks the user through every configuration choice for both rails (auth method, x402, MPP, payment modes, channel prefs) one decision at a time — every run, even when already configured — plus version, auth status, channel status, and connectivity	First thing to call — to set up, change configuration, or troubleshoot
1s_batch_config	View or change payment-channel preferences (autonomy, threshold, x402 deposit multiplier, MPP session deposit cap, default mode) and persist them across restarts — no config editing required	Configure channel behaviour from the session
1s_report_bug	Report bugs to Slack (or GitHub Issues fallback)	When a tool errors or user wants to report an issue

Networks

All blockchain API tools accept an optional network parameter:

Network	Description
ethereum	Ethereum mainnet (default)
sepolia	Ethereum Sepolia testnet

Authentication

Blockchain API tools require authentication. Three options are available — if an API key is set alongside a wallet key, the API key takes priority and the wallet is ignored.

Tip: the fastest way to configure any of these is the 1s_setup_check tool — it walks you through every option interactively and hands you a ready-to-run command, so you never have to hand-edit env vars or config files. The manual instructions below are the reference.

Method	Variable	Description
API key	ONESOURCE_API_KEY	Unlimited calls, no per-call cost
x402 micropayments	X402_PRIVATE_KEY	Pay-per-call via USDC on Base, no account required
MPP micropayments	MPP_PRIVATE_KEY	Pay-per-call via USDC.e / pathUSD on Tempo, no account required

Option 1: API Key

1. Go to app.onesource.io and create an account.
2. Subscribe to a developer plan (Stripe checkout).
3. Navigate to API Keys and generate a key.
4. Copy the key — it starts with sk_.

Claude Code

claude mcp add onesource -e ONESOURCE_API_KEY= -- npx -y @one-source/mcp@latest

Claude Desktop / Cursor

Add the env block to your MCP config:

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

Any MCP Client (stdio)

ONESOURCE_API_KEY= npx -y @one-source/mcp@latest

After adding, reload the MCP server and call 1s_setup_check — under Current configuration it should report Active auth method: API key (with the first 6 characters of your key).

Option 2: x402 Micropayments

Blockchain API endpoints are priced in USDC on Base via x402. When you set X402_PRIVATE_KEY, the server automatically handles payments — tool calls are paid and retried transparently without any extra work from the agent.

1. Get an EVM private key — export one from MetaMask, Coinbase Wallet, or any EVM wallet, or generate a fresh one. The key is a 64-character hex string. The 0x prefix is optional — both formats are accepted.
2. Pass the key to the server using one of the methods below.
3. Reload and find your wallet address — reload the MCP server, then call 1s_setup_check. Under Current configuration it lists your x402 (Base) wallet — the address derived from your key.
4. Fund that address with USDC on Base — send USDC to the address shown in 1s_setup_check, on the Base network. A few dollars ($1–5 USDC) is enough for hundreds of calls. If your USDC is on Ethereum mainnet, bridge it using the Base Bridge.
5. Verify — call 1s_network_info for ethereum. If it returns chain data (block number, gas price), x402 payments are working end-to-end.

Claude Code

claude mcp add onesource -e X402_PRIVATE_KEY= -- npx -y @one-source/mcp@latest

{ "mcpServers": { "onesource": { "command": "npx", "args": ["-y", "@one-source/mcp@latest"], "env": { "X402_PRIVATE_KEY": "" } } } }

X402_PRIVATE_KEY= npx -y @one-source/mcp@latest

Option 3: MPP Micropayments (Tempo)

Blockchain API endpoints can also be paid on the Tempo network via MPP — an alternative to x402 on Base. When you set MPP_PRIVATE_KEY, the server handles payments automatically; tool calls are paid and retried transparently.

1. Get an EVM private key — same format as x402 (64-char hex, 0x optional). Export one or generate a fresh key.
2. Pass the key to the server using one of the methods below.
3. Reload and find your wallet address — reload the MCP server, then call 1s_setup_check. Under Current configuration it lists your MPP (Tempo) wallet — the address derived from your key.
4. Fund that address with USDC.e or pathUSD on Tempo — a few dollars covers hundreds of calls.
5. Verify — call 1s_network_info. If it returns chain data, MPP payments are working end-to-end.

Claude Code

claude mcp add onesource -e MPP_PRIVATE_KEY= -- npx -y @one-source/mcp@latest

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

MPP_PRIVATE_KEY= npx -y @one-source/mcp@latest

By default MPP pays per call (mpp-charge). For a burst of calls, switch to a Tempo voucher channel with 1s_payment_mode { "mode": "mpp-session" } (or set MPP_PAYMENT_MODE=session) — one deposit funds many off-chain calls; reclaim the unspent balance any time with 1s_refund, or it settles automatically on clean shutdown.

Config File Locations

If you prefer editing the config file directly instead of using CLI commands:

Client	Config file path
Claude Code	Run claude mcp get onesource to see the file path
Claude Desktop (macOS)	~/Library/Application Support/Claude/claude_desktop_config.json
Claude Desktop (Windows)	%APPDATA%\Claude\claude_desktop_config.json
Cursor (macOS)	~/.cursor/mcp.json
Cursor (Windows)	%USERPROFILE%\.cursor\mcp.json

Add the onesource entry inside "mcpServers" using the JSON block shown above.

Alternative: Set as an Environment Variable

Instead of the env config block, you can set any of these variables as a shell or system environment variable: export ONESOURCE_API_KEY=<key> (bash/zsh) or $env:ONESOURCE_API_KEY = "<key>" (PowerShell). Set it at the OS level for persistence across sessions.

Payment channels (optional)

By default each paid call signs one payment per call (x402-exact on Base, mpp-charge on Tempo). For a burst of calls, open a payment channel — one on-chain deposit funds many off-chain calls, settled together — which is cheaper than paying per call:

• x402 (Base): switch to x402-batch with 1s_payment_mode { "mode": "x402-batch" } (or X402_PAYMENT_MODE=batch). The first call deposits price × X402_DEPOSIT_MULTIPLIER (default 10).
• MPP (Tempo): switch to mpp-session with 1s_payment_mode { "mode": "mpp-session" } (or MPP_PAYMENT_MODE=session). The first call deposits up to MPP_MAX_DEPOSIT (default 1).

Reclaim the unused balance any time with the 1s_refund tool (works for both rails); the residual is always recoverable on-chain. An idle x402 channel also auto-refunds after a few hours, and an MPP session settles automatically on clean shutdown.

When paying via a wallet, the agent receives channel guidance in its system prompt at startup, so it can manage this for you rather than leaving it as a manual step: when it anticipates a burst of calls it offers to switch to the channel mode for the active rail and reminds you to 1s_refund when finished. Control how proactive it is with X402_BATCH_PROMPT (ask / auto / off) and X402_BATCH_THRESHOLD (how many anticipated calls count as a burst — shared across both rails) — see Environment Variables. 1s_setup_check reports your current mode, whether the channel is available, and all settings.

Security

Never commit keys to source control. Use environment variables, a .env file (excluded from git), or a secrets manager.

After any config change: Run /reload-plugins in Claude Code, or restart Claude Desktop / Cursor. The MCP server must be reloaded to pick up new environment variables.

Environment Variables

Required

Set one to access the blockchain API tools. Without any, only the no-auth Setup & Ops tools work. The API key takes priority when set alongside a wallet key.

Variable	Default	Description
ONESOURCE_API_KEY	—	OneSource API key for Bearer token auth. Takes priority over the wallet rails.
X402_PRIVATE_KEY	—	EVM private key (64-char hex, 0x prefix optional) for automatic x402 USDC payments on Base.
MPP_PRIVATE_KEY	—	EVM private key for automatic MPP payments (USDC.e / pathUSD) on Tempo.

Optional / Advanced

All have sensible defaults — channel modes run out of the box. Set these only to override an endpoint, tune how channel modes behave, or adjust analytics. Payment modes can also be switched at runtime with the 1s_payment_mode tool. The channel knobs below (X402_PAYMENT_MODE, X402_DEPOSIT_MULTIPLIER, MPP_PAYMENT_MODE, MPP_MAX_DEPOSIT, X402_BATCH_PROMPT, X402_BATCH_THRESHOLD) can be set and persisted from a session with the 1s_batch_config tool — no config editing or restart required; a saved config takes priority over these env vars.

Variable	Default	Description
ONESOURCE_BASE_URL	https://api.onesource.io	API base URL.
X402_PAYMENT_MODE	exact	Initial x402 scheme: exact (per-call) or batch (payment channel). Switch in-session with 1s_payment_mode.
X402_RPC_URL	Base default	Base RPC endpoint used to submit channel deposits in batch mode.
X402_DEPOSIT_MULTIPLIER	10	Batch mode: deposit = price × this multiplier, funding that many calls per channel. Unused balance is reclaimable via 1s_refund.
X402_CHANNEL_DIR	—	Directory to persist batch channel state across restarts. Unset = in-memory (channel lost on restart).
X402_CHANNEL_SALT	zero	Batch mode: 32-byte hex salt to derive the starting channel id. The client auto-rotates to the next salt when a channel is exhausted or refunded.
MPP_PAYMENT_MODE	charge	Initial MPP scheme: charge (per-call) or session (Tempo voucher channel). Switch in-session with 1s_payment_mode.
MPP_MAX_DEPOSIT	1	Session mode: max USDC.e / pathUSD locked per Tempo voucher channel. Unused balance is reclaimable via 1s_refund.
MPP_RPC_URL	Tempo default	Tempo RPC endpoint used to submit channel deposits in session mode.
X402_BATCH_PROMPT	ask	How the agent handles switching to a channel mode (both rails): ask (confirm before switching), auto (switch on its own), or off (only switch when explicitly asked).
X402_BATCH_THRESHOLD	5	Number of anticipated calls in a session at/above which the agent considers a channel mode (both rails). Advisory — the agent estimates the call count; it is not a hard runtime counter.
ONESOURCE_CONFIG_DIR	~/.onesource	Directory holding the server-managed channel config (batch-config.json) written by 1s_batch_config.
ONESOURCE_ANALYTICS	true	Set to false to disable analytics.
ONESOURCE_ANALYTICS_URL	https://1s-analytics.vercel.app	Dashboard endpoint for analytics.
X402_ANALYTICS_KEY	onesource-mcp	API key for dashboard analytics.

Troubleshooting

**1s_setup_check shows "Active auth method: none" (blockchain tools locked)**Under Current configuration, "Active auth method: none" means no authentication is set. Set one of ONESOURCE_API_KEY (API key), X402_PRIVATE_KEY (x402 on Base), or MPP_PRIVATE_KEY (MPP on Tempo) — or just run 1s_setup_check and let it walk you through it. Reload the MCP server after setting any variable (see note above). If the key still isn't reaching the server, set it as a shell environment variable directly.

Getting 403 / wrong key active despite correct setupA key set in your shell profile (e.g. ~/.zshrc, ~/.bash_profile) is picked up by the MCP server process even if it isn't in your Claude MCP config. Run echo $ONESOURCE_API_KEY in your terminal to check. If it prints a value you didn't intend, unset it (unset ONESOURCE_API_KEY) or explicitly clear it when adding the server: claude mcp add onesource -e ONESOURCE_API_KEY= -e X402_PRIVATE_KEY=<key> -- npx -y @one-source/mcp@latest. 1s_setup_check shows the first 6 characters of whichever key is active so you can confirm which one the server is using.

Instructions show wrong auth method after reinstall /reload-plugins in Claude Code reconnects tools but may not refresh the system prompt the LLM sees. If you switch auth method (e.g. API key → x402), do a full Claude Code restart to ensure the instructions reflect the new auth.

"MCP server onesource already exists" errorRun claude mcp remove onesource first, then re-add with your updated config.

Windows: npx requires cmd /c wrapperClaude Code's /doctor command may warn about this. Update your MCP config to use "command": "cmd" with "args": ["/c", "npx", "-y", "@one-source/mcp@latest"].

**npx hangs with no output** That's normal — stdio mode waits for JSON-RPC input on stdin. Use --http if you want an HTTP server you can curl.

Port already in useSpecify a different port: npx -y @one-source/mcp@latest --http --port=8080

Registry Publishing

This package is listed on the official MCP Registry under the verified namespace io.onesource/mcp and on Glama. When releasing a new version, update both registries.

MCP Registry

First-Time Setup

1. Install Go

Download the installer for your platform from go.dev/dl and run it. Verify:

go version

2. Install mcp-publisher

go install github.com/modelcontextprotocol/registry/cmd/mcp-publisher@latest

If the Go module path has changed and the command fails, download the binary directly from the mcp-publisher GitHub releases page instead.

On Windows, add Go's bin directory to your PATH if the command isn't recognized:

$env:PATH += ";$env:USERPROFILE\go\bin"

Verify:

mcp-publisher --help

3. DNS Authentication (already done)

The onesource.io domain has a DNS TXT record that proves ownership of the io.onesource namespace. This is already configured — you don't need to redo it.

The record is on the root domain (onesource.io, not _mcp-registry.onesource.io):

v=MCPv1; k=ed25519; p=7D3U5rufgNXb/lH2MthTRZdDzEGeE7/Jvg8YkiArQc8=

You can verify it resolves:

nslookup -type=TXT onesource.io 8.8.8.8

4. Get the Private Key

Authentication requires the ed25519 private key in hex format that corresponds to the public key in the DNS record. Ask the team lead for this key — it's stored in the team's password manager / vault.

If you need to regenerate the keypair (this invalidates the current DNS record and requires updating it):

1. Generate a new ed25519 keypair (e.g., openssl genpkey -algorithm Ed25519 -out key.pem)
2. Extract the raw 32-byte private key seed and convert to hex:

openssl pkey -in key.pem -outform DER | tail -c 32 | xxd -p -c 32

1. Extract the public key in base64 for the DNS TXT record:

openssl pkey -in key.pem -pubout -outform DER | tail -c 32 | base64

1. Update the DNS TXT record on onesource.io with the new public key:

 v=MCPv1; k=ed25519; p=<base64-public-key>

1. Wait for DNS propagation before attempting to log in.

Publishing a New Version

Use the release script. Releases are normally run via the coordinated release script in the sre-services repo (scripts/release-mcp.mjs — see sre-services/RELEASING.md), which performs all of the steps below across both @one-source/api-mcp and@one-source/mcp in the correct order, including the server.json bump andmcp-publisher publish. The First-Time Setup above is still the prerequisite for the registry step. The manual steps below are the fallback for registry-only fixes or when the script can't run.

Every time you release a new npm version, update the MCP Registry:

1. Publish to npm (the registry validates the package exists, so this must happen first):

npm run build npm publish --access public

1. Update server.json — set both version fields to match the new npm version:

{ "version": "x.y.z", ... "packages": [{ "version": "x.y.z", ... }] }

The mcpName field in package.json must be "io.onesource/mcp" and must match the name field in server.json. This is already set — don't remove it. 3. Authenticate (tokens expire, so do this each time):

mcp-publisher login dns --domain onesource.io --private-key

1. Publish to the registry:

mcp-publisher publish

1. Verify:

curl "https://registry.modelcontextprotocol.io/v0.1/servers?search=onesource"

Glama

Glama auto-syncs from the GitHub repo daily. No manual steps needed after a release — just make sure changes are pushed to main. The glama.json file in the repo root controls ownership. Manual re-sync is available from the Glama admin panel after claiming the server.

Privacy Policy

Use of this extension connects to the OneSource API. See the OneSource Privacy Policy for details on how data is handled.

License

Apache 2.0 — see LICENSE for details.