lighter-mcp

lighter-mcp

An MCP server that gives an agent read access to Lighter markets and a guarded path to place orders, including market 182, the perpetual on NVIDIA H100 rental cost.

Built by Prism. Not affiliated with, endorsed by, or operated by Lighter or elliottech.

Run it

npx -y lighter-mcp

Node 20 or newer. The server speaks MCP over stdio and writes diagnostics to stderr.

Client configuration

{
  "mcpServers": {
    "lighter": {
      "command": "npx",
      "args": ["-y", "lighter-mcp"],
      "env": {
        "LIGHTER_NETWORK": "mainnet"
      }
    }
  }
}

Tools

Tool	Arguments	Signs
lighter_markets	query, limit	no
lighter_market	market_id or symbol, depth	no
lighter_h100	none	no
lighter_funding	market_id or symbol, history_limit	no
lighter_account	account_index, optional market selector	no
lighter_place_order	market selector, side, size, order_type, price, max_notional_usd	yes
lighter_cancel	market selector, order_index	yes
lighter_cancel_all	none	yes
lighter_hedge_h100	gpu_hours, side, max_notional_usd, execute	only when execute is true

Lighter cancels account-wide, so lighter_cancel_all clears every market and cannot be scoped to one. Order indexes travel as decimal strings, since they exceed the safe integer range.

lighter_markets reads Lighter's market-detail route. That route carried 229 markets on mainnet on 2026-08-26, and the response reports the live count.

lighter_funding returns Lighter's own rates. The same route carries Binance, Bybit, and Hyperliquid for reference, and those rows are left out, since a position opened here collects Lighter's rate.

Responses are JSON, capped at 16,000 characters. Long lists are shortened and the count of omitted items is reported, so a full market listing cannot flood the context.

Environment

Variable	Required	Purpose
LIGHTER_NETWORK	no	mainnet, testnet, or robinhood. Defaults to mainnet
LIGHTER_ACCOUNT_INDEX	for signing	Sub-account the agent trades from
LIGHTER_API_KEY_INDEX	for signing	API key slot, 0 to 254
LIGHTER_API_KEY_PRIVATE_KEY	for signing	API key private key
LIGHTER_MAX_NOTIONAL_USD	for signing	Per-order notional ceiling, no default
LIGHTER_CHAIN_ID	on robinhood	Layer-2 chain id bound into every signature
LIGHTER_READ_ONLY_TOKEN	no	Read account state without a signing key

Set all four signing variables or none. A partial set stops the server at startup with a message naming what is missing, rather than starting in a state where an order fails halfway through.

Mainnet signs against chain id 304 and testnet against 300, so LIGHTER_CHAIN_ID is only there to override them. Lighter on Robinhood Chain publishes no chain id, so signing there needs one, and the server stops at startup instead of letting the first order fail at the signer.

How the write path is guarded

• lighter_place_order and lighter_hedge_h100 require max_notional_usd on every call. There is no default and no way to opt out.
• The order is priced against one book snapshot and checked as a dry run. A worst-case notional above the ceiling is refused before a signature exists, and the order that is signed is the one that was checked.
• The server applies its own LIGHTER_MAX_NOTIONAL_USD as a second ceiling, and the lower of the two wins.
• lighter_hedge_h100 returns a plan and sends nothing unless execute is true.
• There is no transfer tool and no change-pubkey tool.

A Lighter API key is full write authority over the account it is bound to, so run this server against a dedicated sub-account funded with only what the agent may lose.

Limitations

The H100 book is thin. Measured on 2026-08-26 it traded about $7,100 over 24 hours, held open interest near $10,000, and showed 4.00 of size at the top of book on each side. Lighter's Standard rate tier allows 60 requests per minute, so the server caches the market list for 30 seconds.

License

Apache-2.0. See LICENSE and NOTICE.