An MCP server for stock scores: what Coil’s server gives an AI agent

What is an MCP server for stock scores?

An MCP server for stock scores is a Model Context Protocol endpoint an AI agent can call for scored market data rather than raw prices: which names lead, which are at an entry, which are deteriorating, and whether the market as a whole is granting permission. Coil runs one at https://coil.trade/mcp. It is the machine-readable face of the same rules-based, long-only scanner and engine that publishes the coil.trade board, and its free tier serves the full board one market day delayed with no key, wallet or account. Live intraday reads have two doors, described below.

Add it in one line

In Claude Code the server is added with the HTTP transport named explicitly, exactly as a broker’s remote server is:

claude mcp add --transport http coil https://coil.trade/mcp

On Codex CLI the same server goes in with codex mcp add coil --url https://coil.trade/mcp; Claude Desktop and the other desktop clients take the URL in their connector settings. Then ask the agent to call get_morning_brief. Nothing on that line is a credential, and nothing on it can reach a brokerage account.

The free tools, and what each returns

Every free tool serves the board one market day delayed (the crypto trend tool is one daily close behind). No key, no wallet, no account.

• get_morning_brief — the whole market read in one call: regime verdict per book, today’s top five ranked candidates, the biggest movers and the crypto trend gate. The tool the server itself says to start with.
• get_market_regime — the top-down read: is the tape risk-on, be-selective or stand-down, per book, with the permission ladder that runs index, sector, name.
• get_buy_list — the ranked candidates per book across two lanes, each with buy, entry, growth and hold scores, a leadership flag and an entry-window note.
• get_stock_read — one stock’s full read: opportunity 0–100 and board percentile, entry quality and state, hold strength, leadership flag, and its book’s regime.
• get_market_leaders — the top ten leadership names per book by opportunity score, each with the full score read.
• get_sector_read — one sector drilled down: every member scored and ranked, plus the sector ETF’s own row.
• get_rotation — the sector and macro rotation map: about fifty ETFs scored on their ratio to SPY against that ratio’s 50-day and labelled GO, HOLDING, TURNING or OUT.
• get_day_board — the day-trade state map for about seventy liquid names: the intraday lights grid, GO, fuel against the anchor ETF, entry-window state and room to the next level.
• get_hold_state — the sell-side read for names you already hold: trend state, hold strength, readiness, a maturity-late flag and an overnight gap-risk grade.
• get_crypto_trend — the BTC and ETH long-only trend signal on UTC daily closes, with the 200-day master gate.
• get_crypto_day — a preview of the 24/7 crypto day-state board across the 81 Robinhood-tradable coins.
• get_crypto_night — a preview of the overnight continuation read into the 20:00 UTC signal.
• get_live_setup — how to connect this agent to Coil Live: what the subscription unlocks, how to send the key, the cadence, and what happens fail-closed. Free to call, no key needed.

The live twins: intraday, through two doors

Each market tool above has a _live twin recomputed about every 5 minutes in market hours, plus two live-only reads: get_full_board, the complete live board in one payload, and get_board_asof, the point-in-time archive of the scores Coil actually published on a past date, committed by hash before outcomes were known and never revised.

Door one is pay-per-call. The live tools answer a 402 with an x402 offer in USDC on Base, Solana or Algorand; the twins are priced in cents, the full board a dime, and no account is involved. The catalogue and current prices are on the For AI agents page and in /.well-known/coil.json, which every surface reads from.

Door two is the subscription. Coil Live ($29/mo or $249/yr) unlocks every live tool by an X-License-Key header and adds two tools that are never sold per call: get_engine_feed, the engine-grade board the live record trades from, with structural stop and target levels, risk-reward, conviction and lane for each served candidate, and get_live_rules, the versioned discipline the agent runs against it. get_live_setup explains the whole connection and is free to call.

What the scores are

The opportunity score is 0–100 with a board percentile. The entry window has five states: READY, SETUP, WAIT, CHASE and FALLING. Hold strength is a separate 0–100 read for names already held. The regime verdict is per book (risk-on, be-selective, stand-down) with a permission ladder from index to sector to name. The rotation map labels each sector and macro ETF GO, HOLDING, TURNING or OUT on its ratio to SPY. Every field is documented in the schema block each payload carries, and the strategy the scores serve is described on the deterministic strategy page.

What the server does not do

It has no brokerage tools. It cannot see, hold or trade an account; orders happen through your broker’s own connector, and Coil never sees them. The board carries no stop, target or position size at any tier; structural levels exist only in the licensed engine feed, and sizes are computed by the served rulebook from your equity. It gives no advice: every payload is impersonal research, published for all subscribers alike. And it never rewrites history: the archive tool serves what was published, hash-committed before the outcome.

The polling contract

Every board-derived response carries a freshness block: whether the market is open, how old the data is in seconds, and next_refresh_at, the time to come back. The live board recomputes about every 5 minutes in market hours, so polling faster returns the same payload; the free board changes once per market day. A free change-detection hash at /api/board/state lets an agent poll cheaply and read only when something moved.

Pairing it with a broker’s MCP

The two servers load into the same client. The read order that keeps them in the right relationship is regime first, then the ranked list, then the broker’s tools last: Coil’s selection before the broker’s execution, never the other way around. The pairing recipe for Robinhood agentic trading gives the copy-paste version, and the setup guide covers the broker side, guardrails included.

Other ways in

The same data is served over plain HTTP: GET https://coil.trade/api/board/free is the free sample, a free API key from POST https://coil.trade/api/key adds a daily allowance of live calls by header, and the full REST surface is described in /openapi.json. Agents that read documents first can start at /llms.txt. The server is listed in the MCP registry as trade.coil/stock-market-scanner, and the human-readable overview of all of it is the For AI agents page.

FAQ

Is there a free MCP server for stock data?

Yes. Coil's MCP server at https://coil.trade/mcp has a free tier with no key, wallet or account: the full scored board (market regime, ranked buy list, per-stock reads, market leaders, sector and rotation maps, the day board and the crypto trend gate), one market day delayed. Add it to Claude Code with claude mcp add --transport http coil https://coil.trade/mcp and call get_morning_brief.

Does the Coil MCP server need an API key?

Not for the free tier. The live intraday tools are unlocked either by paying per call over x402 in USDC (no account) or by a Coil Live subscription, whose Gumroad licence key is sent as the X-License-Key header. The tool get_live_setup explains the connection and is itself free to call.

Can an MCP server place trades?

A broker's MCP server can; Coil's cannot. Coil's server serves scores and rules and has no brokerage tools, so it never sees or touches an account. In an agentic setup the agent reads Coil first, then places any order itself through the broker's own connector, such as Robinhood's agentic trading MCP.

How fresh is the free tier?

One market day delayed, published on the same cadence as the board. The live twins recompute about every 5 minutes during US market hours, and every payload carries a freshness block with the data age and the time to poll again, so an agent never has to guess.

Which AI agents can use it?

Any MCP client that speaks streamable HTTP: Claude Code, Claude Desktop, Codex and Codex CLI, Cursor and the others that connect to remote servers by URL. The same data is also served over plain HTTP for agents that do not use MCP at all.