Polymarket US
Polymarket US only. This toolkit connects to the CFTC-compliant Polymarket US product for United States users, not the global Polymarket app. API credentials are created at https://polymarket.us/developers after Polymarket US account verification.
Verdict
Common use cases
- Preview order impact before placing trades
- Cancel open positions across multiple markets
- Monitor account balances and buying power
- Pull trade history for portfolio review
- Close positions after event resolution
Integration
- Vendor
- Polymarket US
- Category
- other
- Auth
- API_KEY
- Tools
- 44
- Composio slug
polymarket
Tools
- Cancel All Open Orders
Cancel all authenticated Polymarket US open orders, optionally scoped to specific market slugs. This is broad and destructive for remaining open quantities; omit slugs only when the user clearly asks to cancel every open order. Already exec
- Cancel Multiple Orders
Cancel up to 20 Polymarket US open orders in one request. Use only when the user explicitly asks to cancel the batch. Cancellation removes remaining open quantity but does not undo fills or positions, and batch responses can require per-ord
- Cancel Order
Cancel one Polymarket US open order by exchange-assigned order ID. This is a destructive mutation of the remaining open quantity and should only be used when the user explicitly asks to cancel. Already executed fills and resulting positions
- Close Position Order
Create a live Polymarket US order intended to close an existing position in one market. Use only when the user explicitly asks to close that position. This can trade immediately, leave residual exposure if not fully filled, or be rejected f
- Create Multiple Orders
Submit up to 20 live Polymarket US orders in one request. Use only after the user explicitly asks to place the batch and, when practical, after previewing the same orders. This mutating action can consume buying power and create exposure ac
- Create Order
Submit one live Polymarket US order. Use Preview Order first unless the user has already reviewed the exact order details. This mutating action can reserve buying power, fill immediately, or create real market exposure; the API may also rej
- Get Account Balances
Get the authenticated user's Polymarket US account balances. Use this read-only action to inspect buying power, balances, pending credits, and funds reserved by open orders before previewing or placing orders. Requires Polymarket US signed
- Get Activities
Get authenticated Polymarket US portfolio activities such as trades, resolutions, deposits, withdrawals, referral bonuses, and transfers. Requires Polymarket US signed authentication and returns activity only for that account. Use type filt
- Get Event By ID
Get one Polymarket US event by numeric ID from the public gateway API. Use this after discovery when the caller already has the integer event ID and needs full event details or associated market references. Do not pass slugs here; use Get E
- Get Event By Slug
Get one Polymarket US event by slug from the public gateway API. Use this after search/list discovery or when parsing a Polymarket event URL. Do not pass numeric IDs here; use Get Event By ID for integer IDs. This read-only action does not
- Get League By Slug
Get a current Polymarket US v2 league by slug. Use List Leagues or Get Sport By Slug first if the slug is unknown. This is useful for confirming league metadata before listing events for a league such as "nba" or "nfl". This action does not
- Get Market BBO
Get the best bid and offer for one Polymarket US market by slug. Use this lightweight top-of-book read before quoting, previewing, or explaining an order. If the agent needs depth or slippage context, use Get Market Book instead. The respon
- Get Market Book
Get the public order book for one Polymarket US market by slug. Use this before quoting, previewing, or explaining an order when the agent needs depth beyond the top of book. The response is market data, not an order placement or order prev
- Get Market By ID
Get one Polymarket US market by numeric ID from the public gateway API. Use this after market discovery when the caller already has the integer market ID and needs full market metadata. Do not pass slugs here; use Get Market By Slug for slu
- Get Market By Slug
Get one Polymarket US market by slug from the public gateway API. Use this after search/list discovery or when parsing a Polymarket market URL. Do not pass numeric IDs here; use Get Market By ID for integer IDs. For current pricing before q
- Get Market Settlement
Get settlement information for one Polymarket US market by slug. Use this only for resolved, closed, or historical market workflows where the caller needs public resolution or settlement details. It is not useful for discovering current mar
- Get Markets For Subject
Discover Polymarket US markets associated with a subject ID. Use this action after List Subjects or Get Subject By ID identifies the team, person, candidate, player, nominee, or other entity the user cares about. This is a market discovery
- Get Markets For Subject By Slug
Discover Polymarket US markets associated with a subject slug. Use this action after List Subjects, Get Subject By Slug, or a Polymarket URL identifies the team, person, candidate, player, nominee, or other entity the user cares about. This
- Get Open Orders
Get all open orders for the authenticated Polymarket US user. Use this read-only action before modifying or canceling orders, or to inspect live order exposure. Requires signed authentication, supports optional market slug filters, and does
- Get Order
Get an authenticated user's Polymarket US order by exchange-assigned order ID. Requires signed authentication and returns order details available to that account. Use this read-only action to inspect order state after creating, modifying, o
- Get Series By ID
Get a Polymarket US series by numeric ID. Series are recurring or grouped event collections. Use this action when an agent has a series ID and needs the slug, active status, recurrence, or other public metadata before fetching related event
- Get Sport By Slug
Get a current Polymarket US v2 sport by slug. Use List Sports first if the slug is unknown. The response includes the sport metadata and leagues attached to that sport, which helps agents move from broad sport browsing to league-specific ev
- Get Subject By ID
Get a Polymarket US subject entity by numeric ID. Subjects represent teams, people, candidates, players, nominees, and other named entities attached to markets. Use this action when an agent already has a subject ID and needs its slug, type
- Get Subject By Slug
Get a Polymarket US subject entity by slug. Subjects represent teams, people, candidates, players, nominees, and other named entities attached to markets. Use this action when an agent has a subject slug from a URL or search result and need
- Get Tag By ID
Get a Polymarket US topic, sport, or league tag by numeric ID. Use this action after List Tags or a market/event response returns a tag ID and the agent needs the tag label, slug, hierarchy, or sport/league metadata for filtering or display
- Get Tag By Slug
Get a Polymarket US topic, sport, or league tag by slug. Use this action when an agent has a URL-safe tag slug, such as nba or sports, and needs the tag ID, label, hierarchy, or sport/league metadata for filtering or display. This action do
- Get User Positions
Get the authenticated user's Polymarket US trading positions across all markets or filtered by a specific market slug. Requires Polymarket US signed authentication and only returns positions for that account. Use this read-only action to ve
- List Events
Discover Polymarket US events from the public gateway API. Use this action before event-specific lookups when starting from a topic, category, tag, or broad filter set. Practical guidance for agents: - For currently relevant events, start w
- List Events For League
List Polymarket US events for a current v2 league slug such as "nba" or "nfl". Use List Leagues or Get Sport By Slug first if the slug is unknown. Supports limit/offset pagination, excludeEventId for de-duplicating already-seen events, and
- List Events For Series
List Polymarket US sports events for a legacy v1 series ID. Prefer List Events For Sport or List Events For League for current v2 browsing. Use this action when an agent already has a series ID from a legacy sports workflow and needs relate
- List Events For Sport
List Polymarket US events for a current v2 sport slug such as "football" or "basketball". Use List Sports first if the slug is unknown. Supports limit/offset pagination, excludeEventId for de-duplicating already-seen events, and optional ty
- List Featured Tags
List featured Polymarket US tag sections from the public gateway API. Featured tags are curated browse sections, often with subtags, intended for discovery UI and recommendation flows rather than exhaustive filtering. Use List Tags when the
- List Leagues
List current Polymarket US sports leagues from the v2 public gateway API. This is the preferred action for discovering league slugs such as "nfl" or "nba" before calling Get League By Slug or List Events For League. Supports limit/offset pa
- List Markets
Discover Polymarket US markets from the public gateway API. Use this action when an agent needs candidate market slugs or IDs before reading market details, order books, best bid/offer, or preparing orders. Practical guidance for agents: -
- List Series
List Polymarket US series from the public gateway API. Series are recurring or grouped event collections, such as seasonal or repeated sports event groupings. Use this action to discover a series ID or slug before fetching related events or
- List Sports
List Polymarket US sports from the current v2 public gateway API. Use this for sports browsing and for discovering sport slugs such as "football" or "basketball" before calling Get Sport By Slug or List Events For Sport. This action does no
- List Sports Teams
List Polymarket US sports teams from the legacy v1 public gateway API. Use this action when an agent needs team metadata for sports events or needs to filter teams by league, name, abbreviation, or Polymarket team ID. The Pydantic filter fi
- List Sports Teams For Provider
List Polymarket US legacy v1 sports team mappings for a data provider. Use this action when an agent needs provider-specific team IDs for SportsDataIO or Sportradar integrations. Pass provider as the enum value "PROVIDER_SPORTSDATAIO" or "P
- List Subjects
List Polymarket US subject entities from the public gateway API. Subjects are teams, people, candidates, players, nominees, or other named entities that markets can be about. Use this action to discover the subject ID or slug before calling
- List Tags
List ranked Polymarket US tags from the public gateway API. Tags are topic, sport, league, and browse filters that agents can use to narrow event or market discovery before calling event and market listing tools. Use parentSlug="sports" to
- Modify Multiple Orders
Modify up to 20 Polymarket US open orders in one request. Use only when the user explicitly asks to change the batch. These live cancel-replace style mutations can change funding requirements, exposure, maker-only behavior, queue priority,
- Modify Order
Modify one existing Polymarket US open order. This is a live cancel-replace style mutation and should only be used when the user explicitly asks to change an order. It can alter exposure, required funds, queue priority, and fill behavior; v
- Preview Order
Preview a Polymarket US order without submitting it to the market. Use this signed, read-only action before live order creation to validate parameters and inspect the calculated order response. It requires Polymarket US signed authenticatio
- Search Markets And Events
Search public Polymarket US markets and events for discovery. Use this for natural-language discovery when an agent needs candidate market or event slugs/IDs before calling specific market/event endpoints. Search results should not be treat
Setup
Setup guide
- 11. In Switchy, open the Integrations panel and search for Polymarket US. 2. Click Connect and you'll be prompted to paste your Polymarket API key. 3. Log into your Polymarket US account, navigate to Settings → API Keys, and generate a new key with trading permissions. 4. Copy the key and paste it into Switchy's auth dialog, then click Authorize. 5. Switchy confirms the connection and shows Polymarket US as active. 6. Open any Space, type '@Polymarket US get account balances' and send — if you see your buying power and open positions, the integration works. 7. From now on, @mention Polymarket US in any message to preview orders, place trades, cancel positions, or pull activity history.
What teammates see: by default, memories from Polymarket US are scoped to the Space (PROJECT visibility) - you can mark any memory PRIVATE or share it ORG-wide.
Works well with
Top models
Compatibility data appears once enough Spaces have used this MCP together with a given model.
How Switchy teams use it
Starter prompts
Check Account Status
@Polymarket US show my account balances and any funds currently reserved by open orders.Open in a Space →
Preview Market Order
@Polymarket US preview a $500 buy order on 'Yes' for the 2024 election market and show me the expected fill price.Open in a Space →
Cancel All Open Orders
@Polymarket US cancel all my open orders across every market.Open in a Space →
Close Existing Position
@Polymarket US close my position in the Fed rate decision market by selling all my 'Yes' shares at market price.Open in a Space →
Review Recent Activity
@Polymarket US get my recent portfolio activities including trades, deposits, and any resolved markets from the past week.Open in a Space →
Example outputs
Illustrative - representative of the model's voice and quality, not literal recordings.
@Polymarket US what's my current buying power and how much do I have tied up in open orders right now?
Your Polymarket US account shows $2,847.32 in available buying power. You have $1,205.50 reserved across 7 open limit orders. Your total balance is $4,052.82, with no pending deposits or withdrawals. All figures are in USDC. This snapshot reflects your account state as of now; fills or cancellations will update these numbers immediately.
This example uses the read-only Get Account Balances tool to show liquidity before trading. Requires API_KEY authentication. The MCP returns real-time balances but cannot predict imminent fills or market moves that might change your exposure seconds later.
@Polymarket US place a $50 YES order at 62¢ on the 'Fed cuts rates in March' market, and show me the preview first.
Preview for 'Fed cuts rates in March': Buying 80.65 YES shares at 62¢ limit costs $50.00 (including estimated fees of ~$0.40). Your order will sit on the book until filled or cancelled. If filled, you profit $30.25 if the market resolves YES, lose $50 if NO. Buying power required: $50.00. Reply 'confirm' to submit this live order to Polymarket US.
This example chains Preview Order (read-only) with Create Order (write). The preview step is critical—Polymarket orders execute immediately if liquidity exists, and cancellations don't undo fills. Always preview before committing real funds. The MCP enforces explicit confirmation for destructive mutations.
@Polymarket US review my last 15 trades and tell me which markets I'm most active in and whether I'm net profitable this month.
Your last 15 Polymarket US trades span 8 markets. You've traded 'Presidential Election 2024' six times (net +$34.12), 'Fed Rate Decision March' four times (net −$18.50), and 'Unemployment Rate Above 4%' twice (net +$9.00). Across all trades this month, you're up $47.89 after fees. Three markets remain unresolved, so final P&L will shift when those settle. This analysis uses your activity feed; it doesn't account for unrealized gains in open positions.
This example uses Get Activities to fetch trade history, then applies AI reasoning to summarize patterns and calculate net P&L. The MCP provides raw activity data; the AI interprets it. Unresolved markets mean the final profit picture is incomplete until settlement.
Use-case deep-dives
When real-time order management beats spreadsheet tracking
A 3-person research team runs a live trading desk on election night, placing conditional orders across 15 swing-state markets as precinct data rolls in. The Cancel All Open Orders and Create Multiple Orders tools let them pivot the entire book in under 30 seconds when a key county flips. This MCP wins when speed matters more than audit trails—you're reacting to live events, not building compliance reports. The 20-order batch limit means you'll still need two calls for a full 30-market sweep, but that's faster than toggling browser tabs. If your team trades fewer than 5 markets or places orders once a day, the Polymarket web UI is simpler. Use this MCP when you're managing 10+ concurrent positions and need programmatic cancel-and-replace during volatile windows.
Close Position Order automates exit math for multi-market books
A solo analyst holds 22 open positions across tech IPO and macro markets and wants to flatten exposure before month-end reporting. The Close Position Order tool calculates the exact opposite-side quantity to zero out each position, then submits the order in one call. This beats manual math when you're closing more than 3 positions—the tool reads your current holdings from Get Account Balances and sizes the exit trade automatically. The trade-off: if liquidity is thin, you might leave a residual 2-share stub that requires a second order. For teams closing fewer than 3 positions a week, the Polymarket UI's one-click close is faster. This MCP pays off when you're systematically unwinding 10+ positions and want to script the entire exit sequence without spreadsheet risk.
Get Activities pulls transaction logs for internal review
A 5-person fund needs to document all Polymarket trades, deposits, and withdrawals for a quarterly compliance check. The Get Activities tool returns a structured feed of every account event—trades, resolutions, referral credits—filtered by date range and activity type. This MCP is the right call when you're exporting data for a third-party auditor or internal risk review, not when you're casually checking yesterday's fills. The tool requires API key auth, so you'll need to rotate keys if the compliance officer isn't the same person who trades. If your team places fewer than 50 trades a quarter, downloading CSV from the Polymarket dashboard is less setup. Use this MCP when you're pulling 100+ activity records or need to automate monthly reconciliation against your accounting system.
Frequently asked
What does the Polymarket US MCP let me do in Switchy?
It connects your Polymarket US account so you can place and cancel prediction-market orders, check balances, close positions, and review trade history—all from Switchy's chat interface. You're trading real money on live markets, so every Create Order or Cancel Order call executes immediately. Use it when you want to manage positions without switching tabs or when you need to batch-cancel orders across multiple markets.
Do I need a Polymarket US API key to connect this MCP?
Yes. The MCP uses API_KEY authentication, which means you generate a key in your Polymarket US account settings and paste it into Switchy. That key grants full trading permissions—Switchy can place orders, cancel them, and withdraw funds on your behalf. Treat it like a password. If your team shares one Switchy workspace, only connect the key for the account you want everyone to trade from.
Can the MCP preview an order before I place it?
Yes. The toolset includes a Preview Order action that shows expected fill price, fees, and position impact without committing funds. Always preview first unless you've already reviewed the exact parameters—Create Order executes live and can fill instantly or reserve buying power. The MCP won't stop you from placing a bad trade, so use the preview to sanity-check size and direction.
How is this different from trading on Polymarket's website?
The MCP lets you script trades, batch-cancel orders, and pull account data into Switchy prompts—useful if you're building a trading bot or want to cross-reference market data with other tools. The website is faster for one-off trades and shows richer charts. If you just want to bet on a few markets manually, stay in the browser; if you're automating or need to cancel fifty orders at once, use the MCP.
Who on my team should connect the Polymarket US MCP?
Whoever owns the trading account and is comfortable giving Switchy full order-execution access. Because the MCP uses a single API key, everyone in the workspace trades from the same Polymarket account—there's no per-user permission model. If you want separate accounts, each person needs their own Switchy workspace. And remember: every Create Order call spends real money, so only connect it in workspaces you trust.