Assymetrix

io.github.assymetrixPublished by GitHub account assymetrixv0.1.1Updated Oct 29, 2026

Read-only prediction market data (Polymarket, Kalshi, Limitless) from the Assymetrix Data API.

VerifiedSTDIODesktop onlyFinanceData & Analytics

Overview

AI-generated overview

Read-only prediction market data from Polymarket, Kalshi and Limitless, letting an assistant search markets and inspect odds, prices and history.

What you can do
  • Search markets by question text, sorted by 24-hour volume, with venue, last price, bid and ask, and end date
  • Read one market's current odds: last price, bid, ask, spread, price changes, per-outcome price, volume and liquidity
  • Fetch OHLCV candles for a time range or the market's trades, newest first
When to use it
Useful when you want an assistant to look up prediction market questions and their implied probabilities across Polymarket, Kalshi and Limitless, for research or comparison, without any trading capability.
Requirements
Runs locally over stdio, typically via npx from the npm package, so Node.js is needed. Requires an Assymetrix API key in the ASSYMETRIX_API_KEY environment variable; a free key works and is created from an Assymetrix account. Network access to the Assymetrix Data API. Optional settings cover API base URL, timeout and log level.
Before you install
The API key is a secret sent in the x-api-key header; keep it in an environment variable or the client's secure store rather than in a config file or chat. The free plan is limited to 10,000 requests per rolling 30 days, one request per second and 30 days of history, and each tool call counts as one request; paid plans exist. Market data goes to the Assymetrix Data API. The server is read-only and does not place orders or move money, and its output is not financial advice.

Installation

In SourceWeft

  1. Open Assymetrix in the dashboard and add it to a workspace.
  2. Enable the server for the chats that should use its tools.

Desktop only via STDIO. STDIO servers start a local process, so they need the SourceWeft desktop host.

Other MCP clients

Follow the launch instructions in the repository.

README

Assymetrix agent tools

Prediction market data from Polymarket, Kalshi and Limitless for AI agents, from the Assymetrix Data API:

Everything here only reads market data. Nothing places orders, moves money or links wallets, and nothing here is financial advice. You use your own Assymetrix API key, and a free key works.

Get an API key

  1. Create a free account at https://dashboard.assymetrix.com/signup?utm_source=github&utm_campaign=agent-tools
  2. Open API Keys and create a key. It is shown once and starts with asy_.
  3. Keep it in an environment variable, for example in your shell profile: export ASSYMETRIX_API_KEY=asy_...

The Free plan includes 10,000 requests per rolling 30 days, 1 request per second and 30 days of history. Each tool call is one request. Paid plans: https://dashboard.assymetrix.com/billing

Install

Recommended: the Claude Code plugin (MCP server and skill)

text
/plugin marketplace add assymetrix/assymetrix-agent-tools/plugin install assymetrix@assymetrix

Claude Code asks for your API key when you enable the plugin and keeps it in your system's secure store, so the key never sits in a config file or the chat.

Other clients

These read the key from an environment variable or their own config file. Keep the key in your shell profile (export ASSYMETRIX_API_KEY=asy_...) rather than typing it into a command.

Claude Code without the plugin (--transport goes before the name):

bash
claude mcp add --env ASSYMETRIX_API_KEY="$ASSYMETRIX_API_KEY" --transport stdio assymetrix -- npx -y @assymetrix/mcp-server

Codex:

bash
codex mcp add assymetrix --env ASSYMETRIX_API_KEY="$ASSYMETRIX_API_KEY" -- npx -y @assymetrix/mcp-server

Cursor (~/.cursor/mcp.json or .cursor/mcp.json):

json
{  "mcpServers": {    "assymetrix": {      "command": "npx",      "args": ["-y", "@assymetrix/mcp-server"],      "env": { "ASSYMETRIX_API_KEY": "${env:ASSYMETRIX_API_KEY}" }    }  }}

Claude Desktop (claude_desktop_config.json):

json
{  "mcpServers": {    "assymetrix": {      "command": "npx",      "args": ["-y", "@assymetrix/mcp-server"],      "env": { "ASSYMETRIX_API_KEY": "asy_..." }    }  }}

VS Code (.vscode/mcp.json, which asks for the key and hides it):

json
{  "inputs": [    {      "type": "promptString",      "id": "assymetrix-key",      "description": "Assymetrix API key",      "password": true    }  ],  "servers": {    "assymetrix": {      "type": "stdio",      "command": "npx",      "args": ["-y", "@assymetrix/mcp-server"],      "env": { "ASSYMETRIX_API_KEY": "${input:assymetrix-key}" }    }  }}

Skill only (Claude Code, Codex, Cursor and other agents)

bash
npx skills add assymetrix/assymetrix-agent-tools

The skill reads ASSYMETRIX_API_KEY from the agent's environment and never prints it.

Tools

ToolWhat it returns
search_marketsMarkets whose question contains your text, sorted by 24-hour volume: id, venue, last price, best bid and ask, end date.
get_market_pricesOne market's current odds: last price, bid, ask, spread, price changes, each outcome's price, volume and liquidity.
get_market_historyOHLCV candles for a time range (the interval is picked to fit), or the market's trades, newest first.

Prices are probabilities from 0 to 1. How far back history goes depends on your plan; when your plan cuts a range, the result says so.

Configuration

VariableDefaultMeaning
ASSYMETRIX_API_KEYnoneYour API key. Without it the server starts and explains how to get one.
ASSYMETRIX_API_BASE_URLhttps://api.assymetrix.com/api/v1Only for testing. Must be https (plain http only for localhost).
ASSYMETRIX_TIMEOUT_MS15000Timeout for one API request, 1000 to 60000.
ASSYMETRIX_LOG_LEVELwarnerror, warn, info or debug. Logs go to stderr.

Privacy

  • The MCP server talks only to the Assymetrix Data API, sending your key in the x-api-key header, a User-Agent with its version, and a random request id that support can use to find a call.
  • It collects no telemetry, writes nothing to disk, and never logs or returns your key.
  • The skill runs curl against the same API from your own machine.
  • Privacy policy: https://www.assymetrix.com/privacy-policy. Support: [email protected].

Development

bash
cd packages/mcp-serverpnpm installpnpm run check      # type check, build, then the tests (no network)node ../../skills/validate-skill.cjs ../../skills/prediction-market-data            # skill format checksnode ../../skills/validate-skill.cjs ../../skills/prediction-market-data --release  # also fails on open TODO markers

License

MIT

Source: README.md at commit f82e670

Tools

0
SourceWeft has not started this package in its sandbox yet, so its tools are not known.

Version history

1
  1. v0.1.1LatestOct 29, 2026

Score

50% of the applicable checks met

How complete this listing is, computed from the registry entry, the endpoint and public sources. Not a rating of the server and not a statement that it is safe or working today: reachability is a dated check, and no installs or reviews go into the score.

  • Reached in the last 30 days25 pts

    Keep the endpoint answering the MCP handshake; SourceWeft probes it every 30 days.

  • Auth declared10 pts

    Declare the credential headers in the registry entry, or keep the endpoint answering the probe so its auth can be classified.

  • Tools listed15 pts

    Answer tools/list without a credential, or ship a package that starts in a sandbox without one.

  • DescriptionRequired15 pts
  • Logo10 pts
  • Documentation15 pts
  • License10 pts