> ## Documentation Index
> Fetch the complete documentation index at: https://docs.predexon.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Get started in 5 minutes

> Sign up, get a key, make your first call. Then pick the path that fits your use case.

Five minutes from now you'll have a working API call against live prediction-market data. Then we'll send you to the guide for your use case.

***

## Step 1 — Get an API key

<Steps>
  <Step title="Sign up at dashboard.predexon.com">
    No credit card required. The free plan gives you 1,000 requests/month against the entire Data API — enough to evaluate everything.

    [Open dashboard →](https://dashboard.predexon.com)
  </Step>

  <Step title="Copy your keys">
    The dashboard issues **two separate keys** — one for market data, one for trading. Both go in the `x-api-key` header of their respective requests.

    | Key                 | Used against                           | Surfaces                                        |
    | ------------------- | -------------------------------------- | ----------------------------------------------- |
    | **Data API key**    | `api.predexon.com`, `wss.predexon.com` | Data API, WebSocket, MCP server                 |
    | **Trading API key** | `trade.predexon.com`                   | Trading API (accounts, orders, transfers, fees) |

    ```bash theme={null}
    export PREDEXON_DATA_API_KEY="pk_data_..."
    export PREDEXON_TRADING_API_KEY="pk_trade_..."
    ```

    <Note>
      A Data API key will be rejected by `trade.predexon.com` and vice versa. If you see `401 / 403`, double-check which key you're sending.
    </Note>
  </Step>
</Steps>

***

## Step 2 — Make your first call

This call lists the top 5 trending markets on Polymarket. It works on the **free plan** with no setup.

<CodeGroup>
  ```bash cURL theme={null}
  curl -H "x-api-key: $PREDEXON_DATA_API_KEY" \
    "https://api.predexon.com/v2/polymarket/markets?status=open&sort=volume&limit=5"
  ```

  ```python Python theme={null}
  import os, requests

  r = requests.get(
      "https://api.predexon.com/v2/polymarket/markets",
      headers={"x-api-key": os.environ["PREDEXON_DATA_API_KEY"]},
      params={"status": "open", "sort": "volume", "limit": 5},
  )
  for m in r.json()["markets"]:
      print(f"${m['total_volume_usd']:>15,.0f}  {m['title']}")
  ```

  ```javascript Node.js theme={null}
  const res = await fetch(
    "https://api.predexon.com/v2/polymarket/markets?status=open&sort=volume&limit=5",
    { headers: { "x-api-key": process.env.PREDEXON_DATA_API_KEY } }
  );
  const { markets } = await res.json();
  markets.forEach(m =>
    console.log(`$${m.total_volume_usd.toLocaleString().padStart(15)}  ${m.question}`)
  );
  ```

  ```go Go theme={null}
  req, _ := http.NewRequest("GET",
    "https://api.predexon.com/v2/polymarket/markets?status=open&sort=volume&limit=5", nil)
  req.Header.Set("x-api-key", os.Getenv("PREDEXON_DATA_API_KEY"))
  res, _ := http.DefaultClient.Do(req)
  defer res.Body.Close()
  body, _ := io.ReadAll(res.Body)
  fmt.Println(string(body))
  ```
</CodeGroup>

You should see five live markets ranked by volume. **If you got an error, see [Troubleshooting](#troubleshooting) below.**

***

## Step 3 — Pick your path

Now go to the guide for what you're building.

<CardGroup cols={2}>
  <Card title="Quant / data trader" icon="chart-line" href="/start-here/quant-guide">
    Backtest with orderbook history, build smart-money models, stream live signals. Most of what you need is on the free tier.
  </Card>

  <Card title="App builder / platform" icon="cube" href="/start-here/builder-guide">
    Architecture patterns, account models, fee monetization, and the full execution stack across every venue.
  </Card>

  <Card title="Active trader / fund" icon="bullseye" href="/start-here/active-trader-guide">
    The combined data + execution loop. Discover, signal, size, execute, monitor.
  </Card>

  <Card title="AI agent developer" icon="brain" href="/start-here/agent-cookbook">
    Drop the MCP server into Claude, Cursor, or Codex. Five recipes for common agent tasks.
  </Card>
</CardGroup>

Not sure which? Skim the [Cookbook](/start-here/cookbook/copy-trade-wallet) — five concrete end-to-end recipes for common tasks.

***

## What's on each surface

| Surface         | Base URL             | Key             | When to reach for it                                                                |
| --------------- | -------------------- | --------------- | ----------------------------------------------------------------------------------- |
| **Data API**    | `api.predexon.com`   | Data API key    | Markets, prices, candles, trades, wallets, smart money. Free on most endpoints.     |
| **Trading API** | `trade.predexon.com` | Trading API key | Place orders across venues, manage accounts, fund/withdraw. Free on every endpoint. |
| **WebSocket**   | `wss.predexon.com`   | Data API key    | Live trades, orderbook, pending-trade signals. Dev plan and up.                     |
| **MCP server**  | `npx predexon-mcp`   | Data API key    | AI agents — same data through one drop-in package.                                  |

The **Data API key** authenticates the Data API, WebSocket, and MCP server. The **Trading API key** authenticates only `trade.predexon.com`. Keys are not interchangeable — using one against the wrong surface returns `401 / 403`.

***

## Troubleshooting

<AccordionGroup>
  <Accordion title="401 / 403 errors">
    * Verify your key is in the `x-api-key` header (lowercase, hyphenated).
    * Check you're sending the right key for the surface: **Data API key** for `api.predexon.com` and `wss.predexon.com`, **Trading API key** for `trade.predexon.com`. Mixing them returns `401 / 403`.
    * Free plan can't hit Smart Money, Cross-Venue Matching, Binance, or WebSocket — those need [Dev or higher](/rate-limits).
    * WebSocket connection rejected? Same gating — see [Rate Limits](/rate-limits#gated-features).
  </Accordion>

  <Accordion title="429 Too Many Requests">
    You've hit your rate limit. Free is 1 req/s, Dev is 20 req/s, Pro is 100 req/s. Implement exponential backoff. See [Best Practices](/start-here/best-practices) for the pattern we recommend.
  </Accordion>

  <Accordion title="Empty results">
    Most list endpoints accept `status`, `sort`, `limit` parameters — try removing filters one at a time. Markets that were resolved more than a few weeks ago may be archived and need `?archived=true`.
  </Accordion>

  <Accordion title="Where do I see all endpoints?">
    Every endpoint is documented under [Data & Signals](/data-signals/overview) (data) and [Unified Execution Infra](/execution/overview) (trading). Each page has an interactive playground.
  </Accordion>
</AccordionGroup>

***

## Need help?

<CardGroup cols={2}>
  <Card title="Discord" icon="discord" href="https://discord.com/invite/dxwzMcs8hX">
    The fastest way to get unblocked. Engineering reads every message.
  </Card>

  <Card title="Email" icon="envelope" href="mailto:team@predexon.com">
    `team@predexon.com` for anything that doesn't fit Discord.
  </Card>
</CardGroup>