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

# Leads

> Purchases that pay at least $1 in every outcome a relation allows.

A **lead** is a two-leg purchase that, because of a proven relation, pays at least $1 whatever happens. When the two legs cost less than $1 together, the difference is the edge.

For example, if "49ers over 10.5 points" implies "49ers over 3.5 points", then buying **No** on the first and **Yes** on the second pays \$1 in every score:

| 49ers score | No on over 10.5 | Yes on over 3.5 | Pays |
| ----------- | --------------- | --------------- | ---- |
| 0 – 3       | \$1             | \$0             | \$1  |
| 4 – 10      | \$1             | \$1             | \$2  |
| 11 +        | \$0             | \$1             | \$1  |

At 5¢ and 90¢ the pair costs 95¢ for a guaranteed \$1.

## What a lead reports

```bash theme={null}
curl "https://api.routeur.app/v1/opportunities?executable=true&cross_venue=true" \
  -H "X-API-Key: $ROUTEUR_API_KEY"
```

| Field               | Meaning                                                                                |
| ------------------- | -------------------------------------------------------------------------------------- |
| `legs`              | The two contracts to buy, with venue, side and ask.                                    |
| `cost_usd`          | What the legs cost together, per pair.                                                 |
| `gross_edge_usd`    | \$1 minus the cost.                                                                    |
| `estimated_fee_usd` | Fees estimated from each venue's fee schedule.                                         |
| `net_edge_usd`      | Gross edge minus fees.                                                                 |
| `depth`             | For the best leads each run, both order books walked with real fees and minimum sizes. |

<Warning>
  Only leads with `depth.executable` could be filled at a profit when the books were read. Everything else is priced from top-of-book asks and may be too thin to fill. Leads are observations, not quotes: prices move between the run and your order.
</Warning>

To be told when a lead becomes executable, subscribe to the [`lead.executable` webhook](/webhooks/overview).