> ## Documentation index
> Fetch the complete documentation index at: https://docs.predictefy.com/llms.txt
> Use it to discover every available page before exploring further.

# Market relationships

> Verified subset/superset edges and indicative hedge candidates — including what each one deliberately does not claim.

Two router-only verbs describe how markets relate to one another. Both are deliberately
narrow, and the limits are the important part of this page.

| Verb                  | Returns                                       | Claim strength                                |
| --------------------- | --------------------------------------------- | --------------------------------------------- |
| `fetchRelatedMarkets` | Verified subset/superset outcome implications | Strong — each edge was verified               |
| `fetchHedges`         | Hedge **candidates** for one market           | Indicative — a starting point, not a position |

Both resolve a single anchor market by `marketId` or `slug`, and both are available on
`router` only. Calling either on a venue segment returns an error rather than a partial
answer, because the relationship is cross-venue by definition.

## Related markets

```sh
curl -s "$PREDICTEFY_API_URL/api/router/fetchRelatedMarkets?marketId=MARKET_ID&limit=20" \
  -H "Authorization: Bearer pk_live_YOUR_KEY"
```

An edge means one market's outcome **implies** another's: a subset or superset
relationship, verified before it was stored. "Will inflation exceed 4%?" is a superset of
"Will inflation exceed 5%?" — the second implies the first.

What it deliberately excludes:

- **Same-event siblings are not relations.** Two candidates in one election are not a
  subset or superset of each other, and are not upgraded into a relation claim. Use
  [`fetchEvents`](/guides/events-series/) for siblings.
- **Similarity is not implication.** Markets that merely read alike are matched into
  [clusters](/guides/cross-venue/), which is a different and weaker statement.

Coverage is bounded by what has been verified rather than by what exists. A market with no
edges returns an empty list — that means no verified relationship was found, not that none
could exist.

## Hedges

```sh
curl -s "$PREDICTEFY_API_URL/api/router/fetchHedges?marketId=MARKET_ID&limit=10" \
  -H "Authorization: Bearer pk_live_YOUR_KEY"
```

:::caution[Support is limited, and the response says so]
`fetchHedges` currently returns **same-proposition cross-venue co-members** — markets
matched as the same underlying question on a different venue, where holding the opposite
side is a plausible offset. It does not yet apply the subset/superset filtering a full hedge
surface would need. Those typed relations do exist — the matcher produces verified directional
`subset`/`superset` edges, and `fetchRelatedMarkets` above serves them — but `fetchHedges` reads
cluster co-membership only and never consults them. This is an honest subset, not the finished
feature.
:::

A hedge candidate is **not** a hedge. Predictefy has not checked that the two markets
resolve on equivalent criteria, that there is depth at the size you want, or that fees and
gas leave the offset intact. Those are the same gates that separate an indicative price
discrepancy from arbitrage — see [Cross-venue data](/guides/cross-venue/).

Treat the response as a shortlist to evaluate, and do the resolution-equivalence check
yourself before putting capital behind it.

## Costs

Both are cross-venue reads. See [Credits & billing](/guides/credits/) for the current
weights; they are priced above catalog reads because each one walks stored relationship
data rather than a single venue's catalog.