# Bridge coverage · API reference · Femtos

> Every HyperCore ↔ HyperEVM leg since our data starts, paired with its other leg: matched share per direction and token, why the others are not, latency. GET /v1/bridges/coverage on HyperCore and HyperEVM: parameters, response fields and a live call per layer.

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  (https://femtos.xyz/agents.md#agent-onboarding)
- Decimals are exact strings, times Unix milliseconds, addresses lowercase `0x`
- Whole API in one file: https://femtos.xyz/agents.md · OpenAPI: https://api.femtos.xyz/v1/openapi.json · Index: https://femtos.xyz/llms.txt
- Page with live calls: https://femtos.xyz/reference/bridge-coverage

## Bridge coverage — GET `/v1/bridges/coverage`

Every HyperCore ↔ HyperEVM leg since our data starts, paired with its other leg: matched share per direction and token, why the others are not, latency.

Layers: HyperCore, HyperEVM. Not on Elysium: covers the HyperCore <> HyperEVM legs; the HyperEVM <> Elysium ones are in GET /v1/bridges?route=evm_elysium, with no coverage report until the Elysium token registry runs (Kinetiq factories not deployed yet).
Page with live calls: https://femtos.xyz/reference/bridge-coverage?layer=<hypercore|hyperevm>

| Param | In | Example or values | Meaning |
|---|---|---|---|
| `window` | query | `all`, `30d`, `7d`, `24h` | Legs of the window (by sending time) |

HyperCore, HyperEVM:

```bash
curl -H "Authorization: Bearer $FEMTOS_KEY" "https://api.femtos.xyz/v1/bridges/coverage?window=all"
```

| Field | Type | Meaning |
|---|---|---|
| `directions.evm_to_core` | object | {legs, matched, coverage, unmatched, notALeg, finalPending, reverted, matchedBy, latencyMs, unpairedCredits, tokens} |
| `directions.core_to_evm` | object | {legs, matched, coverage, unmatched, notALeg, finalPending, reverted, matchedBy, latencyMs, unpairedCredits, tokens} |
| `directions.evm_to_core.coverage` | number \| null | matched / (legs - notALeg - in_flight): 1 = every settled leg has its other leg |
| `directions.evm_to_core.unmatched` | object | {<reason>: n}. in_flight: younger than the other layer read (2 min; 30 s for core_to_evm); missing_peer: no credit found; amount_mismatch: a credit of the same system address to the same account, another amount; late_peer (core_to_evm): an identical credit 10 s-10 min later, past the 10 s window; unknown_token: system address not in the token registry; unmatched: views source (no reason) |
| `directions.core_to_evm.matchedBy` | object | core_to_evm: {nonce, order} |
| `directions.evm_to_core.unpairedCredits` | object \| null | {in_flight, missing_peer}: credits on the receiving side no leg took (null: views source) |
| `source` | materialized \| views | materialized: the tables bridge-match keeps (a reason per leg); views: the matching views read directly (every 10 min) |
| `settledUntil` | int \| null | materialized: every leg before this time was matched with both layers read past it (Unix ms) |

## Related (Bridges & wallets)

- [Cross-layer wallet](https://femtos.xyz/reference/wallet.md) `GET /v1/wallet/{address}`: One address (or a named wallet's handle) on HyperCore, HyperEVM and Elysium, plus its latest events. (Elysium, HyperCore, HyperEVM)
- [Wallet stream](https://femtos.xyz/reference/ws/wallet.md) `WS wallet`: Every event of the three layers touching one address. (Elysium, HyperCore, HyperEVM)
- [Swaps by wallet](https://femtos.xyz/reference/wallet-trades.md) `GET /v1/trades`: Every swap a wallet sent (or a pool’s, a token’s), newest first, filterable by token, side, size and time. (Elysium, HyperEVM)
- [Transfers by wallet](https://femtos.xyz/reference/wallet-transfers.md) `GET /v1/transfers`: ERC-20 transfers sent and received by a wallet, newest first, filterable by token, direction, size and time. (Elysium, HyperEVM)
- [Ledger stream](https://femtos.xyz/reference/ws/ledger.md) `WS hc.ledger`: Deposits, withdrawals, transfers and other non-trade balance moves. (HyperCore)
- [Bridge movements](https://femtos.xyz/reference/bridge.md) `GET /v1/bridges`: Matched HyperCore ↔ HyperEVM transfers with 24 h stats. (Elysium, HyperCore, HyperEVM)
- [Bridge stream](https://femtos.xyz/reference/ws/bridge.md) `WS elysium.bridge · bridge.transfers`: Each HyperCore ↔ HyperEVM transfer, initiated then completed. (Elysium, HyperCore, HyperEVM)

Every page: https://femtos.xyz/reference.md