# `MPP.Methods.Tempo.HostedFeePayer`
[🔗](https://github.com/ZenHive/mpp/blob/v0.10.0/lib/mpp/methods/tempo/hosted_fee_payer.ex#L1)

Hosted Tempo fee-payer JSON-RPC fill support.

This module sends a client-signed sponsorship envelope to a configured
`eth_fillTransaction` endpoint and locally rebuilds the broadcastable 0x76
transaction from the returned fee token and fee-payer signature.

# `build_fill_request`

```elixir
@spec build_fill_request(Onchain.Tempo.Transaction.t()) ::
  {:ok, map()} | {:error, String.t()}
```

Build the `eth_fillTransaction` request map for a client-signed sponsorship envelope.

# `fill`

```elixir
@spec fill(Onchain.Tempo.Transaction.t(), String.t(), keyword()) ::
  {:ok, Onchain.Tempo.Transaction.t()} | {:error, String.t()}
```

Co-signs a client transaction via a hosted `eth_fillTransaction` endpoint.

Returns `{:ok, tx}` with updated `raw` hex, or `{:error, reason}`.

---

*Consult [api-reference.md](api-reference.md) for complete listing*