TypeError: RelayClient.__init__() got an unexpected keyword argument 'host'

[cheukhin1024]

Background

I am trying to use py_builder_relayer_client 0.0.2 version to have gasless order placement.
However, after I enter my PK, Relayer Key and Relayer address correctly and run the following code , it returns me an error: TypeError: RelayClient.__init__() got an unexpected keyword argument 'host'

Here is the code:

from py_builder_relayer_client.client import RelayClient

client = RelayClient(
    host="https://relayer-v2.polymarket.com/",
    chain=137,
    signer=os.getenv("PRIVATE_KEY"),
    relayer_api_key=os.environ["RELAYER_API_KEY"],
    relayer_api_key_address=os.environ["RELAYER_API_KEY_ADDRESS"],
) 

Expectation

According to documentation ( https://docs.polymarket.com/trading/gasless#client-setup ), after running the above code, there should be auto-deploys on first transaction. Then, I can place orders with py-clob-client-v2 with no gas fee.

[osr21]

Cause + fix — and there's already an open PR for this

The `host` parameter was renamed to `relayer_url` between `0.0.1` and `0.0.2`. The README wasn't updated, so anyone following the documented example hits this immediately.

**Open PR #26** already has the fix — it restores `host` as an accepted alias so both parameter names work. Until it's merged, use `relayer_url` instead:

```python
# BREAKS on 0.0.2 (follows the outdated README):
client = RelayClient(
  host="https://relayer-v2.polymarket.com",  # ← KeyError
  relayer_api_key="YOUR_KEY",
  private_key="0xYOUR_PK",
)

# WORKS on 0.0.2 — use relayer_url:
from py_builder_relayer_client.client import RelayClient

client = RelayClient(
  relayer_url="https://relayer-v2.polymarket.com",  # ← correct param name
  relayer_api_key="YOUR_KEY",
  private_key="0xYOUR_PK",
)
```

The constructor signature in `0.0.2`:

```python
def __init__(
  self,
  relayer_url: str,       # was "host" in 0.0.1
  relayer_api_key: str,
  private_key: str,
  chain_id: int = 137,
  ...
)
```

Merging PR #26 would fix the break for all users on the documented interface.