# Task: fix a credential-leak bug in this code

This directory is a slice of the `hermes-agent` codebase (the modules involved in
building the Anthropic-protocol HTTP client). There is a security bug in it, described
below. Fix it by editing the source. A regression test is included.

## The bug

When a custom provider is configured with `api_mode: anthropic` and its own API key,
Hermes sends **two** credentials to the provider's endpoint:

- `x-api-key: <the configured provider key>` — correct
- `Authorization: Bearer <ANTHROPIC_AUTH_TOKEN from the environment>` — **leak**

Any `ANTHROPIC_AUTH_TOKEN` present in the shell — commonly pointing at a completely
unrelated account or proxy — is transmitted to the third-party endpoint on every
request. This is both a security leak (one vendor's credential sent to another vendor's
server) and a functional failure (the receiving endpoint rejects the unexpected token).

## Root cause

`agent/anthropic_adapter.py::build_anthropic_client` passes `api_key=<provider key>`
but never suppresses the Anthropic SDK's environment fallback. The SDK auto-reads
`ANTHROPIC_AUTH_TOKEN` when `auth_token` is not set and attaches it as a `Bearer`
header **in addition to** `x-api-key`.

Note: passing `auth_token=None` does **not** fix it — the SDK treats `None` as
"fall back to env". The env-sourced token must be actively suppressed on the client.

## What to do

1. Edit the source in this directory to stop the foreign credential from being sent to
   a third-party endpoint, while keeping the provider's own `x-api-key` intact. Official
   Anthropic OAuth flows (which set `auth_token` explicitly) must keep working.
2. **Do not modify `regression_test.py`.** It is the acceptance criterion.
3. Verify with: `./run_test.sh` — it must print `OK`.

The test lives in `regression_test.py` and is run with `PYTHONPATH=. python regression_test.py`.