diff --git a/README.md b/README.md
index ec59054..e5077a2 100644
--- a/README.md
+++ b/README.md
@@ -69,7 +69,9 @@ evalharness eval run gsm8k \
 | `--model NAME` | 服务端模型名（配合 `--api-url`）；或直接给完整 spec：`openai/http://h:8000/v1?qwen3-8b` |
 | `--provider {openai-chat,openai-pool}` | 协议/提供方，默认 `openai-chat`；端点池用 `openai-pool` |
 | `--judge NAME` + `--judge-api-url URL` | LLM-judge 模型（hle / simple_qa / imo 需要）；也可单给完整 spec `--judge openai/http://...?m` |
+| `--api-key KEY` | 显式指定主模型端点的 key（优先于环境变量推断；只进请求头，不写入 spec/报告） |
 | `--judge-provider {openai-chat,openai-pool}` | judge 协议；多 judge 端点负载均衡用 `openai-pool` |
+| `--judge-api-key KEY` | 显式指定 judge 端点的 key |
 | `--profile NAME` | 命名生成参数集（内置 `dp4-nothink`、`qwen3-es-parity`、`t1-short`，或任意 `@register_gen_profile` 名）；优先级：插件默认 < profile 默认 < profile 单 bench 覆盖 < 显式参数 |
 | `--disable-thinking` | 发送 `enable_thinking=false`（Qwen3 类思考模型推荐；带 tools 的请求自动退回模板安全的软开关） |
 | `--textools` | 工具以文本形式随 prompt 下发，而非原生 tool_calls |
@@ -164,6 +166,8 @@ evalharness viz show report.json --style errors            # 失败样本下钻
 API key（含 judge）按端点域名自动从环境变量读取：`api.openai.com`→`OPENAI_API_KEY`、
 `anthropic.com`→`ANTHROPIC_API_KEY`、`dashscope`→`DASHSCOPE_API_KEY`、`bigmodel`→`ZAI_API_KEY`；
 其余域名回退 `OPENAI_API_KEY`。自建端点无鉴权时无需设置。
+同一服务有多个 key 时用 `--api-key` 显式指定（跑两次各用一个 key 即可对比；key 只进请求头，
+不会出现在 spec、报告或日志里）。
 
 ## 内置 benchmark
 
diff --git a/evalharness/cli.py b/evalharness/cli.py
index 5a27a44..c194bf3 100644
--- a/evalharness/cli.py
+++ b/evalharness/cli.py
@@ -308,6 +308,8 @@ def _cmd_eval_run(args) -> int:
                     limit_per_task=args.limit_per_task,
                     checkpoint=args.resume,
                     judge_spec=_compose_judge_spec(args), env=args.env,
+                    api_key=getattr(args, 'api_key', ''),
+                    judge_api_key=getattr(args, 'judge_api_key', ''),
                     gen_profile=getattr(args, 'profile', ''),
                     progress_reporter=progress_reporter,
                     status_callback=status_callback))
@@ -524,6 +526,11 @@ def build_parser() -> argparse.ArgumentParser:
                    help='judge model name with --judge-api-url, or full spec')
     p.add_argument('--judge-api-url', default='',
                    help='judge API base URL when --judge is only the model name')
+    p.add_argument('--api-key', default='',
+                   help='explicit API key for the model endpoint (overrides '
+                        'env-based resolution; never written into reports)')
+    p.add_argument('--judge-api-key', default='',
+                   help='explicit API key for the judge endpoint')
     p.add_argument('--judge-provider', default='openai-chat',
                    help='judge protocol/provider (default openai-chat; '
                         'openai-pool for multi-endpoint judges)')
diff --git a/evalharness/model/pool.py b/evalharness/model/pool.py
index 0d85f13..09af0c8 100644
--- a/evalharness/model/pool.py
+++ b/evalharness/model/pool.py
@@ -245,8 +245,15 @@ class AdaptiveGate:
                 **{f'gate_{k}': v for k, v in self.stats.items()}}
 
 
-def pooled(specs: List[str]) -> PooledAdapter:
-    """['openai/http://127.0.0.1:8123/v1?M', ...] -> PooledAdapter."""
+def pooled(specs: List[str], api_key: str = '') -> PooledAdapter:
+    """['openai/http://127.0.0.1:8123/v1?M', ...] -> PooledAdapter.
+
+    api_key: explicit key applied to EVERY member (two-key setups should
+    build two pools, or use env resolution per host)."""
     from .adapter import resolve_adapter
 
-    return PooledAdapter([resolve_adapter(s) for s in specs])
+    members = [resolve_adapter(s) for s in specs]
+    if api_key:
+        for m in members:
+            m.api_key = api_key
+    return PooledAdapter(members)
diff --git a/evalharness/model/runner.py b/evalharness/model/runner.py
index 1fb04bf..d880ca1 100644
--- a/evalharness/model/runner.py
+++ b/evalharness/model/runner.py
@@ -502,6 +502,8 @@ async def run_eval(
     concurrency: int = 32,
     limit: Optional[int] = None,
     gen_kwargs: Optional[Dict[str, Any]] = None,
+    api_key: str = '',
+    judge_api_key: str = '',
     judge_spec: Optional[str] = None,
     judge: Optional[Any] = None,
     progress: bool = True,
@@ -535,7 +537,7 @@ async def run_eval(
     spec = getattr(dataset, 'spec', None)
     if few_shot_num < 0:
         few_shot_num = (spec.few_shot_num if spec is not None else 0)
-    adapter = _make_adapter(model_spec)
+    adapter = _make_adapter(model_spec, api_key=api_key)
     # reports carry a string model label: pre-built adapter objects need one
     model_spec = model_spec if isinstance(model_spec, str) \
         else (getattr(model_spec, 'model', '') or repr(model_spec))
@@ -650,7 +652,7 @@ async def run_eval(
     if judge is None and judge_spec:
         if status_callback:
             status_callback('loading judge model')
-        judge_adapter = _make_adapter(judge_spec)
+        judge_adapter = _make_adapter(judge_spec, api_key=judge_api_key or api_key)
         judge = _judge_callable(judge_adapter)
 
     if status_callback:
@@ -693,7 +695,7 @@ def _env_user_adapter(spec: str):
 _ENV_USER_CACHE = {}
 
 
-def _make_adapter(spec: str) -> ModelAdapter:
+def _make_adapter(spec: str, api_key: str = '') -> ModelAdapter:
     """Model spec forms:
     - 'mock[:mode]'                     offline adapter
     - 'openai-pool/<base-url-template>?model' with {port} placeholder:
@@ -743,7 +745,7 @@ def _make_adapter(spec: str) -> ModelAdapter:
                     specs.append(f'openai/{u}?{model}')
             elif seg:
                 specs.append(f'openai/{seg}?{model}')
-        adapter = pooled(specs)
+        adapter = pooled(specs, api_key=api_key) if api_key else pooled(specs)
     elif re.fullmatch(r'mock[-:](boxed|oracle|fc|tool|echo|const)?', spec):
         # mock-boxed (preferred) == legacy mock:boxed; bare 'mock' == echo.
         # NEVER reuse the cached singleton: resolve_adapter memoizes and a