diff --git a/src/polygateway/embedding.py b/src/polygateway/embedding.py
index 804d61d..ae47716 100644
--- a/src/polygateway/embedding.py
+++ b/src/polygateway/embedding.py
@@ -41,7 +41,12 @@ from polygateway.middleware.ratelimit import QuotaGate
 from polygateway.middleware.retry import _failure_reason, backoff_delay
 from polygateway.middleware.telemetry import TelemetryEmitter
 from polygateway.sources import SourceCooldownMemo
-from polygateway.types import ChatRequest, EmbeddingResponse, LLMResponse
+from polygateway.types import (
+    ChatRequest,
+    EmbeddingResponse,
+    LLMResponse,
+    strip_unsupported_extra_body,
+)
 
 if TYPE_CHECKING:
     from collections.abc import Awaitable, Callable, Mapping
@@ -111,7 +116,9 @@ class EmbeddingClient:
         if expected_dim is not None and expected_dim < 1:
             raise ValueError("expected_dim 必须 ≥ 1")
         self._scope = scope
-        self._sources = list(sources)
+        # embed payload 硬编码 {model, input},带 extra_body 的源必须先剥离,
+        # 否则遥测会记录一个从未发出的采样参数(issue #4 决策 G)
+        self._sources = strip_unsupported_extra_body(list(sources), path="embedding")
         self._selector = selector
         self._quota = QuotaGate(limiter)
         self._breaker = BreakerGate(breaker)
diff --git a/src/polygateway/ocr.py b/src/polygateway/ocr.py
index 864a7c3..cbbc54d 100644
--- a/src/polygateway/ocr.py
+++ b/src/polygateway/ocr.py
@@ -44,6 +44,7 @@ from polygateway.types import (
     OcrLayoutResult,
     OcrTextResult,
     Usage,
+    strip_unsupported_extra_body,
 )
 
 if TYPE_CHECKING:
@@ -113,7 +114,9 @@ class OcrClient:
         if quota_full not in ("wait", "fail_fast"):
             raise ValueError(f"quota_full 必须是 wait|fail_fast: {quota_full!r}")
         self._scope = scope
-        self._sources = list(sources)
+        # MonkeyOCR 只发 multipart 表单,带 extra_body 的源必须先剥离,否则
+        # 遥测会记录一个从未发出的采样参数(issue #4 决策 G)
+        self._sources = strip_unsupported_extra_body(list(sources), path="OCR")
         self._selector = selector
         self._feed_health = isinstance(selector, OutcomeAwareSelector)
         self._quota = QuotaGate(limiter)
diff --git a/src/polygateway/types.py b/src/polygateway/types.py
index 0aa2326..96f71e5 100644
--- a/src/polygateway/types.py
+++ b/src/polygateway/types.py
@@ -4,12 +4,15 @@
 fake,字段顺序即公共承诺;新增字段只增不删且必带默认值。
 """
 
+import dataclasses
 import json
 from collections.abc import Mapping
 from dataclasses import dataclass, field
 from types import MappingProxyType
 from typing import Any
 
+from loguru import logger
+
 _MISSING_DONE_DOMAIN = frozenset({"retry", "salvage"})
 
 _PROTECTED_OVERLAY_KEYS: Mapping[str, str] = MappingProxyType(
@@ -234,6 +237,34 @@ class SourceConfig:
         object.__setattr__(self, "extra_body", MappingProxyType(validated))
 
 
+def strip_unsupported_extra_body(
+    sources: list[SourceConfig], *, path: str
+) -> list[SourceConfig]:
+    """剥离非 chat 路径不消费的 `extra_body` 并 warning(issue #4 决策 G)。
+
+    剥离是必需的而非顺手清理: embedding 的 payload 硬编码 `{model, input}`、
+    MonkeyOCR 只发 multipart 表单,两者都不会把 `extra_body` 发出去;但遥测的
+    `sampling` 列会并上 `source.extra_body`,不剥离就等于**记录一个从未发出的
+    参数**——那是数据造假,污染的恰是事后复现的唯一依据。
+
+    选择 warning 放行而非报错: 这两条路径本无采样语义,配错的后果远轻于 chat
+    路径,不值得让下游整个装配起不来(2026-07-31 人类拍板)。
+    """
+    stripped = []
+    for source in sources:
+        if source.extra_body:
+            logger.warning(
+                "{} 路径暂不支持 extra_body,源 {} 的该配置已被忽略"
+                "(需要 dimensions 等参数请提 issue): {}",
+                path,
+                source.name,
+                dict(source.extra_body),
+            )
+            source = dataclasses.replace(source, extra_body={})
+        stripped.append(source)
+    return stripped
+
+
 @dataclass(frozen=True)
 class RetryPolicy:
     """重试策略;max_attempts = 总尝试次数(含首次,M1 设计 §2.3 统一语义)。"""
diff --git a/tests/unit/test_embedding.py b/tests/unit/test_embedding.py
index d6c9f95..c95b9b7 100644
--- a/tests/unit/test_embedding.py
+++ b/tests/unit/test_embedding.py
@@ -4,11 +4,13 @@
 VT adapters/embedding.py(归一化);库裁决见设计 §7.3 表。
 """
 
+import contextlib
 import dataclasses
 import json
 
 import httpx
 import pytest
+from loguru import logger
 
 from polygateway.errors import (
     RequestRejectedError,
@@ -350,6 +352,48 @@ class TestEmbedTelemetry:
         assert len(rec.rows[1]["messages"]) < 1000  # 长文本截断后入库
 
 
+@contextlib.contextmanager
+def _captured_warnings():
+    """捕获库发出的 WARNING;loguru 不经标准 logging,pytest 的 caplog 抓不到。"""
+    messages: list[str] = []
+    sink_id = logger.add(messages.append, level="WARNING")
+    try:
+        yield messages
+    finally:
+        logger.remove(sink_id)
+
+
+class TestExtraBodyStripped:
+    """issue #4 决策 G: embedding 路径不消费 extra_body,剥离并 warning。"""
+
+    async def test_stripped_with_warning_but_assembly_succeeds(self):
+        """报错会让下游整个装配起不来,而这条路径本无采样语义(人类拍板)。"""
+        with _captured_warnings() as warnings:
+            client, _ = _embed_client([_src(extra_body={"temperature": 0})], ["ok"])
+        assert client._sources[0].extra_body == {}
+        assert any("extra_body" in m for m in warnings)
+        assert any("dimensions" in m for m in warnings)  # 文案须指路,不能只说不支持
+        await client.embed(["hi"])  # 装配后可正常工作
+
+    async def test_telemetry_never_records_a_parameter_that_was_not_sent(self):
+        """剥离的真正理由: embed payload 硬编码 {model, input},不剥离则审计表
+
+        会显示这次调用带了 temperature=0——那是数据造假,比参数失效更坏。
+        """
+        rec = _MemoryRecorder()
+        client, _ = _embed_client(
+            [_src(extra_body={"temperature": 0})], ["ok"], telemetry=rec
+        )
+        await client.embed(["hi"])
+        assert rec.rows[0]["sampling"] is None
+
+    async def test_no_warning_without_extra_body(self):
+        with _captured_warnings() as warnings:
+            client, _ = _embed_client([_src()], ["ok"])
+        assert client._sources[0].extra_body == {}
+        assert not [m for m in warnings if "extra_body" in m]
+
+
 class TestEmbeddingSettings:
     _ENV = {
         "EMBED__QWEN__1__BASE_URL": "https://gw.example/v1",
diff --git a/tests/unit/test_ocr_client.py b/tests/unit/test_ocr_client.py
index 9d9cc54..ba1f6d9 100644
--- a/tests/unit/test_ocr_client.py
+++ b/tests/unit/test_ocr_client.py
@@ -7,6 +7,7 @@ retry_exhausted/circuit_open/stalled 三组断言即设计 §6 ③ 的 G1 契约
 import asyncio
 
 import pytest
+from loguru import logger
 
 from polygateway.backends.memory.breaker import InMemoryGate
 from polygateway.backends.memory.limiter import InMemoryLimiter
@@ -377,6 +378,29 @@ class TestCheckHealth:
             await task
 
 
+class TestExtraBodyStripped:
+    """issue #4 决策 G: OCR 路径只发 multipart 表单,剥离 extra_body 并 warning。"""
+
+    def test_stripped_with_warning_but_assembly_succeeds(self):
+        messages: list[str] = []
+        sink_id = logger.add(messages.append, level="WARNING")
+        try:
+            client, _, _ = _client([_src(extra_body={"temperature": 0})], ["text"])
+        finally:
+            logger.remove(sink_id)
+        assert client._sources[0].extra_body == {}
+        assert any("extra_body" in m for m in messages)
+
+    async def test_telemetry_never_records_a_parameter_that_was_not_sent(self):
+        """不剥离则审计表会显示这次 OCR 带了 temperature=0——数据造假。"""
+        recorder = _MemoryRecorder()
+        client, _, _ = _client(
+            [_src(extra_body={"temperature": 0})], ["text"], telemetry=recorder
+        )
+        await client.recognize_text(b"IMG")
+        assert recorder.rows[0]["sampling"] is None
+
+
 class TestTelemetry:
     async def test_success_and_failure_recorded_without_image_bytes(self):
         recorder = _MemoryRecorder()