diff --git a/libs/langchain/langchain/chains/rl_chain/__init__.py b/libs/langchain/langchain/chains/rl_chain/__init__.py
index 6d5cfc3e29c787..3a14861bd7f105 100644
--- a/libs/langchain/langchain/chains/rl_chain/__init__.py
+++ b/libs/langchain/langchain/chains/rl_chain/__init__.py
@@ -9,8 +9,14 @@
     SelectionScorer,
     ToSelectFrom,
     VwPolicy,
+    embed,
+    stringify_embedding,
+)
+from langchain.chains.rl_chain.pick_best_chain import (
+    PickBest,
+    PickBestEvent,
+    PickBestSelected,
 )
-from langchain.chains.rl_chain.pick_best_chain import PickBest
 
 
 def configure_logger() -> None:
@@ -29,6 +35,8 @@ def configure_logger() -> None:
 
 __all__ = [
     "PickBest",
+    "PickBestEvent",
+    "PickBestSelected",
     "Embed",
     "BasedOn",
     "ToSelectFrom",
@@ -37,4 +45,6 @@ def configure_logger() -> None:
     "Embedder",
     "Policy",
     "VwPolicy",
+    "embed",
+    "stringify_embedding",
 ]
diff --git a/libs/langchain/langchain/chains/rl_chain/base.py b/libs/langchain/langchain/chains/rl_chain/base.py
index d08200c7096ce3..6e01bb5063a783 100644
--- a/libs/langchain/langchain/chains/rl_chain/base.py
+++ b/libs/langchain/langchain/chains/rl_chain/base.py
@@ -19,7 +19,10 @@
 from langchain.callbacks.manager import CallbackManagerForChainRun
 from langchain.chains.base import Chain
 from langchain.chains.llm import LLMChain
-from langchain.chains.rl_chain.metrics import MetricsTracker
+from langchain.chains.rl_chain.metrics import (
+    MetricsTrackerAverage,
+    MetricsTrackerRollingWindow,
+)
 from langchain.chains.rl_chain.model_repository import ModelRepository
 from langchain.chains.rl_chain.vw_logger import VwLogger
 from langchain.prompts import (
@@ -98,6 +101,10 @@ def EmbedAndKeep(anything: Any) -> Any:
 # helper functions
 
 
+def stringify_embedding(embedding: List) -> str:
+    return " ".join([f"{i}:{e}" for i, e in enumerate(embedding)])
+
+
 def parse_lines(parser: "vw.TextFormatParser", input_str: str) -> List["vw.Example"]:
     return [parser.parse_line(line) for line in input_str.split("\n")]
 
@@ -346,7 +353,7 @@ def log(self, event: TEvent) -> None:
     selection_scorer_activated: bool = True
     selected_input_key = "rl_chain_selected"
     selected_based_on_input_key = "rl_chain_selected_based_on"
-    metrics: Optional[MetricsTracker] = None
+    metrics: Optional[Union[MetricsTrackerRollingWindow, MetricsTrackerAverage]] = None
 
     def __init__(
         self,
@@ -357,6 +364,7 @@ def __init__(
         policy: Type[Policy] = VwPolicy,
         vw_logs: Optional[Union[str, os.PathLike]] = None,
         metrics_step: int = -1,
+        metrics_window_size: int = -1,
         *args: Any,
         **kwargs: Any,
     ):
@@ -378,7 +386,12 @@ def __init__(
                 vw_logger=VwLogger(vw_logs),
             )
 
-        self.metrics = MetricsTracker(step=metrics_step)
+        if metrics_window_size > 0:
+            self.metrics = MetricsTrackerRollingWindow(
+                step=metrics_step, window_size=metrics_window_size
+            )
+        else:
+            self.metrics = MetricsTrackerAverage(step=metrics_step)
 
     class Config:
         """Configuration for this pydantic object."""
@@ -523,8 +536,9 @@ def _call(
                 f"The selection scorer was not able to score, \
                 and the chain was not able to adjust to this response, error: {e}"
             )
-        if self.metrics:
+        if self.metrics and score is not None:
             self.metrics.on_feedback(score)
+
         event = self._call_after_scoring_before_learning(score=score, event=event)
         self.active_policy.learn(event=event)
         self.active_policy.log(event=event)
@@ -547,16 +561,13 @@ def embed_string_type(
     item: Union[str, _Embed], model: Any, namespace: Optional[str] = None
 ) -> Dict[str, Union[str, List[str]]]:
     """Helper function to embed a string or an _Embed object."""
-    join_char = ""
     keep_str = ""
     if isinstance(item, _Embed):
-        encoded = model.encode(item.value)
-        join_char = " "
+        encoded = stringify_embedding(model.encode(item.value))
         if item.keep:
             keep_str = item.value.replace(" ", "_") + " "
     elif isinstance(item, str):
         encoded = item.replace(" ", "_")
-        join_char = ""
     else:
         raise ValueError(f"Unsupported type {type(item)} for embedding")
 
@@ -566,7 +577,7 @@ def embed_string_type(
                 provided when embedding a string or _Embed object."
         )
 
-    return {namespace: keep_str + join_char.join(map(str, encoded))}
+    return {namespace: keep_str + encoded}
 
 
 def embed_dict_type(item: Dict, model: Any) -> Dict[str, Any]:
diff --git a/libs/langchain/langchain/chains/rl_chain/metrics.py b/libs/langchain/langchain/chains/rl_chain/metrics.py
index 4d6306f7760133..4bd65da3ae537e 100644
--- a/libs/langchain/langchain/chains/rl_chain/metrics.py
+++ b/libs/langchain/langchain/chains/rl_chain/metrics.py
@@ -1,31 +1,66 @@
-from typing import TYPE_CHECKING, Dict, List, Optional, Union
+from collections import deque
+from typing import TYPE_CHECKING, Dict, List, Union
 
 if TYPE_CHECKING:
     import pandas as pd
 
 
-class MetricsTracker:
+class MetricsTrackerAverage:
     def __init__(self, step: int):
-        self._history: List[Dict[str, Union[int, float]]] = []
-        self._step: int = step
-        self._i: int = 0
-        self._num: float = 0
-        self._denom: float = 0
+        self.history: List[Dict[str, Union[int, float]]] = [{"step": 0, "score": 0}]
+        self.step: int = step
+        self.i: int = 0
+        self.num: float = 0
+        self.denom: float = 0
 
     @property
     def score(self) -> float:
-        return self._num / self._denom if self._denom > 0 else 0
+        return self.num / self.denom if self.denom > 0 else 0
 
     def on_decision(self) -> None:
-        self._denom += 1
+        self.denom += 1
 
-    def on_feedback(self, score: Optional[float]) -> None:
-        self._num += score or 0
-        self._i += 1
-        if self._step > 0 and self._i % self._step == 0:
-            self._history.append({"step": self._i, "score": self.score})
+    def on_feedback(self, score: float) -> None:
+        self.num += score or 0
+        self.i += 1
+        if self.step > 0 and self.i % self.step == 0:
+            self.history.append({"step": self.i, "score": self.score})
 
     def to_pandas(self) -> "pd.DataFrame":
         import pandas as pd
 
-        return pd.DataFrame(self._history)
+        return pd.DataFrame(self.history)
+
+
+class MetricsTrackerRollingWindow:
+    def __init__(self, window_size: int, step: int):
+        self.history: List[Dict[str, Union[int, float]]] = [{"step": 0, "score": 0}]
+        self.step: int = step
+        self.i: int = 0
+        self.window_size: int = window_size
+        self.queue: deque = deque()
+        self.sum: float = 0.0
+
+    @property
+    def score(self) -> float:
+        return self.sum / len(self.queue) if len(self.queue) > 0 else 0
+
+    def on_decision(self) -> None:
+        pass
+
+    def on_feedback(self, value: float) -> None:
+        self.sum += value
+        self.queue.append(value)
+        self.i += 1
+
+        if len(self.queue) > self.window_size:
+            old_val = self.queue.popleft()
+            self.sum -= old_val
+
+        if self.step > 0 and self.i % self.step == 0:
+            self.history.append({"step": self.i, "score": self.sum / len(self.queue)})
+
+    def to_pandas(self) -> "pd.DataFrame":
+        import pandas as pd
+
+        return pd.DataFrame(self.history)
diff --git a/libs/langchain/tests/unit_tests/chains/rl_chain/test_pick_best_chain_call.py b/libs/langchain/tests/unit_tests/chains/rl_chain/test_pick_best_chain_call.py
index d4576ce2540bbf..7bfa5ad5506d16 100644
--- a/libs/langchain/tests/unit_tests/chains/rl_chain/test_pick_best_chain_call.py
+++ b/libs/langchain/tests/unit_tests/chains/rl_chain/test_pick_best_chain_call.py
@@ -8,7 +8,7 @@
 from langchain.chat_models import FakeListChatModel
 from langchain.prompts.prompt import PromptTemplate
 
-encoded_text = "[ e n c o d e d ] "
+encoded_keyword = "[encoded]"
 
 
 @pytest.mark.requires("vowpal_wabbit_next", "sentence_transformers")
@@ -176,15 +176,13 @@ def test_auto_embeddings_on() -> None:
     str1 = "0"
     str2 = "1"
     str3 = "2"
-    encoded_str1 = encoded_text + " ".join(char for char in str1)
-    encoded_str2 = encoded_text + " ".join(char for char in str2)
-    encoded_str3 = encoded_text + " ".join(char for char in str3)
+    encoded_str1 = rl_chain.stringify_embedding(list(encoded_keyword + str1))
+    encoded_str2 = rl_chain.stringify_embedding(list(encoded_keyword + str2))
+    encoded_str3 = rl_chain.stringify_embedding(list(encoded_keyword + str3))
 
     ctx_str_1 = "context1"
-    ctx_str_2 = "context2"
 
-    encoded_ctx_str_1 = encoded_text + " ".join(char for char in ctx_str_1)
-    encoded_text + " ".join(char for char in ctx_str_2)
+    encoded_ctx_str_1 = rl_chain.stringify_embedding(list(encoded_keyword + ctx_str_1))
 
     expected = f"""shared |User {ctx_str_1 + " " + encoded_ctx_str_1} \n|action {str1 + " " + encoded_str1} \n|action {str2 + " " + encoded_str2} \n|action {str3 + " " + encoded_str3} """  # noqa
 
@@ -262,15 +260,15 @@ def test_default_embeddings_mixed_w_explicit_user_embeddings() -> None:
     str1 = "0"
     str2 = "1"
     str3 = "2"
-    encoded_str1 = encoded_text + " ".join(char for char in str1)
-    encoded_str2 = encoded_text + " ".join(char for char in str2)
-    encoded_str3 = encoded_text + " ".join(char for char in str3)
+    encoded_str1 = rl_chain.stringify_embedding(list(encoded_keyword + str1))
+    encoded_str2 = rl_chain.stringify_embedding(list(encoded_keyword + str2))
+    encoded_str3 = rl_chain.stringify_embedding(list(encoded_keyword + str3))
 
     ctx_str_1 = "context1"
     ctx_str_2 = "context2"
 
-    encoded_ctx_str_1 = encoded_text + " ".join(char for char in ctx_str_1)
-    encoded_ctx_str_2 = encoded_text + " ".join(char for char in ctx_str_2)
+    encoded_ctx_str_1 = rl_chain.stringify_embedding(list(encoded_keyword + ctx_str_1))
+    encoded_ctx_str_2 = rl_chain.stringify_embedding(list(encoded_keyword + ctx_str_2))
 
     expected = f"""shared |User {encoded_ctx_str_1} |User2 {ctx_str_2 + " " + encoded_ctx_str_2} \n|action {str1 + " " + encoded_str1} \n|action {str2 + " " + encoded_str2} \n|action {encoded_str3} """  # noqa
 
diff --git a/libs/langchain/tests/unit_tests/chains/rl_chain/test_pick_best_text_embedder.py b/libs/langchain/tests/unit_tests/chains/rl_chain/test_pick_best_text_embedder.py
index c49bacac6085c5..8683e3b0e547eb 100644
--- a/libs/langchain/tests/unit_tests/chains/rl_chain/test_pick_best_text_embedder.py
+++ b/libs/langchain/tests/unit_tests/chains/rl_chain/test_pick_best_text_embedder.py
@@ -4,7 +4,7 @@
 import langchain.chains.rl_chain.base as rl_chain
 import langchain.chains.rl_chain.pick_best_chain as pick_best_chain
 
-encoded_text = "[ e n c o d e d ] "
+encoded_keyword = "[encoded]"
 
 
 @pytest.mark.requires("vowpal_wabbit_next")
@@ -80,12 +80,12 @@ def test_pickbest_textembedder_w_full_label_w_emb() -> None:
     str1 = "0"
     str2 = "1"
     str3 = "2"
-    encoded_str1 = encoded_text + " ".join(char for char in str1)
-    encoded_str2 = encoded_text + " ".join(char for char in str2)
-    encoded_str3 = encoded_text + " ".join(char for char in str3)
+    encoded_str1 = rl_chain.stringify_embedding(list(encoded_keyword + str1))
+    encoded_str2 = rl_chain.stringify_embedding(list(encoded_keyword + str2))
+    encoded_str3 = rl_chain.stringify_embedding(list(encoded_keyword + str3))
 
     ctx_str_1 = "context1"
-    encoded_ctx_str_1 = encoded_text + " ".join(char for char in ctx_str_1)
+    encoded_ctx_str_1 = rl_chain.stringify_embedding(list(encoded_keyword + ctx_str_1))
 
     named_actions = {"action1": rl_chain.Embed([str1, str2, str3])}
     context = {"context": rl_chain.Embed(ctx_str_1)}
@@ -104,12 +104,12 @@ def test_pickbest_textembedder_w_full_label_w_embed_and_keep() -> None:
     str1 = "0"
     str2 = "1"
     str3 = "2"
-    encoded_str1 = encoded_text + " ".join(char for char in str1)
-    encoded_str2 = encoded_text + " ".join(char for char in str2)
-    encoded_str3 = encoded_text + " ".join(char for char in str3)
+    encoded_str1 = rl_chain.stringify_embedding(list(encoded_keyword + str1))
+    encoded_str2 = rl_chain.stringify_embedding(list(encoded_keyword + str2))
+    encoded_str3 = rl_chain.stringify_embedding(list(encoded_keyword + str3))
 
     ctx_str_1 = "context1"
-    encoded_ctx_str_1 = encoded_text + " ".join(char for char in ctx_str_1)
+    encoded_ctx_str_1 = rl_chain.stringify_embedding(list(encoded_keyword + ctx_str_1))
 
     named_actions = {"action1": rl_chain.EmbedAndKeep([str1, str2, str3])}
     context = {"context": rl_chain.EmbedAndKeep(ctx_str_1)}
@@ -170,14 +170,14 @@ def test_pickbest_textembedder_more_namespaces_w_full_label_w_full_emb() -> None
     str1 = "0"
     str2 = "1"
     str3 = "2"
-    encoded_str1 = encoded_text + " ".join(char for char in str1)
-    encoded_str2 = encoded_text + " ".join(char for char in str2)
-    encoded_str3 = encoded_text + " ".join(char for char in str3)
+    encoded_str1 = rl_chain.stringify_embedding(list(encoded_keyword + str1))
+    encoded_str2 = rl_chain.stringify_embedding(list(encoded_keyword + str2))
+    encoded_str3 = rl_chain.stringify_embedding(list(encoded_keyword + str3))
 
     ctx_str_1 = "context1"
     ctx_str_2 = "context2"
-    encoded_ctx_str_1 = encoded_text + " ".join(char for char in ctx_str_1)
-    encoded_ctx_str_2 = encoded_text + " ".join(char for char in ctx_str_2)
+    encoded_ctx_str_1 = rl_chain.stringify_embedding(list(encoded_keyword + ctx_str_1))
+    encoded_ctx_str_2 = rl_chain.stringify_embedding(list(encoded_keyword + ctx_str_2))
 
     named_actions = {"action1": rl_chain.Embed([{"a": str1, "b": str1}, str2, str3])}
     context = {
@@ -203,14 +203,14 @@ def test_pickbest_textembedder_more_namespaces_w_full_label_w_full_embed_and_kee
     str1 = "0"
     str2 = "1"
     str3 = "2"
-    encoded_str1 = encoded_text + " ".join(char for char in str1)
-    encoded_str2 = encoded_text + " ".join(char for char in str2)
-    encoded_str3 = encoded_text + " ".join(char for char in str3)
+    encoded_str1 = rl_chain.stringify_embedding(list(encoded_keyword + str1))
+    encoded_str2 = rl_chain.stringify_embedding(list(encoded_keyword + str2))
+    encoded_str3 = rl_chain.stringify_embedding(list(encoded_keyword + str3))
 
     ctx_str_1 = "context1"
     ctx_str_2 = "context2"
-    encoded_ctx_str_1 = encoded_text + " ".join(char for char in ctx_str_1)
-    encoded_ctx_str_2 = encoded_text + " ".join(char for char in ctx_str_2)
+    encoded_ctx_str_1 = rl_chain.stringify_embedding(list(encoded_keyword + ctx_str_1))
+    encoded_ctx_str_2 = rl_chain.stringify_embedding(list(encoded_keyword + ctx_str_2))
 
     named_actions = {
         "action1": rl_chain.EmbedAndKeep([{"a": str1, "b": str1}, str2, str3])
@@ -236,14 +236,12 @@ def test_pickbest_textembedder_more_namespaces_w_full_label_w_partial_emb() -> N
     str1 = "0"
     str2 = "1"
     str3 = "2"
-    encoded_str1 = encoded_text + " ".join(char for char in str1)
-    encoded_text + " ".join(char for char in str2)
-    encoded_str3 = encoded_text + " ".join(char for char in str3)
+    encoded_str1 = rl_chain.stringify_embedding(list(encoded_keyword + str1))
+    encoded_str3 = rl_chain.stringify_embedding(list(encoded_keyword + str3))
 
     ctx_str_1 = "context1"
     ctx_str_2 = "context2"
-    encoded_text + " ".join(char for char in ctx_str_1)
-    encoded_ctx_str_2 = encoded_text + " ".join(char for char in ctx_str_2)
+    encoded_ctx_str_2 = rl_chain.stringify_embedding(list(encoded_keyword + ctx_str_2))
 
     named_actions = {
         "action1": [
@@ -270,14 +268,12 @@ def test_pickbest_textembedder_more_namespaces_w_full_label_w_partial_emakeep()
     str1 = "0"
     str2 = "1"
     str3 = "2"
-    encoded_str1 = encoded_text + " ".join(char for char in str1)
-    encoded_text + " ".join(char for char in str2)
-    encoded_str3 = encoded_text + " ".join(char for char in str3)
+    encoded_str1 = rl_chain.stringify_embedding(list(encoded_keyword + str1))
+    encoded_str3 = rl_chain.stringify_embedding(list(encoded_keyword + str3))
 
     ctx_str_1 = "context1"
     ctx_str_2 = "context2"
-    encoded_text + " ".join(char for char in ctx_str_1)
-    encoded_ctx_str_2 = encoded_text + " ".join(char for char in ctx_str_2)
+    encoded_ctx_str_2 = rl_chain.stringify_embedding(list(encoded_keyword + ctx_str_2))
 
     named_actions = {
         "action1": [
@@ -305,11 +301,11 @@ def test_raw_features_underscored() -> None:
     feature_embedder = pick_best_chain.PickBestFeatureEmbedder(model=MockEncoder())
     str1 = "this is a long string"
     str1_underscored = str1.replace(" ", "_")
-    encoded_str1 = encoded_text + " ".join(char for char in str1)
+    encoded_str1 = rl_chain.stringify_embedding(list(encoded_keyword + str1))
 
     ctx_str = "this is a long context"
     ctx_str_underscored = ctx_str.replace(" ", "_")
-    encoded_ctx_str = encoded_text + " ".join(char for char in ctx_str)
+    encoded_ctx_str = rl_chain.stringify_embedding(list(encoded_keyword + ctx_str))
 
     # No embeddings
     named_actions = {"action": [str1]}
diff --git a/libs/langchain/tests/unit_tests/chains/rl_chain/test_rl_chain_base_embedder.py b/libs/langchain/tests/unit_tests/chains/rl_chain/test_rl_chain_base_embedder.py
index bd0cc584ef1177..1928eb26c606bf 100644
--- a/libs/langchain/tests/unit_tests/chains/rl_chain/test_rl_chain_base_embedder.py
+++ b/libs/langchain/tests/unit_tests/chains/rl_chain/test_rl_chain_base_embedder.py
@@ -5,7 +5,7 @@
 
 import langchain.chains.rl_chain.base as base
 
-encoded_text = "[ e n c o d e d ] "
+encoded_keyword = "[encoded]"
 
 
 @pytest.mark.requires("vowpal_wabbit_next")
@@ -17,12 +17,10 @@ def test_simple_context_str_no_emb() -> None:
 @pytest.mark.requires("vowpal_wabbit_next")
 def test_simple_context_str_w_emb() -> None:
     str1 = "test"
-    encoded_str1 = " ".join(char for char in str1)
-    expected = [{"a_namespace": encoded_text + encoded_str1}]
+    encoded_str1 = base.stringify_embedding(list(encoded_keyword + str1))
+    expected = [{"a_namespace": encoded_str1}]
     assert base.embed(base.Embed(str1), MockEncoder(), "a_namespace") == expected
-    expected_embed_and_keep = [
-        {"a_namespace": str1 + " " + encoded_text + encoded_str1}
-    ]
+    expected_embed_and_keep = [{"a_namespace": str1 + " " + encoded_str1}]
     assert (
         base.embed(base.EmbedAndKeep(str1), MockEncoder(), "a_namespace")
         == expected_embed_and_keep
@@ -33,14 +31,14 @@ def test_simple_context_str_w_emb() -> None:
 def test_simple_context_str_w_nested_emb() -> None:
     # nested embeddings, innermost wins
     str1 = "test"
-    encoded_str1 = " ".join(char for char in str1)
-    expected = [{"a_namespace": encoded_text + encoded_str1}]
+    encoded_str1 = base.stringify_embedding(list(encoded_keyword + str1))
+    expected = [{"a_namespace": encoded_str1}]
     assert (
         base.embed(base.EmbedAndKeep(base.Embed(str1)), MockEncoder(), "a_namespace")
         == expected
     )
 
-    expected2 = [{"a_namespace": str1 + " " + encoded_text + encoded_str1}]
+    expected2 = [{"a_namespace": str1 + " " + encoded_str1}]
     assert (
         base.embed(base.Embed(base.EmbedAndKeep(str1)), MockEncoder(), "a_namespace")
         == expected2
@@ -56,12 +54,10 @@ def test_context_w_namespace_no_emb() -> None:
 @pytest.mark.requires("vowpal_wabbit_next")
 def test_context_w_namespace_w_emb() -> None:
     str1 = "test"
-    encoded_str1 = " ".join(char for char in str1)
-    expected = [{"test_namespace": encoded_text + encoded_str1}]
+    encoded_str1 = base.stringify_embedding(list(encoded_keyword + str1))
+    expected = [{"test_namespace": encoded_str1}]
     assert base.embed({"test_namespace": base.Embed(str1)}, MockEncoder()) == expected
-    expected_embed_and_keep = [
-        {"test_namespace": str1 + " " + encoded_text + encoded_str1}
-    ]
+    expected_embed_and_keep = [{"test_namespace": str1 + " " + encoded_str1}]
     assert (
         base.embed({"test_namespace": base.EmbedAndKeep(str1)}, MockEncoder())
         == expected_embed_and_keep
@@ -71,12 +67,10 @@ def test_context_w_namespace_w_emb() -> None:
 @pytest.mark.requires("vowpal_wabbit_next")
 def test_context_w_namespace_w_emb2() -> None:
     str1 = "test"
-    encoded_str1 = " ".join(char for char in str1)
-    expected = [{"test_namespace": encoded_text + encoded_str1}]
+    encoded_str1 = base.stringify_embedding(list(encoded_keyword + str1))
+    expected = [{"test_namespace": encoded_str1}]
     assert base.embed(base.Embed({"test_namespace": str1}), MockEncoder()) == expected
-    expected_embed_and_keep = [
-        {"test_namespace": str1 + " " + encoded_text + encoded_str1}
-    ]
+    expected_embed_and_keep = [{"test_namespace": str1 + " " + encoded_str1}]
     assert (
         base.embed(base.EmbedAndKeep({"test_namespace": str1}), MockEncoder())
         == expected_embed_and_keep
@@ -87,10 +81,8 @@ def test_context_w_namespace_w_emb2() -> None:
 def test_context_w_namespace_w_some_emb() -> None:
     str1 = "test1"
     str2 = "test2"
-    encoded_str2 = " ".join(char for char in str2)
-    expected = [
-        {"test_namespace": str1, "test_namespace2": encoded_text + encoded_str2}
-    ]
+    encoded_str2 = base.stringify_embedding(list(encoded_keyword + str2))
+    expected = [{"test_namespace": str1, "test_namespace2": encoded_str2}]
     assert (
         base.embed(
             {"test_namespace": str1, "test_namespace2": base.Embed(str2)}, MockEncoder()
@@ -100,7 +92,7 @@ def test_context_w_namespace_w_some_emb() -> None:
     expected_embed_and_keep = [
         {
             "test_namespace": str1,
-            "test_namespace2": str2 + " " + encoded_text + encoded_str2,
+            "test_namespace2": str2 + " " + encoded_str2,
         }
     ]
     assert (
@@ -127,22 +119,22 @@ def test_simple_action_strlist_w_emb() -> None:
     str1 = "test1"
     str2 = "test2"
     str3 = "test3"
-    encoded_str1 = " ".join(char for char in str1)
-    encoded_str2 = " ".join(char for char in str2)
-    encoded_str3 = " ".join(char for char in str3)
+    encoded_str1 = base.stringify_embedding(list(encoded_keyword + str1))
+    encoded_str2 = base.stringify_embedding(list(encoded_keyword + str2))
+    encoded_str3 = base.stringify_embedding(list(encoded_keyword + str3))
     expected = [
-        {"a_namespace": encoded_text + encoded_str1},
-        {"a_namespace": encoded_text + encoded_str2},
-        {"a_namespace": encoded_text + encoded_str3},
+        {"a_namespace": encoded_str1},
+        {"a_namespace": encoded_str2},
+        {"a_namespace": encoded_str3},
     ]
     assert (
         base.embed(base.Embed([str1, str2, str3]), MockEncoder(), "a_namespace")
         == expected
     )
     expected_embed_and_keep = [
-        {"a_namespace": str1 + " " + encoded_text + encoded_str1},
-        {"a_namespace": str2 + " " + encoded_text + encoded_str2},
-        {"a_namespace": str3 + " " + encoded_text + encoded_str3},
+        {"a_namespace": str1 + " " + encoded_str1},
+        {"a_namespace": str2 + " " + encoded_str2},
+        {"a_namespace": str3 + " " + encoded_str3},
     ]
     assert (
         base.embed(base.EmbedAndKeep([str1, str2, str3]), MockEncoder(), "a_namespace")
@@ -155,12 +147,12 @@ def test_simple_action_strlist_w_some_emb() -> None:
     str1 = "test1"
     str2 = "test2"
     str3 = "test3"
-    encoded_str2 = " ".join(char for char in str2)
-    encoded_str3 = " ".join(char for char in str3)
+    encoded_str2 = base.stringify_embedding(list(encoded_keyword + str2))
+    encoded_str3 = base.stringify_embedding(list(encoded_keyword + str3))
     expected = [
         {"a_namespace": str1},
-        {"a_namespace": encoded_text + encoded_str2},
-        {"a_namespace": encoded_text + encoded_str3},
+        {"a_namespace": encoded_str2},
+        {"a_namespace": encoded_str3},
     ]
     assert (
         base.embed(
@@ -170,8 +162,8 @@ def test_simple_action_strlist_w_some_emb() -> None:
     )
     expected_embed_and_keep = [
         {"a_namespace": str1},
-        {"a_namespace": str2 + " " + encoded_text + encoded_str2},
-        {"a_namespace": str3 + " " + encoded_text + encoded_str3},
+        {"a_namespace": str2 + " " + encoded_str2},
+        {"a_namespace": str3 + " " + encoded_str3},
     ]
     assert (
         base.embed(
@@ -211,13 +203,13 @@ def test_action_w_namespace_w_emb() -> None:
     str1 = "test1"
     str2 = "test2"
     str3 = "test3"
-    encoded_str1 = " ".join(char for char in str1)
-    encoded_str2 = " ".join(char for char in str2)
-    encoded_str3 = " ".join(char for char in str3)
+    encoded_str1 = base.stringify_embedding(list(encoded_keyword + str1))
+    encoded_str2 = base.stringify_embedding(list(encoded_keyword + str2))
+    encoded_str3 = base.stringify_embedding(list(encoded_keyword + str3))
     expected = [
-        {"test_namespace": encoded_text + encoded_str1},
-        {"test_namespace": encoded_text + encoded_str2},
-        {"test_namespace": encoded_text + encoded_str3},
+        {"test_namespace": encoded_str1},
+        {"test_namespace": encoded_str2},
+        {"test_namespace": encoded_str3},
     ]
     assert (
         base.embed(
@@ -231,9 +223,9 @@ def test_action_w_namespace_w_emb() -> None:
         == expected
     )
     expected_embed_and_keep = [
-        {"test_namespace": str1 + " " + encoded_text + encoded_str1},
-        {"test_namespace": str2 + " " + encoded_text + encoded_str2},
-        {"test_namespace": str3 + " " + encoded_text + encoded_str3},
+        {"test_namespace": str1 + " " + encoded_str1},
+        {"test_namespace": str2 + " " + encoded_str2},
+        {"test_namespace": str3 + " " + encoded_str3},
     ]
     assert (
         base.embed(
@@ -253,13 +245,13 @@ def test_action_w_namespace_w_emb2() -> None:
     str1 = "test1"
     str2 = "test2"
     str3 = "test3"
-    encoded_str1 = " ".join(char for char in str1)
-    encoded_str2 = " ".join(char for char in str2)
-    encoded_str3 = " ".join(char for char in str3)
+    encoded_str1 = base.stringify_embedding(list(encoded_keyword + str1))
+    encoded_str2 = base.stringify_embedding(list(encoded_keyword + str2))
+    encoded_str3 = base.stringify_embedding(list(encoded_keyword + str3))
     expected = [
-        {"test_namespace1": encoded_text + encoded_str1},
-        {"test_namespace2": encoded_text + encoded_str2},
-        {"test_namespace3": encoded_text + encoded_str3},
+        {"test_namespace1": encoded_str1},
+        {"test_namespace2": encoded_str2},
+        {"test_namespace3": encoded_str3},
     ]
     assert (
         base.embed(
@@ -275,9 +267,9 @@ def test_action_w_namespace_w_emb2() -> None:
         == expected
     )
     expected_embed_and_keep = [
-        {"test_namespace1": str1 + " " + encoded_text + encoded_str1},
-        {"test_namespace2": str2 + " " + encoded_text + encoded_str2},
-        {"test_namespace3": str3 + " " + encoded_text + encoded_str3},
+        {"test_namespace1": str1 + " " + encoded_str1},
+        {"test_namespace2": str2 + " " + encoded_str2},
+        {"test_namespace3": str3 + " " + encoded_str3},
     ]
     assert (
         base.embed(
@@ -299,12 +291,12 @@ def test_action_w_namespace_w_some_emb() -> None:
     str1 = "test1"
     str2 = "test2"
     str3 = "test3"
-    encoded_str2 = " ".join(char for char in str2)
-    encoded_str3 = " ".join(char for char in str3)
+    encoded_str2 = base.stringify_embedding(list(encoded_keyword + str2))
+    encoded_str3 = base.stringify_embedding(list(encoded_keyword + str3))
     expected = [
         {"test_namespace": str1},
-        {"test_namespace": encoded_text + encoded_str2},
-        {"test_namespace": encoded_text + encoded_str3},
+        {"test_namespace": encoded_str2},
+        {"test_namespace": encoded_str3},
     ]
     assert (
         base.embed(
@@ -319,8 +311,8 @@ def test_action_w_namespace_w_some_emb() -> None:
     )
     expected_embed_and_keep = [
         {"test_namespace": str1},
-        {"test_namespace": str2 + " " + encoded_text + encoded_str2},
-        {"test_namespace": str3 + " " + encoded_text + encoded_str3},
+        {"test_namespace": str2 + " " + encoded_str2},
+        {"test_namespace": str3 + " " + encoded_str3},
     ]
     assert (
         base.embed(
@@ -340,13 +332,13 @@ def test_action_w_namespace_w_emb_w_more_than_one_item_in_first_dict() -> None:
     str1 = "test1"
     str2 = "test2"
     str3 = "test3"
-    encoded_str1 = " ".join(char for char in str1)
-    encoded_str2 = " ".join(char for char in str2)
-    encoded_str3 = " ".join(char for char in str3)
+    encoded_str1 = base.stringify_embedding(list(encoded_keyword + str1))
+    encoded_str2 = base.stringify_embedding(list(encoded_keyword + str2))
+    encoded_str3 = base.stringify_embedding(list(encoded_keyword + str3))
     expected = [
-        {"test_namespace": encoded_text + encoded_str1, "test_namespace2": str1},
-        {"test_namespace": encoded_text + encoded_str2, "test_namespace2": str2},
-        {"test_namespace": encoded_text + encoded_str3, "test_namespace2": str3},
+        {"test_namespace": encoded_str1, "test_namespace2": str1},
+        {"test_namespace": encoded_str2, "test_namespace2": str2},
+        {"test_namespace": encoded_str3, "test_namespace2": str3},
     ]
     assert (
         base.embed(
@@ -361,15 +353,15 @@ def test_action_w_namespace_w_emb_w_more_than_one_item_in_first_dict() -> None:
     )
     expected_embed_and_keep = [
         {
-            "test_namespace": str1 + " " + encoded_text + encoded_str1,
+            "test_namespace": str1 + " " + encoded_str1,
             "test_namespace2": str1,
         },
         {
-            "test_namespace": str2 + " " + encoded_text + encoded_str2,
+            "test_namespace": str2 + " " + encoded_str2,
             "test_namespace2": str2,
         },
         {
-            "test_namespace": str3 + " " + encoded_text + encoded_str3,
+            "test_namespace": str3 + " " + encoded_str3,
             "test_namespace2": str3,
         },
     ]
@@ -398,8 +390,8 @@ def test_one_namespace_w_list_of_features_no_emb() -> None:
 def test_one_namespace_w_list_of_features_w_some_emb() -> None:
     str1 = "test1"
     str2 = "test2"
-    encoded_str2 = " ".join(char for char in str2)
-    expected = [{"test_namespace": [str1, encoded_text + encoded_str2]}]
+    encoded_str2 = base.stringify_embedding(list(encoded_keyword + str2))
+    expected = [{"test_namespace": [str1, encoded_str2]}]
     assert (
         base.embed({"test_namespace": [str1, base.Embed(str2)]}, MockEncoder())
         == expected