diff --git a/nanobot/utils/helpers.py b/nanobot/utils/helpers.py
index c545e9ca..32824aaf 100644
--- a/nanobot/utils/helpers.py
+++ b/nanobot/utils/helpers.py
@@ -65,6 +65,27 @@ def _estimate_tools_tokens(
     return token_count
 
 
+def _tag_regex(tags: tuple[str, ...]) -> str:
+    return rf"(?:{'|'.join(re.escape(tag) for tag in tags)})"
+
+
+_THINKING_TAGS = ("think", "thinking", "thought")
+_INLINE_SELF_CLOSING_PRESERVED_TAGS = frozenset({"think", "thought"})
+_INLINE_SELF_CLOSING_THINKING_TAGS = tuple(
+    tag for tag in _THINKING_TAGS if tag not in _INLINE_SELF_CLOSING_PRESERVED_TAGS
+)
+_THINKING_TAG = _tag_regex(_THINKING_TAGS)
+_INLINE_SELF_CLOSING_THINKING_TAG = _tag_regex(_INLINE_SELF_CLOSING_THINKING_TAGS)
+_THINKING_TAG_PREFIX = "|".join(
+    sorted(
+        {re.escape(tag[:i]) for tag in _THINKING_TAGS for i in range(1, len(tag) + 1)},
+        key=len,
+        reverse=True,
+    )
+)
+_PARTIAL_THINKING_TAG = rf"</?(?:{_THINKING_TAG_PREFIX})>?"
+
+
 def strip_think(text: str) -> str:
     """Remove thinking blocks, unclosed trailing tags, and tokenizer-level
     template leaks occasionally emitted by some models (notably Gemma 4's
@@ -92,38 +113,28 @@ def strip_think(text: str) -> str:
     assistant discusses the tokens themselves.
     """
     # Well-formed blocks first.
-    text = re.sub(r"<think>[\s\S]*?</think>", "", text)
-    text = re.sub(r"^\s*<think>[\s\S]*$", "", text)
-    text = re.sub(r"<thinking>[\s\S]*?</thinking>", "", text)
-    text = re.sub(r"^\s*<thinking>[\s\S]*$", "", text)
-    text = re.sub(r"<thought>[\s\S]*?</thought>", "", text)
-    text = re.sub(r"^\s*<thought>[\s\S]*$", "", text)
+    text = re.sub(rf"<(?P<tag>{_THINKING_TAG})>[\s\S]*?</(?P=tag)>", "", text)
+    text = re.sub(rf"^\s*<{_THINKING_TAG}>[\s\S]*$", "", text)
     # Self-closing `<thinking/>` is an empty marker, not user-visible text.
-    text = re.sub(r"^\s*<thinking/>\s*", "", text)
-    text = re.sub(r"\s*<thinking/>\s*$", "", text)
+    text = re.sub(rf"^\s*<{_INLINE_SELF_CLOSING_THINKING_TAG}/>\s*", "", text)
+    text = re.sub(rf"\s*<{_INLINE_SELF_CLOSING_THINKING_TAG}/>\s*$", "", text)
     # Malformed opening tags: `<think` / `<thinking` / `<thought` where the next char is
     # NOT one that could continue a valid tag / identifier name. Explicitly
     # listing ASCII tag-name chars (letters, digits, `_`, `-`, `:`) plus
     # `>` / `/` — we can't use `\w` here because in Python's default
     # Unicode regex mode it matches CJK characters too, which would defeat
     # the primary fix for `<think广场…` leaks.
-    text = re.sub(r"<think(?![A-Za-z0-9_\-:>/])", "", text)
-    text = re.sub(r"<thinking(?![A-Za-z0-9_\-:>/])", "", text)
-    text = re.sub(r"<thought(?![A-Za-z0-9_\-:>/])", "", text)
+    text = re.sub(rf"<{_THINKING_TAG}(?![A-Za-z0-9_\-:>/])", "", text)
     # Edge-only orphan closing tags (start or end of text).
-    text = re.sub(r"^\s*</think>\s*", "", text)
-    text = re.sub(r"\s*</think>\s*$", "", text)
-    text = re.sub(r"^\s*</thinking>\s*", "", text)
-    text = re.sub(r"\s*</thinking>\s*$", "", text)
-    text = re.sub(r"^\s*</thought>\s*", "", text)
-    text = re.sub(r"\s*</thought>\s*$", "", text)
+    text = re.sub(rf"^\s*</{_THINKING_TAG}>\s*", "", text)
+    text = re.sub(rf"\s*</{_THINKING_TAG}>\s*$", "", text)
     # Edge-only channel markers (harmony / Gemma 4 variant leaks).
     text = re.sub(r"^\s*<\|?channel\|?>\s*", "", text)
     # Stream chunks may end in the middle of a control tag. Strip only known
     # control-token prefixes at the very end.
     partial_control_tag = (
-        r"</?(?:t|th|thi|thin|think|thinki|thinkin|thinking|tho|thou|thoug|though|thought)>?"
-        r"|<\|?(?:c|ch|cha|chan|chann|channe|channel)(?:\|?>?)?"
+        rf"{_PARTIAL_THINKING_TAG}|"
+        r"<\|?(?:c|ch|cha|chan|chann|channe|channel)(?:\|?>?)?"
     )
     text = re.sub(rf"(?:{partial_control_tag})$", "", text)
     text = re.sub(r"^\s*<\|?$", "", text)
@@ -134,15 +145,12 @@ def strip_reasoning_tags(text: object) -> str:
     """Remove wrapper tags from text that is already known to be reasoning."""
     if not isinstance(text, str):
         return ""
-    partial_reasoning_tag = (
-        r"</?(?:t|th|thi|thin|think|thinki|thinkin|thinking|tho|thou|thoug|though|thought)>?"
-    )
-    text = re.sub(rf"^\s*(?:{partial_reasoning_tag})$", "", text)
-    text = re.sub(r"^\s*<(?:think|thinking|thought)/>\s*", "", text)
-    text = re.sub(r"\s*<(?:think|thinking|thought)/>\s*$", "", text)
-    text = re.sub(r"^\s*<(?:think|thinking|thought)>\s*", "", text)
-    text = re.sub(r"\s*</(?:think|thinking|thought)>\s*$", "", text)
-    text = re.sub(rf"\s*(?:{partial_reasoning_tag})$", "", text)
+    text = re.sub(rf"^\s*(?:{_PARTIAL_THINKING_TAG})$", "", text)
+    text = re.sub(rf"^\s*<{_THINKING_TAG}/>\s*", "", text)
+    text = re.sub(rf"\s*<{_THINKING_TAG}/>\s*$", "", text)
+    text = re.sub(rf"^\s*<{_THINKING_TAG}>\s*", "", text)
+    text = re.sub(rf"\s*</{_THINKING_TAG}>\s*$", "", text)
+    text = re.sub(rf"\s*(?:{_PARTIAL_THINKING_TAG})$", "", text)
     return text.strip()
 
 
@@ -154,12 +162,8 @@ def extract_think(text: str) -> tuple[str | None, str]:
     text but not surfaced — :func:`strip_think` handles that case.
     """
     parts: list[str] = []
-    for m in re.finditer(r"<think>([\s\S]*?)</think>", text):
-        parts.append(m.group(1).strip())
-    for m in re.finditer(r"<thinking>([\s\S]*?)</thinking>", text):
-        parts.append(m.group(1).strip())
-    for m in re.finditer(r"<thought>([\s\S]*?)</thought>", text):
-        parts.append(m.group(1).strip())
+    for m in re.finditer(rf"<(?P<tag>{_THINKING_TAG})>([\s\S]*?)</(?P=tag)>", text):
+        parts.append(m.group(2).strip())
     thinking = "\n\n".join(parts) if parts else None
     return thinking, strip_think(text)