diff --git a/gpt_oss/tools/simple_browser/page_contents.py b/gpt_oss/tools/simple_browser/page_contents.py
index e1e1b95..6fffd3f 100644
--- a/gpt_oss/tools/simple_browser/page_contents.py
+++ b/gpt_oss/tools/simple_browser/page_contents.py
@@ -64,6 +64,7 @@ class Tokens:
 
 
 def get_domain(url: str) -> str:
+    """Extracts the domain from a URL."""
     if "http" not in url:
         # If `get_domain` is called on a domain, add a scheme so that the
         # original domain is returned instead of the empty string.
@@ -72,12 +73,14 @@ def get_domain(url: str) -> str:
 
 
 def multiple_replace(text: str, replacements: dict[str, str]) -> str:
+    """Performs multiple string replacements using regex pass."""
     regex = re.compile("(%s)" % "|".join(map(re.escape, replacements.keys())))
     return regex.sub(lambda mo: replacements[mo.group(1)], text)
 
 
 @functools.lru_cache(maxsize=1024)
 def mark_lines(text: str) -> str:
+    """Adds line numbers (ex: 'L0:') to the beginning of each line in a string."""
     # Split the string by newline characters
     lines = text.split("\n")
 
@@ -88,16 +91,19 @@ def mark_lines(text: str) -> str:
 
 @functools.cache
 def _tiktoken_vocabulary_lengths(enc_name: str) -> list[int]:
+    """Gets the character lengths of all tokens in the specified TikToken vocabulary."""
     encoding = tiktoken.get_encoding(enc_name)
     return [len(encoding.decode([i])) for i in range(encoding.n_vocab)]
 
 
 def warmup_caches(enc_names: list[str]) -> None:
+    """Warm up the cache by computing token length lists for the given TikToken encodings."""
     for _ in map(_tiktoken_vocabulary_lengths, enc_names):
         pass
 
 
 def _replace_special_chars(text: str) -> str:
+    """Replaces specific special characters with visually similar alternatives."""
     replacements = {
         "【": "〖",
         "】": "〗",
@@ -110,16 +116,19 @@ def _replace_special_chars(text: str) -> str:
 
 
 def merge_whitespace(text: str) -> str:
+    """Replace newlines with spaces and merge consecutive whitespace into a single space."""
     text = text.replace("\n", " ")
     text = re.sub(r"\s+", " ", text)
     return text
 
 
 def arxiv_to_ar5iv(url: str) -> str:
+    """Converts an arxiv.org URL to its ar5iv.org equivalent."""
     return re.sub(r"arxiv.org", r"ar5iv.org", url)
 
 
 def _clean_links(root: lxml.html.HtmlElement, cur_url: str) -> dict[str, str]:
+    """Processes all anchor tags in the HTML, replaces them with a custom format and returns an ID-to-URL mapping."""
     cur_domain = get_domain(cur_url)
     urls: dict[str, str] = {}
     urls_rev: dict[str, str] = {}
@@ -156,10 +165,12 @@ def _clean_links(root: lxml.html.HtmlElement, cur_url: str) -> dict[str, str]:
 
 
 def _get_text(node: lxml.html.HtmlElement) -> str:
+    """Extracts all text from an HTML element and merges it into a whitespace-normalized string."""
     return merge_whitespace(" ".join(node.itertext()))
 
 
 def _remove_node(node: lxml.html.HtmlElement) -> None:
+    """Removes a node from its parent in the lxml tree."""
     node.getparent().remove(node)
 
 
@@ -172,6 +183,7 @@ def _escape_md_section(text: str, snob: bool = False) -> str:
 
 
 def html_to_text(html: str) -> str:
+    """Converts an HTML string to clean plaintext."""
     html = re.sub(HTML_SUP_RE, r"^{\2}", html)
     html = re.sub(HTML_SUB_RE, r"_{\2}", html)
     # add spaces between tags such as table cells
@@ -195,6 +207,7 @@ def html_to_text(html: str) -> str:
 
 
 def _remove_math(root: lxml.html.HtmlElement) -> None:
+    """Removes all <math> elements from the lxml tree."""
     for node in root.findall(".//math"):
         _remove_node(node)
 
@@ -209,6 +222,7 @@ def remove_unicode_smp(text: str) -> str:
 
 
 def replace_node_with_text(node: lxml.html.HtmlElement, text: str) -> None:
+    """Replaces an lxml node with a text string while preserving surrounding text."""
     previous = node.getprevious()
     parent = node.getparent()
     tail = node.tail or ""
@@ -224,6 +238,7 @@ def replace_images(
     base_url: str,
     session: aiohttp.ClientSession | None,
 ) -> None:
+    """Finds all image tags and replaces them with numbered placeholders (includes alt/title if available)."""
     cnt = 0
     for img_tag in root.findall(".//img"):
         image_name = img_tag.get("alt", img_tag.get("title"))