diff --git a/docs/tutorials/_quarto.yml b/docs/tutorials/_quarto.yml
index a48d2b44..2eed4b30 100644
--- a/docs/tutorials/_quarto.yml
+++ b/docs/tutorials/_quarto.yml
@@ -1,7 +1,7 @@
 project:
   title: "PyRenew Tutorials"
   pre-render: uv run ../../docs_scripts/cleanup_generated_md.py . # remove generated .md files
-  post-render: uv run ../../docs_scripts/add_markdown_to_divs.py . # see https://squidfunk.github.io/mkdocs-material/setup/extensions/python-markdown/#markdown-in-html
+  post-render: uv run ../../docs_scripts/postprocess_generated_markdown.py . # see https://squidfunk.github.io/mkdocs-material/setup/extensions/python-markdown/#markdown-in-html
 
 format: gfm
 engine: jupyter
diff --git a/docs_scripts/add_markdown_to_divs.py b/docs_scripts/add_markdown_to_divs.py
deleted file mode 100644
index f13aee48..00000000
--- a/docs_scripts/add_markdown_to_divs.py
+++ /dev/null
@@ -1,32 +0,0 @@
-# numpydoc ignore=GL08
-
-import sys
-from pathlib import Path
-
-from bs4 import BeautifulSoup
-
-
-def add_markdown_to_divs(html: str) -> str:  # numpydoc ignore=GL08
-    soup = BeautifulSoup(html, "html.parser")
-    for div in soup.find_all("div"):
-        if "markdown" not in div.attrs:
-            div["markdown"] = "1"
-    for img in soup.find_all("img"):
-        img.attrs.pop("width", None)
-        img.attrs.pop("height", None)
-    return soup.decode(formatter=None)
-
-
-if __name__ == "__main__":
-    target = Path(sys.argv[1])
-    if target.is_file():
-        text = target.read_text(encoding="utf-8")
-        updated = add_markdown_to_divs(text)
-        target.write_text(updated, encoding="utf-8")
-        print(f"Processed {target}")
-    elif target.is_dir():
-        for f in target.rglob("*.md"):
-            text = f.read_text(encoding="utf-8")
-            updated = add_markdown_to_divs(text)
-            f.write_text(updated, encoding="utf-8")
-            print(f"Processed {f}")
diff --git a/docs_scripts/postprocess_generated_markdown.py b/docs_scripts/postprocess_generated_markdown.py
new file mode 100644
index 00000000..5f4a90ef
--- /dev/null
+++ b/docs_scripts/postprocess_generated_markdown.py
@@ -0,0 +1,62 @@
+# numpydoc ignore=GL08
+
+import sys
+from pathlib import Path
+
+from bs4 import BeautifulSoup
+from bs4.element import Tag
+
+
+def _next_tag(element: Tag) -> Tag | None:  # numpydoc ignore=GL08
+    for sibling in element.next_siblings:
+        if isinstance(sibling, Tag):
+            return sibling
+        if str(sibling).strip():
+            return None
+    return None
+
+
+def _add_alt_text_paragraphs(soup: BeautifulSoup) -> None:  # numpydoc ignore=GL08
+    for img in soup.find_all("img"):
+        alt_text = img.get("alt", "").strip()
+        if not alt_text:
+            continue
+
+        next_tag = _next_tag(img)
+        if (
+            next_tag
+            and next_tag.name == "p"
+            and next_tag.get_text(strip=True) == alt_text
+        ):
+            continue
+
+        caption = soup.new_tag("p")
+        caption.string = alt_text
+        img.insert_after(caption)
+
+
+def postprocess_generated_markdown(html: str) -> str:  # numpydoc ignore=GL08
+    soup = BeautifulSoup(html, "html.parser")
+    for div in soup.find_all("div"):
+        if "markdown" not in div.attrs:
+            div["markdown"] = "1"
+    for img in soup.find_all("img"):
+        img.attrs.pop("width", None)
+        img.attrs.pop("height", None)
+    _add_alt_text_paragraphs(soup)
+    return soup.decode(formatter=None)
+
+
+if __name__ == "__main__":
+    target = Path(sys.argv[1])
+    if target.is_file():
+        text = target.read_text(encoding="utf-8")
+        updated = postprocess_generated_markdown(text)
+        target.write_text(updated, encoding="utf-8")
+        print(f"Processed {target}")
+    elif target.is_dir():
+        for f in target.rglob("*.md"):
+            text = f.read_text(encoding="utf-8")
+            updated = postprocess_generated_markdown(text)
+            f.write_text(updated, encoding="utf-8")
+            print(f"Processed {f}")
diff --git a/test/test_docs_postprocessing.py b/test/test_docs_postprocessing.py
new file mode 100644
index 00000000..417280bf
--- /dev/null
+++ b/test/test_docs_postprocessing.py
@@ -0,0 +1,39 @@
+# numpydoc ignore=GL08
+
+import importlib.util
+from pathlib import Path
+
+
+def _load_postprocessor():  # numpydoc ignore=GL08
+    script_path = (
+        Path(__file__).parents[1] / "docs_scripts" / "postprocess_generated_markdown.py"
+    )
+    spec = importlib.util.spec_from_file_location(
+        "postprocess_generated_markdown", script_path
+    )
+    module = importlib.util.module_from_spec(spec)
+    spec.loader.exec_module(module)
+    return module
+
+
+def test_postprocess_generated_markdown_adds_alt_text_paragraph():  # numpydoc ignore=GL08
+    postprocessor = _load_postprocessor()
+
+    result = postprocessor.postprocess_generated_markdown(
+        '<div><img alt="Figure caption." height="400" src="plot.png" width="600"/></div>'
+    )
+
+    assert result == (
+        '<div markdown="1"><img alt="Figure caption." src="plot.png"/>'
+        "<p>Figure caption.</p></div>"
+    )
+
+
+def test_postprocess_generated_markdown_does_not_duplicate_alt_text_paragraph():  # numpydoc ignore=GL08
+    postprocessor = _load_postprocessor()
+
+    result = postprocessor.postprocess_generated_markdown(
+        '<img alt="Figure caption." src="plot.png"/><p>Figure caption.</p>'
+    )
+
+    assert result == '<img alt="Figure caption." src="plot.png"/><p>Figure caption.</p>'