From 03f1cd30739d5352677ed8c0dce7ba837648648d Mon Sep 17 00:00:00 2001
From: Chaimaa Abi <118536453+Cha-Imaa@users.noreply.github.com>
Date: Sun, 27 Sep 2026 15:36:39 +0400
Subject: [PATCH 1/4] fix: handle scalar content values in JSONConverter

---
 haystack/components/converters/json.py  |  3 +++
 test/components/converters/test_json.py | 10 ++++++++++
 2 files changed, 13 insertions(+)

diff --git a/haystack/components/converters/json.py b/haystack/components/converters/json.py
index 9510ed9fcb8..300826b196c 100644
--- a/haystack/components/converters/json.py
+++ b/haystack/components/converters/json.py
@@ -238,6 +238,9 @@ def _get_content_and_meta(self, source: ByteStream) -> list[tuple[str, dict[str,
                     logger.warning("Expected a scalar value but got {obj}. Skipping it.", obj=obj)
                     continue
 
+                if text is not None and not isinstance(text, str):
+                    text = str(text)
+
                 meta = {}
                 if meta_fields == "*":
                     meta = {k: v for k, v in obj.items() if k != self._content_key}
diff --git a/test/components/converters/test_json.py b/test/components/converters/test_json.py
index 59fee4875be..83d77dd26cc 100644
--- a/test/components/converters/test_json.py
+++ b/test/components/converters/test_json.py
@@ -511,6 +511,16 @@ def test_run_with_content_key(tmpdir):
     assert result["documents"][2].meta == {}
 
 
+@pytest.mark.parametrize("value, expected", [(123, "123"), (True, "True")])
+def test_run_with_content_key_with_scalar_values(value, expected):
+    source = ByteStream.from_string(json.dumps({"body": value}))
+
+    converter = JSONConverter(content_key="body")
+    result = converter.run(sources=[source])
+
+    assert result["documents"][0].content == expected
+
+
 def test_run_with_content_key_and_extra_meta_fields(tmpdir):
     first_test_file = Path(tmpdir / "first_test_file.json")
     second_test_file = Path(tmpdir / "second_test_file.json")

From 053f01cdff443d1ca46e48bdaff79a7c918e4a9e Mon Sep 17 00:00:00 2001
From: Chaimaa Abi <118536453+Cha-Imaa@users.noreply.github.com>
Date: Mon, 28 Sep 2026 13:27:34 +0400
Subject: [PATCH 2/4] test: cover float and null JSON content values

---
 test/components/converters/test_json.py | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/test/components/converters/test_json.py b/test/components/converters/test_json.py
index 83d77dd26cc..8168051c8b9 100644
--- a/test/components/converters/test_json.py
+++ b/test/components/converters/test_json.py
@@ -511,7 +511,15 @@ def test_run_with_content_key(tmpdir):
     assert result["documents"][2].meta == {}
 
 
-@pytest.mark.parametrize("value, expected", [(123, "123"), (True, "True")])
+@pytest.mark.parametrize(
+    "value, expected",
+    [
+        (123, "123"),
+        (1.5, "1.5"),
+        (True, "True"),
+        (None, None),
+    ],
+)
 def test_run_with_content_key_with_scalar_values(value, expected):
     source = ByteStream.from_string(json.dumps({"body": value}))
 

From a18f8ec39eb4ed7c5d4d34172763e881044482c3 Mon Sep 17 00:00:00 2001
From: Chaimaa Abi <118536453+Cha-Imaa@users.noreply.github.com>
Date: Mon, 28 Sep 2026 13:47:23 +0400
Subject: [PATCH 3/4] docs: add release note for JSONConverter scalar content

---
 .../json-converter-scalar-content-163133a47060a2e7.yaml      | 5 +++++
 1 file changed, 5 insertions(+)
 create mode 100644 releasenotes/notes/json-converter-scalar-content-163133a47060a2e7.yaml

diff --git a/releasenotes/notes/json-converter-scalar-content-163133a47060a2e7.yaml b/releasenotes/notes/json-converter-scalar-content-163133a47060a2e7.yaml
new file mode 100644
index 00000000000..eaf729f667f
--- /dev/null
+++ b/releasenotes/notes/json-converter-scalar-content-163133a47060a2e7.yaml
@@ -0,0 +1,5 @@
+---
+fixes:
+  - |
+    Fixed ``JSONConverter`` failing with ``ValueError`` when ``content_key`` contains numeric or boolean scalar values.
+    These values are now converted to strings before creating the ``Document``, while ``null`` values remain unchanged.

From f4e06f4a11bcff62e5cecad1997109060a9f7f8f Mon Sep 17 00:00:00 2001
From: Chaimaa Abi <118536453+Cha-Imaa@users.noreply.github.com>
Date: Mon, 28 Sep 2026 14:37:07 +0400
Subject: [PATCH 4/4] style: format scalar content regression test

---
 test/components/converters/test_json.py | 10 +---------
 1 file changed, 1 insertion(+), 9 deletions(-)

diff --git a/test/components/converters/test_json.py b/test/components/converters/test_json.py
index 8168051c8b9..c3b5d37f480 100644
--- a/test/components/converters/test_json.py
+++ b/test/components/converters/test_json.py
@@ -511,15 +511,7 @@ def test_run_with_content_key(tmpdir):
     assert result["documents"][2].meta == {}
 
 
-@pytest.mark.parametrize(
-    "value, expected",
-    [
-        (123, "123"),
-        (1.5, "1.5"),
-        (True, "True"),
-        (None, None),
-    ],
-)
+@pytest.mark.parametrize("value, expected", [(123, "123"), (1.5, "1.5"), (True, "True"), (None, None)])
 def test_run_with_content_key_with_scalar_values(value, expected):
     source = ByteStream.from_string(json.dumps({"body": value}))