From 371964e4a7e54d904f24f00050a640f24594f25f Mon Sep 17 00:00:00 2001
From: Maximilian Linhoff <maximilian.linhoff@tu-dortmund.de>
Date: Thu, 18 Jul 2024 15:12:53 +0200
Subject: [PATCH 1/3] Add functions to read reference metadata

---
 src/ctapipe/io/hdf5merger.py          |   2 +-
 src/ctapipe/io/metadata.py            |  83 +++++++++++++++----
 src/ctapipe/io/tests/test_metadata.py | 111 +++++++++++---------------
 3 files changed, 116 insertions(+), 80 deletions(-)

diff --git a/src/ctapipe/io/hdf5merger.py b/src/ctapipe/io/hdf5merger.py
index 4161dba0878..58b98a78070 100644
--- a/src/ctapipe/io/hdf5merger.py
+++ b/src/ctapipe/io/hdf5merger.py
@@ -247,7 +247,7 @@ def _update_meta(self):
 
     def _read_meta(self, h5file):
         try:
-            return metadata.Reference.from_dict(metadata.read_metadata(h5file))
+            return metadata.read_reference_metadata_hdf5(h5file)
         except Exception:
             raise CannotMerge(
                 f"CTA Reference meta not found in input file: {h5file.filename}"
diff --git a/src/ctapipe/io/metadata.py b/src/ctapipe/io/metadata.py
index b4fd670144f..2aef43d111e 100644
--- a/src/ctapipe/io/metadata.py
+++ b/src/ctapipe/io/metadata.py
@@ -22,6 +22,7 @@
     some_astropy_table.write("output.ecsv")
 
 """
+import gzip
 import os
 import uuid
 import warnings
@@ -29,6 +30,8 @@
 from contextlib import ExitStack
 
 import tables
+from astropy.io import fits
+from astropy.table import Table
 from astropy.time import Time
 from tables import NaturalNameWarning
 from traitlets import Enum, HasTraits, Instance, List, Unicode, UseEnum, default
@@ -45,7 +48,8 @@
     "Activity",
     "Instrument",
     "write_to_hdf5",
-    "read_metadata",
+    "read_hdf5_metadata",
+    "read_reference_metadata",
 ]
 
 
@@ -295,6 +299,12 @@ def from_dict(cls, metadata):
             instrument=Instrument(**kwargs["instrument"]),
         )
 
+    @classmethod
+    def from_fits(cls, header):
+        # for now, just use from_dict, but we might need special handling
+        # of some keys
+        return cls.from_dict(header)
+
     def __repr__(self):
         return str(self.to_dict())
 
@@ -320,27 +330,72 @@ def write_to_hdf5(metadata, h5file, path="/"):
             node._v_attrs[key] = value  # pylint: disable=protected-access
 
 
-def read_metadata(h5file, path="/"):
+def read_hdf5_metadata(h5file, path="/"):
+    """
+    Read hdf5 attributes into a dict
+    """
+    with ExitStack() as stack:
+        if not isinstance(h5file, tables.File):
+            h5file = stack.enter_context(tables.open_file(h5file))
+
+        node = h5file.get_node(path)
+        return {key: node._v_attrs[key] for key in node._v_attrs._f_list()}
+
+
+def read_reference_metadata(path):
+    """Read CTAO data product metadata from path
+
+    File is first opened to determine file format, then the metadata
+    is read. Supported are currently FITS and HDF5.
     """
-    Read metadata from an hdf5 file
+    header_bytes = 8
+    with open(path, "rb") as f:
+        first_bytes = f.read(header_bytes)
+
+    if first_bytes.startswith(b"\x1f\x8b"):
+        with gzip.open(path, "rb") as f:
+            first_bytes = f.read(header_bytes)
+
+    if first_bytes.startswith(b"\x89HDF"):
+        return _read_reference_metadata_hdf5(path)
+
+    if first_bytes.startswith(b"SIMPLE"):
+        return _read_reference_metadata_fits(path)
+
+    if first_bytes.startswith(b"# %ECSV"):
+        return Reference.from_dict(Table.read(path).meta)
+
+    raise ValueError(
+        f"'{path}' is not one of the supported file formats: fits, hdf5, ecsv"
+    )
+
+
+def _read_reference_metadata_hdf5(h5file, path="/"):
+    meta = read_hdf5_metadata(h5file, path)
+    return Reference.from_dict(meta)
+
+
+def _read_reference_metadata_ecsv(path):
+    return Reference.from_dict(Table.read(path).meta)
+
+
+def _read_reference_metadata_fits(fitsfile, hdu: int | str = 0):
+    """
+    Read reference metadata from a fits file
 
     Parameters
     ----------
-    h5filename: string, Path, or `tables.file.File`
+    fitsfile: string, Path, or `tables.file.File`
         hdf5 file
-    path: string
-        default: '/' is the path to ctapipe global metadata
+    hdu: int or str
+        HDU index or name.
 
     Returns
     -------
-    metadata: dictionary
+    reference_metadata: Reference
     """
     with ExitStack() as stack:
-        if not isinstance(h5file, tables.File):
-            h5file = stack.enter_context(tables.open_file(h5file))
-
-        node = h5file.get_node(path)
-        metadata = {key: node._v_attrs[key] for key in node._v_attrs._f_list()}
-        return metadata
+        if not isinstance(fitsfile, fits.HDUList):
+            fitsfile = stack.enter_context(fits.open(fitsfile))
 
-    raise OSError("Could not read metadata")
+        return Reference.from_fits(fitsfile[hdu].header)
diff --git a/src/ctapipe/io/tests/test_metadata.py b/src/ctapipe/io/tests/test_metadata.py
index a69e9be76ab..aa242b0448f 100644
--- a/src/ctapipe/io/tests/test_metadata.py
+++ b/src/ctapipe/io/tests/test_metadata.py
@@ -1,16 +1,19 @@
 """
 Test CTA Reference metadata functionality
 """
+import uuid
 
+import pytest
 import tables
+from astropy.io import fits
+from astropy.table import Table
 
 from ctapipe.core.provenance import Provenance
 from ctapipe.io import metadata as meta
 
 
-def test_construct_and_write_metadata(tmp_path):
-    """basic test of making a Reference object and writing it"""
-
+@pytest.fixture()
+def reference():
     prov = Provenance()
     prov.start_activity("test")
     prov.finish_activity()
@@ -43,41 +46,58 @@ def test_construct_and_write_metadata(tmp_path):
             id_="threshold",
         ),
     )
+    return reference
+
 
+def test_to_dict(reference):
+    """Test for Reference.to_dict"""
     ref_dict = reference.to_dict()
     assert ref_dict["CTA PRODUCT FORMAT"] == "hdf5"
     assert ref_dict["CTA PRODUCT DATA LEVELS"] == "DL1_IMAGES,DL1_PARAMETERS"
+    assert str(uuid.UUID(ref_dict["CTA PRODUCT ID"])) == ref_dict["CTA PRODUCT ID"]
 
-    import uuid  # pylint: disable=import-outside-toplevel
 
-    assert str(uuid.UUID(ref_dict["CTA PRODUCT ID"])) == ref_dict["CTA PRODUCT ID"]
+def test_from_dict(reference):
+    as_dict = reference.to_dict()
+    back = meta.Reference.from_dict(as_dict)
+    assert back.to_dict() == as_dict
+
+
+@pytest.mark.parametrize("format", ("fits", "fits.gz"))
+def test_reference_metadata_fits(tmp_path, format, reference):
+    """Test for writing reference metadata"""
+    path = tmp_path / f"test.{format}"
+
+    hdul = fits.HDUList(fits.PrimaryHDU())
+    hdul[0].header.update(reference.to_dict(fits=True))
+    hdul.writeto(path)
+
+    back = meta.read_reference_metadata(path)
+    assert back.to_dict() == reference.to_dict()
+
+
+def test_reference_metadata_h5(tmp_path, reference):
+    path = tmp_path / "test.h5"
 
-    # check that we can write this to the header of a typical table file in multiple
-    # formats:
-    from astropy.table import Table  # pylint: disable=import-outside-toplevel
+    with tables.open_file(path, "w") as f:
+        meta.write_to_hdf5(reference.to_dict(), f)
 
-    table = Table(dict(x=[1, 2, 3], y=[15.2, 15.2, 14.5]))
-    for path in [tmp_path / "test.fits", tmp_path / "test.ecsv"]:
-        if ".fits" in path.suffixes:
-            reference.format = "fits"
-            ref_dict = reference.to_dict(fits=True)
-        else:
-            reference.format = "ecsv"
-            ref_dict = reference.to_dict()
+    back = meta.read_reference_metadata(path)
+    assert back.to_dict() == reference.to_dict()
 
-        table.meta = ref_dict
-        table.write(path)
 
-    # write to pytables file
+def test_reference_metadata_ecsv(tmp_path, reference):
+    path = tmp_path / "test.ecsv"
 
-    import tables  # pylint: disable=import-outside-toplevel
+    t = Table({"a": [1, 2, 3], "b": [4, 5, 6]})
+    t.meta.update(reference.to_dict())
+    t.write(path)
 
-    with tables.open_file(tmp_path / "test.h5", mode="w") as h5file:
-        h5file.create_group(where="/", name="node")
-        meta.write_to_hdf5(ref_dict, h5file, path="/node")
+    back = meta.read_reference_metadata(path)
+    assert back.to_dict() == reference.to_dict()
 
 
-def test_read_metadata(tmp_path):
+def test_read_hdf5_metadata(tmp_path):
     # Testing one can read both a path as well as a PyTables file object
     filename = tmp_path / "test.h5"
     metadata_in = {"SOFTWARE": "ctapipe", "FOO": "BAR"}
@@ -86,49 +106,10 @@ def test_read_metadata(tmp_path):
         h5file.create_group(where="/node", name="subnode", createparents=True)
         meta.write_to_hdf5(metadata_in, h5file, path=metadata_path)
 
-    metadata_out = meta.read_metadata(filename, path=metadata_path)
+    metadata_out = meta.read_hdf5_metadata(filename, path=metadata_path)
     assert metadata_out == metadata_in
 
     with tables.open_file(filename, "r") as file:
-        metadata_out = meta.read_metadata(file, path=metadata_path)
+        metadata_out = meta.read_hdf5_metadata(file, path=metadata_path)
 
     assert metadata_out == metadata_in
-
-
-def test_from_dict():
-    prov = Provenance()
-    prov.start_activity("test")
-    prov.finish_activity()
-    prov_activity = prov.finished_activities[0]
-
-    reference = meta.Reference(
-        contact=meta.Contact(
-            name="Somebody",
-            email="a@b.com",
-            organization="CTA Consortium",
-        ),
-        product=meta.Product(
-            description="An Amazing Product",
-            creation_time="2020-10-11 15:23:31",
-            data_category="Sim",
-            data_levels=["DL1_IMAGES", "DL1_PARAMETERS"],
-            data_association="Subarray",
-            data_model_name="Unofficial DL1",
-            data_model_version="1.0",
-            data_model_url="https://example.org",
-            format="hdf5",
-        ),
-        process=meta.Process(type_="Simulation", subtype="Prod3b", id_="423442"),
-        activity=meta.Activity.from_provenance(prov_activity.provenance),
-        instrument=meta.Instrument(
-            site="CTA-North",
-            class_="Array",
-            type_="Layout H1B",
-            version="1.0",
-            id_="threshold",
-        ),
-    )
-
-    as_dict = reference.to_dict()
-    back = meta.Reference.from_dict(as_dict)
-    assert back.to_dict() == as_dict

From a8ff9e25700eacd757a78dfa84062e1ad918d9f2 Mon Sep 17 00:00:00 2001
From: Maximilian Linhoff <maximilian.linhoff@tu-dortmund.de>
Date: Thu, 18 Jul 2024 16:11:59 +0200
Subject: [PATCH 2/3] Load reference metadata for input and output files and
 store in provenance

---
 docs/changes/2598.feature.rst             |  2 ++
 src/ctapipe/core/provenance.py            | 30 ++++++++++++++++++--
 src/ctapipe/core/tests/test_provenance.py | 34 +++++++++++++++++------
 src/ctapipe/io/datawriter.py              |  2 +-
 src/ctapipe/io/hdf5merger.py              |  4 +--
 src/ctapipe/tools/dump_instrument.py      | 12 +++++---
 src/ctapipe/tools/merge.py                |  3 +-
 7 files changed, 67 insertions(+), 20 deletions(-)
 create mode 100644 docs/changes/2598.feature.rst

diff --git a/docs/changes/2598.feature.rst b/docs/changes/2598.feature.rst
new file mode 100644
index 00000000000..16f05623c72
--- /dev/null
+++ b/docs/changes/2598.feature.rst
@@ -0,0 +1,2 @@
+The provenance system now records the reference metadata
+of input and output files, if available.
diff --git a/src/ctapipe/core/provenance.py b/src/ctapipe/core/provenance.py
index 2dc6527af3a..b2018f06038 100644
--- a/src/ctapipe/core/provenance.py
+++ b/src/ctapipe/core/provenance.py
@@ -11,6 +11,7 @@
 import platform
 import sys
 import uuid
+import warnings
 from collections import UserList
 from contextlib import contextmanager
 from importlib import import_module
@@ -57,6 +58,10 @@ def get_module_version(name):
         return "not installed"
 
 
+class MissingReferenceMetadata(UserWarning):
+    """Warning raised if reference metadata could not be read from input file."""
+
+
 class Provenance(metaclass=Singleton):
     """
     Manage the provenance info for a stack of *activities*
@@ -251,13 +256,19 @@ def register_input(self, url, role=None):
         role: str
             role name that this input satisfies
         """
-        self._prov["input"].append(dict(url=url, role=role))
+        reference_meta = self._get_reference_meta(url=url)
+        self._prov["input"].append(
+            dict(url=url, role=role, reference_meta=reference_meta)
+        )
 
     def register_output(self, url, role=None):
         """
         Add a URL of a file to the list of outputs (can be a filename or full
         url, if no URL specifier is given, assume 'file://')
 
+        Should only be called once the file is finalized, so that reference metadata
+        can be read.
+
         Parameters
         ----------
         url: str
@@ -265,7 +276,10 @@ def register_output(self, url, role=None):
         role: str
             role name that this output satisfies
         """
-        self._prov["output"].append(dict(url=url, role=role))
+        reference_meta = self._get_reference_meta(url=url)
+        self._prov["output"].append(
+            dict(url=url, role=role, reference_meta=reference_meta)
+        )
 
     def register_config(self, config):
         """add a dictionary of configuration parameters to this activity"""
@@ -302,6 +316,18 @@ def sample_cpu_and_memory(self):
     def provenance(self):
         return self._prov
 
+    def _get_reference_meta(self, url):
+        # here to prevent circular imports / top-level cross-dependencies
+        from ..io.metadata import read_reference_metadata
+
+        try:
+            return read_reference_metadata(url).to_dict()
+        except Exception:
+            warnings.warn(
+                f"Could not read reference metadata for input file: {url}",
+                MissingReferenceMetadata,
+            )
+
 
 def _get_python_packages():
     def _sortkey(dist):
diff --git a/src/ctapipe/core/tests/test_provenance.py b/src/ctapipe/core/tests/test_provenance.py
index f34ff6d9c3a..465e11ba27e 100644
--- a/src/ctapipe/core/tests/test_provenance.py
+++ b/src/ctapipe/core/tests/test_provenance.py
@@ -4,6 +4,7 @@
 
 from ctapipe.core import Provenance
 from ctapipe.core.provenance import _ActivityProvenance
+from ctapipe.io.metadata import Reference
 
 
 @pytest.fixture
@@ -15,19 +16,18 @@ def provenance(monkeypatch):
     prov = Provenance()
     monkeypatch.setattr(prov, "_activities", [])
     monkeypatch.setattr(prov, "_finished_activities", [])
-
-    prov.start_activity("test1")
-    prov.add_input_file("input.txt")
-    prov.add_output_file("output.txt")
-    prov.start_activity("test2")
-    prov.add_input_file("input_a.txt")
-    prov.add_input_file("input_b.txt")
-    prov.finish_activity("test2")
-    prov.finish_activity("test1")
     return prov
 
 
 def test_provenance_activity_names(provenance):
+    provenance.start_activity("test1")
+    provenance.add_input_file("input.txt")
+    provenance.add_output_file("output.txt")
+    provenance.start_activity("test2")
+    provenance.add_input_file("input_a.txt")
+    provenance.add_input_file("input_b.txt")
+    provenance.finish_activity("test2")
+    provenance.finish_activity("test1")
     assert set(provenance.finished_activity_names) == {"test2", "test1"}
 
 
@@ -52,6 +52,8 @@ def test_provenence_contextmanager():
 
 
 def test_provenance_json(provenance: Provenance):
+    provenance.start_activity("test1")
+    provenance.finish_activity("test1")
     data = json.loads(provenance.as_json())
 
     activity = data[0]
@@ -60,3 +62,17 @@ def test_provenance_json(provenance: Provenance):
     packages = activity["system"]["python"].get("packages")
     assert isinstance(packages, list)
     assert any(p["name"] == "numpy" for p in packages)
+
+
+def test_provenance_input_reference_meta(provenance: Provenance, dl1_file):
+    provenance.start_activity("test1")
+    provenance.add_input_file(dl1_file, "events")
+    provenance.finish_activity("test1")
+    data = json.loads(provenance.as_json())
+
+    inputs = data[0]["input"]
+    assert len(inputs) == 1
+    input_meta = inputs[0]
+    assert "reference_meta" in input_meta
+    assert "CTA PRODUCT ID" in input_meta["reference_meta"]
+    Reference.from_dict(input_meta["reference_meta"])
diff --git a/src/ctapipe/io/datawriter.py b/src/ctapipe/io/datawriter.py
index d0f93905f66..3119bc96695 100644
--- a/src/ctapipe/io/datawriter.py
+++ b/src/ctapipe/io/datawriter.py
@@ -388,6 +388,7 @@ def finish(self):
 
         self._write_context_metadata_headers()
         self._writer.close()
+        PROV.add_output_file(str(self.output_path), role="DL1/Event")
 
     @property
     def datalevels(self):
@@ -432,7 +433,6 @@ def _setup_output_path(self):
                     ", use the `overwrite` option or choose another `output_path` "
                 )
         self.log.debug("output path: %s", self.output_path)
-        PROV.add_output_file(str(self.output_path), role="DL1/Event")
 
         # check that options make sense
         writable_things = [
diff --git a/src/ctapipe/io/hdf5merger.py b/src/ctapipe/io/hdf5merger.py
index 58b98a78070..95d0a8b6909 100644
--- a/src/ctapipe/io/hdf5merger.py
+++ b/src/ctapipe/io/hdf5merger.py
@@ -183,7 +183,6 @@ def __init__(self, output_path=None, **kwargs):
             mode="a" if appending else "w",
             filters=DEFAULT_FILTERS,
         )
-        Provenance().add_output_file(str(self.output_path))
 
         self.required_nodes = None
         self.data_model_version = None
@@ -247,7 +246,7 @@ def _update_meta(self):
 
     def _read_meta(self, h5file):
         try:
-            return metadata.read_reference_metadata_hdf5(h5file)
+            return metadata._read_reference_metadata_hdf5(h5file)
         except Exception:
             raise CannotMerge(
                 f"CTA Reference meta not found in input file: {h5file.filename}"
@@ -384,6 +383,7 @@ def __exit__(self, exc_type, exc_value, traceback):
     def close(self):
         if hasattr(self, "h5file"):
             self.h5file.close()
+        Provenance().add_output_file(str(self.output_path))
 
     def _append_subarray(self, other):
         # focal length choice doesn't matter here, set to equivalent so we don't get
diff --git a/src/ctapipe/tools/dump_instrument.py b/src/ctapipe/tools/dump_instrument.py
index 7f169acdefb..a3ad471696b 100644
--- a/src/ctapipe/tools/dump_instrument.py
+++ b/src/ctapipe/tools/dump_instrument.py
@@ -91,11 +91,15 @@ def write_camera_definitions(self):
 
             try:
                 geom_table.write(geom_filename, **args)
-                readout_table.write(readout_filename, **args)
                 Provenance().add_output_file(geom_filename, "CameraGeometry")
+            except OSError as err:
+                self.log.exception("couldn't write camera geometry because: %s", err)
+
+            try:
+                readout_table.write(readout_filename, **args)
                 Provenance().add_output_file(readout_filename, "CameraReadout")
             except OSError as err:
-                self.log.warning("couldn't write camera definition because: %s", err)
+                self.log.exception("couldn't write camera definition because: %s", err)
 
     def write_optics_descriptions(self):
         """writes out optics files for each telescope type"""
@@ -109,7 +113,7 @@ def write_optics_descriptions(self):
             tab.write(filename, **args)
             Provenance().add_output_file(filename, "OpticsDescription")
         except OSError as err:
-            self.log.warning(
+            self.log.exception(
                 "couldn't write optics description '%s' because: %s", filename, err
             )
 
@@ -123,7 +127,7 @@ def write_subarray_description(self):
             tab.write(filename, **args)
             Provenance().add_output_file(filename, "SubarrayDescription")
         except OSError as err:
-            self.log.warning(
+            self.log.exception(
                 "couldn't write subarray description '%s' because: %s", filename, err
             )
 
diff --git a/src/ctapipe/tools/merge.py b/src/ctapipe/tools/merge.py
index ba9daad1549..3665d504cd4 100644
--- a/src/ctapipe/tools/merge.py
+++ b/src/ctapipe/tools/merge.py
@@ -161,7 +161,7 @@ def setup(self):
             )
             sys.exit(1)
 
-        self.merger = HDF5Merger(parent=self)
+        self.merger = self.enter_context(HDF5Merger(parent=self))
         if self.merger.output_path in self.input_files:
             raise ToolConfigurationError(
                 "Output path contained in input files. Fix your configuration / cli arguments."
@@ -195,7 +195,6 @@ def finish(self):
         current_activity = Provenance().current_activity.provenance
         self.merger.meta.activity = meta.Activity.from_provenance(current_activity)
         meta.write_to_hdf5(self.merger.meta.to_dict(), self.merger.h5file)
-        self.merger.close()
 
 
 def main():

From 819dc8739f9fc025849f3ea3efce61115ec6c3e8 Mon Sep 17 00:00:00 2001
From: Maximilian Linhoff <maximilian.linhoff@tu-dortmund.de>
Date: Wed, 24 Jul 2024 14:35:58 +0200
Subject: [PATCH 3/3] Prevent some warnings for input files where we know that
 no reference metadata is available

---
 src/ctapipe/core/provenance.py      | 22 ++++++++++++++--------
 src/ctapipe/core/tool.py            |  2 +-
 src/ctapipe/io/simteleventsource.py |  6 +++++-
 src/ctapipe/reco/reconstructor.py   |  3 ++-
 src/ctapipe/reco/sklearn.py         |  3 ++-
 5 files changed, 24 insertions(+), 12 deletions(-)

diff --git a/src/ctapipe/core/provenance.py b/src/ctapipe/core/provenance.py
index b2018f06038..a8f602e127f 100644
--- a/src/ctapipe/core/provenance.py
+++ b/src/ctapipe/core/provenance.py
@@ -96,7 +96,7 @@ def _get_current_or_start_activity(self):
 
         return self.current_activity
 
-    def add_input_file(self, filename, role=None):
+    def add_input_file(self, filename, role=None, add_meta=True):
         """register an input to the current activity
 
         Parameters
@@ -107,14 +107,14 @@ def add_input_file(self, filename, role=None):
             role this input file satisfies (optional)
         """
         activity = self._get_current_or_start_activity()
-        activity.register_input(abspath(filename), role=role)
+        activity.register_input(abspath(filename), role=role, add_meta=add_meta)
         log.debug(
             "added input entity '%s' to activity: '%s'",
             filename,
             activity.name,
         )
 
-    def add_output_file(self, filename, role=None):
+    def add_output_file(self, filename, role=None, add_meta=True):
         """
         register an output to the current activity
 
@@ -127,7 +127,7 @@ def add_output_file(self, filename, role=None):
 
         """
         activity = self._get_current_or_start_activity()
-        activity.register_output(abspath(filename), role=role)
+        activity.register_output(abspath(filename), role=role, add_meta=add_meta)
         log.debug(
             "added output entity '%s' to activity: '%s'",
             filename,
@@ -244,7 +244,7 @@ def start(self):
         self._prov["start"].update(_sample_cpu_and_memory())
         self._prov["system"].update(_get_system_provenance())
 
-    def register_input(self, url, role=None):
+    def register_input(self, url, role=None, add_meta=True):
         """
         Add a URL of a file to the list of inputs (can be a filename or full
         url, if no URL specifier is given, assume 'file://')
@@ -255,13 +255,16 @@ def register_input(self, url, role=None):
             filename or url of input file
         role: str
             role name that this input satisfies
+        add_meta: bool
+            If true, try to load reference metadata from input file
+            and add to provenance.
         """
-        reference_meta = self._get_reference_meta(url=url)
+        reference_meta = self._get_reference_meta(url=url) if add_meta else None
         self._prov["input"].append(
             dict(url=url, role=role, reference_meta=reference_meta)
         )
 
-    def register_output(self, url, role=None):
+    def register_output(self, url, role=None, add_meta=True):
         """
         Add a URL of a file to the list of outputs (can be a filename or full
         url, if no URL specifier is given, assume 'file://')
@@ -275,8 +278,11 @@ def register_output(self, url, role=None):
             filename or url of output file
         role: str
             role name that this output satisfies
+        add_meta: bool
+            If true, try to load reference metadata from input file
+            and add to provenance.
         """
-        reference_meta = self._get_reference_meta(url=url)
+        reference_meta = self._get_reference_meta(url=url) if add_meta else None
         self._prov["output"].append(
             dict(url=url, role=role, reference_meta=reference_meta)
         )
diff --git a/src/ctapipe/core/tool.py b/src/ctapipe/core/tool.py
index e1f7c2e2746..3579ba3c1bd 100644
--- a/src/ctapipe/core/tool.py
+++ b/src/ctapipe/core/tool.py
@@ -283,7 +283,7 @@ def load_config_file(self, path: str | pathlib.Path) -> None:
             # fall back to traitlets.config.Application's implementation
             super().load_config_file(str(path))
 
-        Provenance().add_input_file(path, role="Tool Configuration")
+        Provenance().add_input_file(path, role="Tool Configuration", add_meta=False)
 
     def update_logging_config(self):
         """Update the configuration of loggers."""
diff --git a/src/ctapipe/io/simteleventsource.py b/src/ctapipe/io/simteleventsource.py
index e4ff831dacb..cf89b11b461 100644
--- a/src/ctapipe/io/simteleventsource.py
+++ b/src/ctapipe/io/simteleventsource.py
@@ -345,8 +345,12 @@ def read_atmosphere_profile_from_simtel(
 
     if isinstance(simtelfile, str | Path):
         context_manager = SimTelFile(simtelfile)
+        # FIXME: simtel files currently do not have CTAO reference
+        # metadata, should be set to True once we store metadata
         Provenance().add_input_file(
-            filename=simtelfile, role="ctapipe.atmosphere.AtmosphereDensityProfile"
+            filename=simtelfile,
+            role="ctapipe.atmosphere.AtmosphereDensityProfile",
+            add_meta=False,
         )
 
     else:
diff --git a/src/ctapipe/reco/reconstructor.py b/src/ctapipe/reco/reconstructor.py
index 24b708e9d4a..d09c7d4b362 100644
--- a/src/ctapipe/reco/reconstructor.py
+++ b/src/ctapipe/reco/reconstructor.py
@@ -150,7 +150,8 @@ def read(cls, path, parent=None, subarray=None, **kwargs):
         for attr, value in kwargs.items():
             setattr(instance, attr, value)
 
-        Provenance().add_input_file(path, role="reconstructor")
+        # FIXME: we currently don't store metadata in the joblib / pickle files, see #2603
+        Provenance().add_input_file(path, role="reconstructor", add_meta=False)
         return instance
 
 
diff --git a/src/ctapipe/reco/sklearn.py b/src/ctapipe/reco/sklearn.py
index 6b6c9cc133f..19655dc1a0c 100644
--- a/src/ctapipe/reco/sklearn.py
+++ b/src/ctapipe/reco/sklearn.py
@@ -670,7 +670,8 @@ def read(cls, path, **kwargs):
                 f"{path} did not contain an instance of {cls}, got {instance}"
             )
 
-        Provenance().add_input_file(path, role="ml-models")
+        # FIXME: we currently don't store metadata in the joblib / pickle files, see #2603
+        Provenance().add_input_file(path, role="ml-models", add_meta=False)
         return instance
 
     @lazyproperty