diff --git a/src/dolphin/io/_paths.py b/src/dolphin/io/_paths.py
index e9f9c064..ad002751 100644
--- a/src/dolphin/io/_paths.py
+++ b/src/dolphin/io/_paths.py
@@ -67,12 +67,13 @@ def __init__(self, s3_url: Union[str, "S3Path"], unsigned: bool = False):
             self.path: Path = s3_url.path
             self._trailing_slash: str = s3_url._trailing_slash
         else:
-            parsed: ParseResult = urlparse(s3_url)
+            s = str(s3_url).strip()
+            parsed: ParseResult = urlparse(str(s))
             self._scheme = parsed.scheme
             self._netloc = self.bucket = parsed.netloc
             self._parsed = parsed
             self.path = Path(parsed.path)
-            self._trailing_slash = "/" if s3_url.endswith("/") else ""
+            self._trailing_slash = "/" if s.endswith("/") else ""
 
         if self._scheme != "s3":
             raise ValueError(f"{s3_url} is not an S3 url")
@@ -119,7 +120,7 @@ def parent(self):
     def suffix(self):
         return self.path.suffix
 
-    def resolve(self) -> S3Path:
+    def resolve(self, strict: bool = False) -> S3Path:
         """Resolve the path to an absolute path- S3 paths are always absolute."""
         return self
 
diff --git a/src/dolphin/workflows/config/_common.py b/src/dolphin/workflows/config/_common.py
index d0b72d45..960987a4 100644
--- a/src/dolphin/workflows/config/_common.py
+++ b/src/dolphin/workflows/config/_common.py
@@ -17,7 +17,7 @@
 from dolphin import __version__ as _dolphin_version
 from dolphin._log import get_log
 from dolphin._types import Bbox
-from dolphin.io import DEFAULT_HDF5_OPTIONS, DEFAULT_TIFF_OPTIONS
+from dolphin.io import DEFAULT_HDF5_OPTIONS, DEFAULT_TIFF_OPTIONS, S3Path
 
 from ._enums import ShpMethod, UnwrapMethod
 from ._yaml_model import YamlModel
@@ -518,4 +518,10 @@ def _read_file_list_or_glob(cls, value):  # noqa: ARG001:
             msg = f"Input file list {v_path} does not exist or is not a file."
             raise ValueError(msg)
 
-    return list(value)
+    out = []
+    for v in list(value):
+        try:
+            out.append(S3Path(v))
+        except ValueError:
+            out.append(Path(v))
+    return out
diff --git a/src/dolphin/workflows/config/_displacement.py b/src/dolphin/workflows/config/_displacement.py
index 494cf6e4..35f22e28 100644
--- a/src/dolphin/workflows/config/_displacement.py
+++ b/src/dolphin/workflows/config/_displacement.py
@@ -8,13 +8,16 @@
     BaseModel,
     ConfigDict,
     Field,
+    PlainSerializer,
     StringConstraints,
+    WithJsonSchema,
     field_validator,
     model_validator,
 )
 
 from dolphin._log import get_log
-from dolphin._types import TropoModel, TropoType
+from dolphin._types import GeneralPath, TropoModel, TropoType
+from dolphin.io import S3Path
 
 from ._common import (
     InputOptions,
@@ -98,18 +101,30 @@ def _to_empty_list(cls, v):
         return v if v is not None else []
 
 
+CslcFileList = Annotated[
+    # Any Path-like object is acceptable
+    list[GeneralPath],
+    # All Paths will be serialized to strings:
+    PlainSerializer(lambda x: [str(f) for f in x]),
+    # Let Pydantic know what the JSON Schema should be for this custom protocol:
+    # https://docs.pydantic.dev/latest/concepts/json_schema/#withjsonschema-annotation
+    WithJsonSchema({"type": "array", "items": {"type": "string", "format": "uri"}}),
+]
+
+
 class DisplacementWorkflow(WorkflowBase):
     """Configuration for the workflow."""
 
     # Paths to input/output files
     input_options: InputOptions = Field(default_factory=InputOptions)
-    cslc_file_list: list[Path] = Field(
+    cslc_file_list: CslcFileList = Field(
         default_factory=list,
         description=(
             "list of CSLC files, or newline-delimited file "
             "containing list of CSLC files."
         ),
     )
+
     output_options: OutputOptions = Field(default_factory=OutputOptions)
 
     # Options for each step in the workflow
@@ -140,7 +155,9 @@ class DisplacementWorkflow(WorkflowBase):
     # internal helpers
     # Stores the list of directories to be created by the workflow
     model_config = ConfigDict(
-        extra="allow", json_schema_extra={"required": ["cslc_file_list"]}
+        extra="allow",
+        json_schema_extra={"required": ["cslc_file_list"]},
+        arbitrary_types_allowed=True,
     )
 
     # validators
@@ -159,7 +176,7 @@ def _check_input_files_exist(self) -> DisplacementWorkflow:
         input_options = self.input_options
         date_fmt = input_options.cslc_date_fmt
         # Filter out files that don't have dates in the filename
-        files_matching_date = [Path(f) for f in file_list if get_dates(f, fmt=date_fmt)]
+        files_matching_date = [f for f in file_list if get_dates(f, fmt=date_fmt)]
         if len(files_matching_date) < len(file_list):
             msg = (
                 f"Found {len(files_matching_date)} files with dates like {date_fmt} in"
@@ -176,9 +193,13 @@ def _check_input_files_exist(self) -> DisplacementWorkflow:
                 raise ValueError(msg)
 
         # Coerce the file_list to a sorted list of Path objects
-        self.cslc_file_list = [
-            Path(f) for f in sort_files_by_date(file_list, file_date_fmt=date_fmt)[0]
-        ]
+        out: list[S3Path | Path] = []
+        for f in sort_files_by_date(file_list, file_date_fmt=date_fmt)[0]:
+            try:
+                out.append(S3Path(f))
+            except ValueError:
+                out.append(Path(f))
+        self.cslc_file_list = out
 
         return self