diff --git a/mmif/utils/cli/__init__.py b/mmif/utils/cli/__init__.py
index 77f6b74b..24855994 100644
--- a/mmif/utils/cli/__init__.py
+++ b/mmif/utils/cli/__init__.py
@@ -1,3 +1,4 @@
+from mmif.utils.cli import describe
 from mmif.utils.cli import rewind
 from mmif.utils.cli import source
 
diff --git a/mmif/utils/cli/describe.py b/mmif/utils/cli/describe.py
new file mode 100644
index 00000000..ab95205d
--- /dev/null
+++ b/mmif/utils/cli/describe.py
@@ -0,0 +1,333 @@
+import argparse
+import hashlib
+import json
+import sys
+import textwrap
+from pathlib import Path
+from typing import Union, List, Tuple, Optional
+
+from mmif import Mmif
+
+
+def split_appname_appversion(
+    long_app_id: str
+) -> Tuple[Optional[str], Optional[str]]:
+    """
+    Split app name and version from a long app identifier.
+
+    Assumes the identifier looks like "uri://APP_DOMAIN/APP_NAME/APP_VERSION"
+
+    :param long_app_id: Full app identifier URI
+    :return: Tuple of (app_name, app_version), either may be None if not found
+    """
+    app_path = Path(long_app_id).parts
+    app_name = app_path[2] if len(app_path) > 2 else None
+    app_version = app_path[3] if len(app_path) > 3 else None
+    if (app_version is not None and app_name is not None
+            and app_name.endswith(app_version)):
+        app_name = app_name[:-len(app_version) - 1]
+    if app_version == 'unresolvable':
+        app_version = None
+    return app_name, app_version
+
+
+def generate_param_hash(params: dict) -> str:
+    """
+    Generate MD5 hash from a parameter dictionary.
+
+    Parameters are sorted alphabetically, joined as key=value pairs,
+    and hashed using MD5. This is not for security purposes, only for
+    generating consistent identifiers.
+
+    :param params: Dictionary of parameters
+    :return: MD5 hash string (32 hex characters)
+    """
+    if not params:
+        param_string = ""
+    else:
+        param_list = ['='.join([k, str(v)]) for k, v in params.items()]
+        param_list.sort()
+        param_string = ','.join(param_list)
+    return hashlib.md5(param_string.encode('utf-8')).hexdigest()
+
+
+def get_pipeline_specs(
+    mmif_file: Union[str, Path]
+) -> Tuple[
+    List[Tuple[str, Optional[str], dict, Optional[str], Optional[dict], int, dict]],
+    List[str], List[str], List[str]
+]:
+    """
+    Read a MMIF file and extract the pipeline specification from it.
+
+    Extracts app configurations, profiling data, and annotation statistics
+    for each contentful view. Views with errors, warnings, or no annotations
+    are tracked separately.
+
+    :param mmif_file: Path to the MMIF file
+    :return: Tuple of (spec_list, error_views, warning_views, empty_views)
+             where spec_list contains tuples of (view_id, app_name, configs,
+             running_time_ms, running_hardware, annotation_count,
+             annotations_by_type) for each contentful view, and the three
+             lists contain view IDs for error/warning/empty views respectively
+    """
+    if not isinstance(mmif_file, (str, Path)):
+        raise ValueError(
+            "MMIF file path must be a string or a Path object."
+        )
+
+    with open(mmif_file, "r") as f:
+        mmif_str = f.read()
+
+    data = Mmif(mmif_str)
+    spec = []
+    error_views = []
+    warning_views = []
+    empty_views = []
+
+    for view in data.views:
+        # Track error, warning, and empty views (mutually exclusive)
+        if view.has_error():
+            error_views.append(view.id)
+            continue
+        elif view.has_warnings():
+            warning_views.append(view.id)
+            continue
+        elif len(view.annotations) == 0:
+            empty_views.append(view.id)
+            continue
+
+        app = view.metadata.get("app")
+        configs = view.metadata.get("appConfiguration", {})
+
+        # Get running time string (H:MM:SS.microseconds format)
+        # Support both new (appProfiling.runningTime) and old (appRunningTime)
+        running_time = None
+        if "appProfiling" in view.metadata:
+            profiling = view.metadata["appProfiling"]
+            if isinstance(profiling, dict) and "runningTime" in profiling:
+                running_time = profiling["runningTime"]
+        elif "appRunningTime" in view.metadata:
+            running_time = view.metadata["appRunningTime"]
+
+        # Support both new (appProfiling.hardware) and old (appRunningHardware)
+        running_hardware = None
+        if "appProfiling" in view.metadata:
+            profiling = view.metadata["appProfiling"]
+            if isinstance(profiling, dict) and "hardware" in profiling:
+                running_hardware = profiling["hardware"]
+        elif "appRunningHardware" in view.metadata:
+            running_hardware = view.metadata["appRunningHardware"]
+
+        # Count annotations and group by type
+        annotation_count = len(view.annotations)
+        annotations_by_type = {}
+        for annotation in view.annotations:
+            at_type = str(annotation.at_type)
+            annotations_by_type[at_type] = annotations_by_type.get(
+                at_type, 0
+            ) + 1
+
+        spec.append((
+            view.id, app, configs, running_time, running_hardware,
+            annotation_count, annotations_by_type
+        ))
+
+    return spec, error_views, warning_views, empty_views
+
+
+def generate_pipeline_identifier(mmif_file: Union[str, Path]) -> str:
+    """
+    Generate a pipeline identifier string from a MMIF file.
+
+    The identifier follows the storage directory structure format:
+    app_name/version/param_hash/app_name2/version2/param_hash2/...
+
+    Uses view.metadata.parameters (raw user-passed values) for hashing
+    to ensure reproducibility. Views with errors or warnings are excluded
+    from the identifier; empty views (no annotations) are included.
+
+    :param mmif_file: Path to the MMIF file
+    :return: Pipeline identifier string
+    """
+    if not isinstance(mmif_file, (str, Path)):
+        raise ValueError(
+            "MMIF file path must be a string or a Path object."
+        )
+
+    with open(mmif_file, "r") as f:
+        mmif_str = f.read()
+
+    data = Mmif(mmif_str)
+    segments = []
+
+    for view in data.views:
+        # Skip views with errors or warnings
+        if view.has_error() or view.has_warnings():
+            continue
+
+        app = view.metadata.get("app")
+        if app is None:
+            continue
+        app_name, app_version = split_appname_appversion(app)
+
+        # Use raw parameters for reproducibility
+        try:
+            param_dict = view.metadata.parameters
+        except (KeyError, AttributeError):
+            param_dict = {}
+
+        param_hash = generate_param_hash(param_dict)
+
+        # Build segment: app_name/version/hash
+        name_str = app_name if app_name else "unknown"
+        version_str = app_version if app_version else "unversioned"
+        segments.append(f"{name_str}/{version_str}/{param_hash}")
+
+    return '/'.join(segments)
+
+
+def describe_argparser():
+    """
+    Returns two strings: one-line description of the argparser, and
+    additional material, which will be shown in `clams --help` and
+    `clams <subcmd> --help`, respectively.
+    """
+    oneliner = (
+        'provides CLI to describe the pipeline specification from a MMIF '
+        'file.'
+    )
+    additional = textwrap.dedent("""
+    MMIF describe extracts pipeline information from a MMIF file and outputs
+    a JSON summary including:
+
+    - pipeline_id: unique identifier for the pipeline based on apps, versions,
+      and parameter hashes (excludes error/warning views)
+    - stats: annotation counts (total and per-view), counts by annotation type,
+      and lists of error/warning/empty view IDs
+    - views: map of view IDs to app configurations and profiling data
+
+    Views with errors or warnings are tracked but excluded from the pipeline
+    identifier and annotation statistics.""")
+    return oneliner, oneliner + '\n\n' + additional
+
+
+def prep_argparser(**kwargs):
+    parser = argparse.ArgumentParser(
+        description=describe_argparser()[1],
+        formatter_class=argparse.RawDescriptionHelpFormatter,
+        **kwargs
+    )
+    parser.add_argument(
+        "MMIF_FILE",
+        nargs="?",
+        type=argparse.FileType("r"),
+        default=None if sys.stdin.isatty() else sys.stdin,
+        help='input MMIF file path, or STDIN if `-` or not provided.'
+    )
+    parser.add_argument(
+        "-o", "--output",
+        type=argparse.FileType("w"),
+        default=sys.stdout,
+        help='output file path, or STDOUT if not provided.'
+    )
+    parser.add_argument(
+        "-p", "--pretty",
+        action="store_true",
+        help="Pretty-print JSON output"
+    )
+    return parser
+
+
+def main(args):
+    """
+    Main entry point for the describe CLI command.
+
+    Reads a MMIF file and outputs a JSON summary containing:
+    - pipeline_id: unique identifier for the pipeline
+    - stats: view counts, annotation counts (total/per-view/per-type),
+      and lists of error/warning/empty view IDs
+    - views: map of view IDs to app configurations and profiling data
+
+    :param args: Parsed command-line arguments
+    """
+    # Read MMIF content
+    mmif_content = args.MMIF_FILE.read()
+
+    # For file input, we need to handle the path
+    # If input is from stdin, create a temp file
+    import tempfile
+    with tempfile.NamedTemporaryFile(
+        mode='w', suffix='.mmif', delete=False
+    ) as tmp:
+        tmp.write(mmif_content)
+        tmp_path = tmp.name
+
+    try:
+        spec, error_views, warning_views, empty_views = get_pipeline_specs(
+            tmp_path
+        )
+        pipeline_id = generate_pipeline_identifier(tmp_path)
+
+        # Convert to JSON-serializable format and calculate stats
+        views = {}
+        annotation_count_stats = {"total": 0}
+        annotation_count_by_type = {}
+
+        for (view_id, app, configs, running_time, running_hardware,
+             annotation_count, annotations_by_type) in spec:
+            entry = {
+                "app": app,
+                "appConfiguration": configs,
+            }
+            # Output in new appProfiling format
+            if running_time is not None or running_hardware is not None:
+                profiling = {}
+                if running_time is not None:
+                    profiling["runningTime"] = running_time
+                if running_hardware is not None:
+                    profiling["hardware"] = running_hardware
+                entry["appProfiling"] = profiling
+
+            views[view_id] = entry
+
+            # Build annotation count stats
+            annotation_count_stats["total"] += annotation_count
+            annotation_count_stats[view_id] = annotation_count
+
+            # Build annotation count by type stats
+            for at_type, count in annotations_by_type.items():
+                if at_type not in annotation_count_by_type:
+                    annotation_count_by_type[at_type] = {"total": 0}
+                annotation_count_by_type[at_type]["total"] += count
+                annotation_count_by_type[at_type][view_id] = count
+
+        output = {
+            "pipeline_id": pipeline_id,
+            "stats": {
+                "viewCount": len(views),
+                "errorViews": error_views,
+                "warningViews": warning_views,
+                "emptyViews": empty_views,
+                "annotationCount": annotation_count_stats,
+                "annotationCountByType": annotation_count_by_type
+            },
+            "views": views
+        }
+
+        # Write output
+        if args.pretty:
+            json.dump(output, args.output, indent=2)
+        else:
+            json.dump(output, args.output)
+        args.output.write('\n')
+    finally:
+        # Clean up temp file
+        import os
+        os.unlink(tmp_path)
+
+
+if __name__ == "__main__":
+    parser = prep_argparser()
+    args = parser.parse_args()
+    main(args)
diff --git a/mmif/utils/cli/rewind.py b/mmif/utils/cli/rewind.py
index 570b0893..e5bd4ed3 100644
--- a/mmif/utils/cli/rewind.py
+++ b/mmif/utils/cli/rewind.py
@@ -76,14 +76,14 @@ def describe_argparser():
 def prep_argparser(**kwargs):
     parser = argparse.ArgumentParser(description=describe_argparser()[1], 
                                      formatter_class=argparse.RawDescriptionHelpFormatter, **kwargs)
-    parser.add_argument("IN_MMIF_FILE",
+    parser.add_argument("MMIF_FILE",
                         nargs="?", type=argparse.FileType("r"),
                         default=None if sys.stdin.isatty() else sys.stdin,
                         help='input MMIF file path, or STDIN if `-` or not provided.')
-    parser.add_argument("OUT_MMIF_FILE",
-                        nargs="?", type=argparse.FileType("w"),
+    parser.add_argument("-o", "--output",
+                        type=argparse.FileType("w"),
                         default=sys.stdout,
-                        help='output MMIF file path, or STDOUT if `-` or not provided.')
+                        help='output file path, or STDOUT if not provided.')
     parser.add_argument("-p", '--pretty', action='store_true', 
                         help="Pretty-print rewound MMIF")
     parser.add_argument("-n", '--number', default="0", type=int,
@@ -95,7 +95,7 @@ def prep_argparser(**kwargs):
 
 
 def main(args):
-    mmif_obj = mmif.Mmif(args.IN_MMIF_FILE.read())
+    mmif_obj = mmif.Mmif(args.MMIF_FILE.read())
 
     if args.number == 0:  # If user doesn't know how many views to rewind, give them choices.
         choice = prompt_user(mmif_obj)
@@ -104,7 +104,7 @@ def main(args):
     if not isinstance(choice, int) or choice <= 0:
         raise ValueError(f"Only can rewind by a positive number of views. Got {choice}.")
 
-    args.OUT_MMIF_FILE.write(rewind_mmif(mmif_obj, choice, args.mode == 'view').serialize(pretty=args.pretty))
+    args.output.write(rewind_mmif(mmif_obj, choice, args.mode == 'view').serialize(pretty=args.pretty))
 
 
 if __name__ == "__main__":
diff --git a/mmif/utils/cli/source.py b/mmif/utils/cli/source.py
index 7e662f9f..1e6b6b1b 100644
--- a/mmif/utils/cli/source.py
+++ b/mmif/utils/cli/source.py
@@ -258,10 +258,9 @@ def prep_argparser(**kwargs):
     )
     parser.add_argument(
         '-o', '--output',
-        default=None,
-        action='store',
-        nargs='?',
-        help='A name of a file to capture a generated MMIF json. When not given, MMIF is printed to stdout.'
+        type=argparse.FileType('w'),
+        default=sys.stdout,
+        help='output file path, or STDOUT if not provided.'
     )
     scheme_help = 'A scheme to associate with the document location URI. When not given, the default scheme is `file://`.'
     if len(discovered_docloc_plugins) > 0:
@@ -279,12 +278,8 @@ def prep_argparser(**kwargs):
 
 
 def main(args):
-    if args.output:
-        out_f = open(args.output, 'w')
-    else:
-        out_f = sys.stdout
     mmif = generate_source_mmif_from_file(windows_path=False, **vars(args))
-    out_f.write(mmif)
+    args.output.write(mmif)
     return mmif
 
 if __name__ == '__main__':
diff --git a/tests/test_utils_cli.py b/tests/test_utils_cli.py
index adb8e857..32f4c8bc 100644
--- a/tests/test_utils_cli.py
+++ b/tests/test_utils_cli.py
@@ -44,11 +44,11 @@ def get_params(self):
         return params
 
     def generate_source_mmif(self):
-        
-        # to suppress output (otherwise, set to stdout by default
+
+        # to suppress output (otherwise, set to stdout by default)
         args = self.parser.parse_args(self.get_params())
-        args.output = os.devnull
-        
+        args.output = open(os.devnull, 'w')
+
         return source.main(args)
 
     def test_accept_file_paths(self):