diff --git a/specs/cli/formatting.md b/specs/cli/formatting.md
new file mode 100644
index 0000000..9d0f9ee
--- /dev/null
+++ b/specs/cli/formatting.md
@@ -0,0 +1,218 @@
+# CLI: Output Formatting Enhancements
+
+## Overview
+
+Create a centralized `cli/formatting.py` module with reusable output helpers that replace the duplicated patterns currently scattered across CLI modules. This improves consistency, reduces code duplication, and prepares for richer output (progress indicators, table formatting).
+
+## Problem Statement
+
+The current CLI modules exhibit several repeated patterns:
+
+1. **Duplicated `_write()` helper** — Identical implementations in `manifest.py`, `tag.py`, `catalog.py`, and `referrer.py`.
+2. **Duplicated `_emit_error()` helper** — Nearly identical `click.echo(f"Error [{ref}]: {reason}", err=True)` + `sys.exit(code)` across all modules, with minor format variations in `auth.py` and `ping.py`.
+3. **Inconsistent JSON formatting** — Most modules use `json.dumps(obj, indent=2)`, but the pattern is manually applied everywhere.
+4. **No progress indicators** — Long-running operations (blob upload, layout push) provide no feedback.
+5. **No structured table output** — List commands (`tag list`, `catalog list`, `referrer list`) use raw `"\n".join()` or hand-crafted space-separated columns.
+
+## API Surface
+
+### Module: `src/regshape/cli/formatting.py`
+
+All output helpers live in a single module. No classes — just functions.
+
+---
+
+#### `emit_json(data: dict | list, output_path: str | None = None) -> None`
+
+Format and emit a JSON object. Always uses 2-space indentation.
+
+**Parameters:**
+- `data` — Serializable dict or list.
+- `output_path` — If provided, write to file instead of stdout.
+
+**Behavior:**
+- Calls `json.dumps(data, indent=2)`.
+- If `output_path` is set, writes to file (appending `\n` if missing), otherwise `click.echo()` to stdout.
+
+---
+
+#### `emit_text(content: str, output_path: str | None = None) -> None`
+
+Emit plain text content to stdout or a file.
+
+**Parameters:**
+- `content` — Text string to output.
+- `output_path` — If provided, write to file instead of stdout.
+
+**Behavior:**
+- If `output_path` is set, writes to file (appending `\n` if missing), otherwise `click.echo()` to stdout.
+
+This replaces the four duplicated `_write()` functions.
+
+---
+
+#### `emit_error(reference: str, reason: str, exit_code: int = 1) -> None`
+
+Print a standardized error message to stderr and exit.
+
+**Parameters:**
+- `reference` — Context identifier (image ref, registry, repo). Displayed in brackets.
+- `reason` — Human-readable error description.
+- `exit_code` — Process exit code (default: 1).
+
+**Output format:**
+```
+Error [registry/repo:tag]: manifest not found
+```
+
+**Behavior:**
+- `click.echo(f"Error [{reference}]: {reason}", err=True)`
+- `sys.exit(exit_code)`
+
+---
+
+#### `emit_table(rows: list[list[str]], headers: list[str] | None = None) -> None`
+
+Print tabular data with aligned columns.
+
+**Parameters:**
+- `rows` — List of row data, each row a list of string values.
+- `headers` — Optional column headers. When provided, printed first as a header row.
+
+**Behavior:**
+- Calculates column widths from the maximum length in each column (including headers).
+- Left-aligns all columns with 2-space padding between them.
+- Writes to stdout via `click.echo()`.
+
+**Example output (with headers):**
+```
+DIGEST                            ARTIFACT TYPE                    SIZE
+sha256:abc123...                  application/vnd.example+json     1024
+sha256:def456...                  application/vnd.other+json       2048
+```
+
+**Example output (without headers):**
+```
+sha256:abc123...  application/vnd.example+json  1024
+sha256:def456...  application/vnd.other+json    2048
+```
+
+---
+
+#### `emit_list(items: list[str], output_path: str | None = None) -> None`
+
+Print a simple one-item-per-line list.
+
+**Parameters:**
+- `items` — List of string items.
+- `output_path` — If provided, write to file instead of stdout.
+
+**Behavior:**
+- Joins items with `"\n"` and emits via `emit_text()`.
+- Replaces inline `"\n".join(...)` patterns in `tag list` and `catalog list`.
+
+---
+
+#### `format_key_value(pairs: list[tuple[str, str]], separator: str = ":") -> str`
+
+Format aligned key-value pairs for display (used by `manifest info`).
+
+**Parameters:**
+- `pairs` — List of `(key, value)` tuples.
+- `separator` — Character between key and value (default: `":"`).
+
+**Returns:** Formatted multi-line string with left-aligned keys and a vertically aligned separator.
+
+**Example:**
+```
+Digest      : sha256:abc123...
+Media Type  : application/vnd.oci.image.manifest.v1+json
+Size        : 1234
+```
+
+---
+
+#### `progress_status(message: str) -> None`
+
+Print a transient status message to stderr for long-running operations.
+
+**Parameters:**
+- `message` — Status message to display.
+
+**Behavior:**
+- Writes to stderr (`err=True`) so it doesn't interfere with piped stdout.
+- Uses `click.echo(message, err=True)`.
+
+**Usage in CLI commands:**
+```python
+from regshape.cli.formatting import progress_status
+
+progress_status("Uploading blob...")
+result = upload_blob(client, repo, file_path)
+progress_status("Upload complete.")
+```
+
+---
+
+## Migration Plan
+
+### Phase 1: Create `formatting.py` with all helpers
+
+Create the module with the functions defined above. Add unit tests.
+
+### Phase 2: Migrate existing CLI modules
+
+Replace duplicated code in each CLI module one at a time:
+
+| Module | Change |
+|--------|--------|
+| `manifest.py` | Replace `_write()` with `emit_text()` / `emit_json()`; replace `_emit_error()` with `emit_error()` |
+| `tag.py` | Replace `_write()` with `emit_text()` / `emit_list()`; replace `_emit_error()` with `emit_error()` |
+| `catalog.py` | Replace `_write()` with `emit_text()` / `emit_list()`; replace `_emit_error()` with `emit_error()` |
+| `referrer.py` | Replace `_write()` with `emit_text()`; replace `_emit_error()` with `emit_error()`; use `emit_table()` for list output |
+| `blob.py` | Replace `_emit_error()` with `emit_error()` |
+| `ping.py` | Replace inline error echoing with `emit_error()` |
+| `auth.py` | Replace `_emit_error()` with `emit_error()` |
+| `layout.py` | Replace inline progress messages with `progress_status()`; replace `_emit_error()` with `emit_error()` |
+| `docker.py` | Replace `_emit_error()` with `emit_error()` |
+
+### Phase 3: Add tests
+
+Create `src/regshape/tests/test_formatting.py` covering:
+
+- `emit_json` — Verifies correct JSON structure and file output.
+- `emit_text` — Verifies stdout and file output with newline handling.
+- `emit_error` — Verifies stderr output format and `sys.exit()` call.
+- `emit_table` — Verifies column alignment with and without headers.
+- `emit_list` — Verifies newline-joined output.
+- `format_key_value` — Verifies aligned key-value output.
+- `progress_status` — Verifies output goes to stderr.
+
+## Design Decisions
+
+### Why plain functions, not a class?
+
+The formatting helpers are stateless utilities. A class would add ceremony without benefit. Individual functions are easier to import selectively and test independently.
+
+### Why no third-party table library (e.g., `tabulate`, `rich`)?
+
+The project convention is to keep dependencies minimal (`click`, `requests`, `pytest` only). The table formatting needed is simple enough to implement with basic string operations. A third-party library can be considered later if requirements grow.
+
+### Why `progress_status()` instead of spinners/progress bars?
+
+Click does provide `click.progressbar()`, but the current blob upload and layout push operations don't expose a byte-level progress callback. Simple status messages to stderr are sufficient for now and don't require refactoring the operation layer. This can be enhanced later when streaming upload progress is available.
+
+### Why `emit_error()` calls `sys.exit()`?
+
+This matches the existing pattern where `_emit_error()` always exits. Keeping the exit in the helper reduces the chance of forgetting to exit after an error. Commands that need to handle errors without exiting can use `click.echo(..., err=True)` directly.
+
+## Dependencies
+
+- **Internal:** `click` (already a project dependency)
+- **External:** None (no new dependencies)
+
+## Open Questions
+
+- [ ] Should `emit_table()` support right-aligned numeric columns? (Current proposal: all left-aligned for simplicity.)
+- [ ] Should `progress_status()` use `\r` for overwriting the same line, or print sequential lines? (Current proposal: sequential lines.)
+- [ ] Should `emit_error()` accept an optional `--json` flag to output errors as JSON objects? (Some tools do this for machine-parseable error reporting.)
diff --git a/src/regshape/cli/auth.py b/src/regshape/cli/auth.py
index 3e00009..9022cf5 100644
--- a/src/regshape/cli/auth.py
+++ b/src/regshape/cli/auth.py
@@ -12,11 +12,10 @@
 .. moduleauthor:: ToddySM <toddysm@gmail.com>
 """
 
-import sys
-
 import click
 import requests
 
+from regshape.cli.formatting import emit_error
 from regshape.libs.auth.credentials import erase_credentials, resolve_credentials, store_credentials
 from regshape.libs.decorators import telemetry_options
 from regshape.libs.decorators.scenario import track_scenario
@@ -102,11 +101,9 @@ def login(ctx, registry, username, password, password_stdin, docker_config):
     try:
         _verify_credentials(registry, resolved_username, resolved_password, insecure=insecure)
     except AuthError as e:
-        _error(registry, str(e))
-        sys.exit(1)
+        emit_error(registry, str(e))
     except requests.exceptions.RequestException as e:
-        _error(registry, str(e))
-        sys.exit(1)
+        emit_error(registry, str(e))
 
     # --- Persist credentials ------------------------------------------------
     try:
@@ -117,8 +114,7 @@ def login(ctx, registry, username, password, password_stdin, docker_config):
             docker_config_path=docker_config,
         )
     except AuthError as e:
-        _error(registry, f"Could not store credentials: {e}")
-        sys.exit(1)
+        emit_error(registry, f"Could not store credentials: {e}")
 
     # --- Success output ------------------------------------------------------
     click.echo("Login succeeded.")
@@ -144,8 +140,7 @@ def logout(ctx, registry, docker_config):
     try:
         found = erase_credentials(registry, docker_config_path=docker_config)
     except AuthError as e:
-        _error(registry, str(e))
-        sys.exit(1)
+        emit_error(registry, str(e))
 
     if found:
         click.echo(f"Removing login credentials for {registry}.")
@@ -194,6 +189,3 @@ def _verify_credentials(registry: str, username: str, password: str, insecure: b
     )
 
 
-def _error(registry: str, reason: str) -> None:
-    """Print an error message to stderr."""
-    click.echo(f"Error for {registry}: {reason}", err=True)
diff --git a/src/regshape/cli/blob.py b/src/regshape/cli/blob.py
index 5182975..7c536c2 100644
--- a/src/regshape/cli/blob.py
+++ b/src/regshape/cli/blob.py
@@ -12,13 +12,10 @@
 .. moduleauthor:: ToddySM <toddysm@gmail.com>
 """
 
-import json
-import sys
-from typing import Optional
-
 import click
 import requests
 
+from regshape.cli.formatting import emit_error, emit_json
 from regshape.libs.blobs import (
     delete_blob,
     get_blob,
@@ -80,26 +77,23 @@ def blob_head(ctx, repo, digest):
     try:
         registry, repo_name, _ = parse_image_ref(repo)
     except ValueError as exc:
-        _error(repo, str(exc))
-        sys.exit(1)
+        emit_error(repo, str(exc))
 
     if repo.rstrip("/") != f"{registry}/{repo_name}":
-        _error(
+        emit_error(
             repo,
             "--repo must be a plain 'registry/repository' without tag or digest "
             "(e.g. ':tag' or '@sha256:...')",
         )
-        sys.exit(1)
 
     client = RegistryClient(TransportConfig(registry=registry, insecure=insecure))
 
     try:
         info = head_blob(client=client, repo=repo_name, digest=digest)
     except (AuthError, BlobError, requests.exceptions.RequestException) as exc:
-        _error(f"{repo}@{digest}", str(exc))
-        sys.exit(1)
+        emit_error(f"{repo}@{digest}", str(exc))
 
-    click.echo(json.dumps(info.to_dict(), indent=2))
+    emit_json(info.to_dict())
 
 
 # ===========================================================================
@@ -161,15 +155,13 @@ def blob_get(ctx, repo, digest, output, chunk_size):
         # Compare the reconstructed plain form against the raw input: any qualifier
         # (including ":latest") will cause a mismatch.
         if repo.rstrip("/") != f"{registry}/{repo_name}":
-            _error(
+            emit_error(
                 repo,
                 "--repo must be a plain 'registry/repository' without tag or digest "
                 "(e.g. ':tag' or '@sha256:...')",
             )
-            sys.exit(1)
     except ValueError as exc:
-        _error(repo, str(exc))
-        sys.exit(1)
+        emit_error(repo, str(exc))
 
     client = RegistryClient(TransportConfig(registry=registry, insecure=insecure))
 
@@ -182,10 +174,9 @@ def blob_get(ctx, repo, digest, output, chunk_size):
             chunk_size=chunk_size,
         )
     except (AuthError, BlobError, requests.exceptions.RequestException) as exc:
-        _error(f"{repo}@{digest}", str(exc))
-        sys.exit(1)
+        emit_error(f"{repo}@{digest}", str(exc))
 
-    click.echo(json.dumps(info.to_dict(), indent=2))
+    emit_json(info.to_dict())
 
 
 # ===========================================================================
@@ -225,23 +216,20 @@ def blob_delete(ctx, repo, digest):
     try:
         registry, repo_name, _ = parse_image_ref(repo)
     except ValueError as exc:
-        _error(repo, str(exc))
-        sys.exit(1)
+        emit_error(repo, str(exc))
 
     if repo.rstrip("/") != f"{registry}/{repo_name}":
-        _error(repo, "--repo must be a plain 'registry/repository' without tag or digest "
+        emit_error(repo, "--repo must be a plain 'registry/repository' without tag or digest "
                "(e.g. ':tag' or '@sha256:...')")
-        sys.exit(1)
 
     client = RegistryClient(TransportConfig(registry=registry, insecure=insecure))
 
     try:
         delete_blob(client=client, repo=repo_name, digest=digest)
     except (AuthError, BlobError, requests.exceptions.RequestException) as exc:
-        _error(f"{repo}@{digest}", str(exc))
-        sys.exit(1)
+        emit_error(f"{repo}@{digest}", str(exc))
 
-    click.echo(json.dumps({"digest": digest, "status": "deleted"}, indent=2))
+    emit_json({"digest": digest, "status": "deleted"})
 
 
 # ===========================================================================
@@ -312,12 +300,10 @@ def blob_upload(ctx, repo, source_file, digest, media_type, chunked, chunk_size)
     try:
         registry, repo_name, _ = parse_image_ref(repo)
     except ValueError as exc:
-        _error(repo, str(exc))
-        sys.exit(1)
+        emit_error(repo, str(exc))
 
     if repo.rstrip("/") != f"{registry}/{repo_name}":
-        _error(repo, "Repository must be a plain 'registry/repository' without a tag or digest")
-        sys.exit(1)
+        emit_error(repo, "Repository must be a plain 'registry/repository' without a tag or digest")
     client = RegistryClient(TransportConfig(registry=registry, insecure=insecure))
 
     try:
@@ -342,11 +328,9 @@ def blob_upload(ctx, repo, source_file, digest, media_type, chunked, chunk_size)
                 content_type=media_type,
             )
     except OSError as exc:
-        _error(source_file, str(exc))
-        sys.exit(1)
+        emit_error(source_file, str(exc))
     except (AuthError, BlobError, requests.exceptions.RequestException) as exc:
-        _error(f"{repo}@{digest}", str(exc))
-        sys.exit(1)
+        emit_error(f"{repo}@{digest}", str(exc))
 
     # Derive a canonical blob location from the confirmed digest.
     location = f"/v2/{repo_name}/blobs/{confirmed}"
@@ -355,11 +339,8 @@ def blob_upload(ctx, repo, source_file, digest, media_type, chunked, chunk_size)
     except OSError:
         size = 0
 
-    click.echo(
-        json.dumps(
-            {"digest": confirmed, "size": size, "location": location},
-            indent=2,
-        )
+    emit_json(
+        {"digest": confirmed, "size": size, "location": location}
     )
 
 
@@ -405,12 +386,10 @@ def blob_mount(ctx, repo, digest, from_repo):
     try:
         registry, repo_name, _ = parse_image_ref(repo)
     except ValueError as exc:
-        _error(repo, str(exc))
-        sys.exit(1)
+        emit_error(repo, str(exc))
 
     if repo.rstrip("/") != f"{registry}/{repo_name}":
-        _error(repo, "repository must be a plain 'registry/repo' without tag or digest")
-        sys.exit(1)
+        emit_error(repo, "repository must be a plain 'registry/repo' without tag or digest")
     client = RegistryClient(TransportConfig(registry=registry, insecure=insecure))
 
     try:
@@ -421,15 +400,11 @@ def blob_mount(ctx, repo, digest, from_repo):
             from_repo=from_repo,
         )
     except (AuthError, BlobError, requests.exceptions.RequestException) as exc:
-        _error(f"{repo}@{digest}", str(exc))
-        sys.exit(1)
+        emit_error(f"{repo}@{digest}", str(exc))
 
     location = f"/v2/{repo_name}/blobs/{confirmed}"
-    click.echo(
-        json.dumps(
-            {"digest": confirmed, "status": "mounted", "location": location},
-            indent=2,
-        )
+    emit_json(
+        {"digest": confirmed, "status": "mounted", "location": location}
     )
 
 
@@ -438,10 +413,6 @@ def blob_mount(ctx, repo, digest, from_repo):
 # ===========================================================================
 
 
-def _error(reference: str, reason: str) -> None:
-    """Print an error message to stderr, prefixed with the reference."""
-    click.echo(f"Error [{reference}]: {reason}", err=True)
-
 
 def _file_size(path: str) -> int:
     """Return the byte size of *path*."""
diff --git a/src/regshape/cli/catalog.py b/src/regshape/cli/catalog.py
index a64a254..a10dff1 100644
--- a/src/regshape/cli/catalog.py
+++ b/src/regshape/cli/catalog.py
@@ -12,13 +12,10 @@
 .. moduleauthor:: ToddySM <toddysm@gmail.com>
 """
 
-import json
-import sys
-from typing import Optional
-
 import click
 import requests
 
+from regshape.cli.formatting import emit_error, emit_json, emit_list
 from regshape.libs.catalog import list_catalog, list_catalog_all
 from regshape.libs.decorators import telemetry_options
 from regshape.libs.decorators.scenario import track_scenario
@@ -107,8 +104,7 @@ def catalog_list(ctx, registry, page_size, last, fetch_all, as_json, output):
     3=registry does not support the catalog API.
     """
     if fetch_all and last:
-        _error(registry, "--all and --last are mutually exclusive")
-        sys.exit(2)
+        emit_error(registry, "--all and --last are mutually exclusive", exit_code=2)
 
     insecure = ctx.obj.get("insecure", False) if ctx.obj else False
     client = RegistryClient(TransportConfig(registry=registry, insecure=insecure))
@@ -119,37 +115,18 @@ def catalog_list(ctx, registry, page_size, last, fetch_all, as_json, output):
         else:
             result = list_catalog(client, page_size=page_size, last=last)
     except CatalogNotSupportedError as exc:
-        _error(registry, str(exc))
-        sys.exit(3)
+        emit_error(registry, str(exc), exit_code=3)
     except (AuthError, CatalogError, requests.exceptions.RequestException) as exc:
-        _error(registry, str(exc))
-        sys.exit(1)
+        emit_error(registry, str(exc))
 
     if as_json:
-        _write(output, json.dumps(result.to_dict(), indent=2))
+        emit_json(result.to_dict(), output)
     else:
-        _write(output, "\n".join(result.repositories))
+        emit_list(result.repositories, output)
 
 
 # ===========================================================================
 # Internal helpers — output and error
 # ===========================================================================
 
-def _write(output_path: Optional[str], content: str) -> None:
-    """Write *content* to a file or stdout.
-
-    :param output_path: File path, or ``None`` to write to stdout.
-    :param content: Text to write.
-    """
-    if output_path:
-        with open(output_path, "w", encoding="utf-8") as fh:
-            fh.write(content)
-            if not content.endswith("\n"):
-                fh.write("\n")
-    else:
-        click.echo(content)
-
 
-def _error(reference: str, reason: str) -> None:
-    """Print an error message to stderr, prefixed with the reference."""
-    click.echo(f"Error [{reference}]: {reason}", err=True)
diff --git a/src/regshape/cli/docker.py b/src/regshape/cli/docker.py
index a61adf9..71797be 100644
--- a/src/regshape/cli/docker.py
+++ b/src/regshape/cli/docker.py
@@ -12,11 +12,9 @@
 .. moduleauthor:: ToddySM <toddysm@gmail.com>
 """
 
-import json
-import sys
-
 import click
 
+from regshape.cli.formatting import emit_error, emit_json
 from regshape.libs.docker import export_image, list_images, push_image
 from regshape.libs.errors import AuthError, BlobError, DockerError, LayoutError, ManifestError
 
@@ -37,10 +35,6 @@ def _format_size(size_bytes: int) -> str:
     return f"{size_bytes}B"
 
 
-def _error(context: str, reason: str) -> None:
-    """Print an error message to stderr."""
-    click.echo(f"Error [{context}]: {reason}", err=True)
-
 
 # ===========================================================================
 # Public Click group
@@ -72,8 +66,7 @@ def list_cmd(ctx, name_filter, as_json):
     try:
         images = list_images(name_filter=name_filter)
     except DockerError as exc:
-        _error("docker list", str(exc))
-        sys.exit(1)
+        emit_error("docker list", str(exc))
 
     if as_json:
         output = [
@@ -88,7 +81,7 @@ def list_cmd(ctx, name_filter, as_json):
             }
             for img in images
         ]
-        click.echo(json.dumps(output, indent=2))
+        emit_json(output)
     else:
         if not images:
             click.echo("No images found.")
@@ -154,8 +147,7 @@ def export_cmd(ctx, image, output, platform, as_json):
     try:
         export_image(image, output, platform=platform)
     except (DockerError, LayoutError) as exc:
-        _error("docker export", str(exc))
-        sys.exit(1)
+        emit_error("docker export", str(exc))
 
     if as_json:
         result = {
@@ -164,7 +156,7 @@ def export_cmd(ctx, image, output, platform, as_json):
         }
         if platform:
             result["platform"] = platform
-        click.echo(json.dumps(result, indent=2))
+        emit_json(result)
     else:
         msg = f"Exported {image} to OCI layout at {output}"
         if platform:
@@ -232,8 +224,7 @@ def push_cmd(ctx, image, dest, platform, force, chunked, chunk_size, as_json):
             chunk_size=chunk_size,
         )
     except (DockerError, LayoutError, AuthError, BlobError, ManifestError) as exc:
-        _error("docker push", str(exc))
-        sys.exit(1)
+        emit_error("docker push", str(exc))
 
     if as_json:
         output = {
@@ -249,7 +240,7 @@ def push_cmd(ctx, image, dest, platform, force, chunked, chunk_size, as_json):
         }
         if platform:
             output["platform"] = platform
-        click.echo(json.dumps(output, indent=2))
+        emit_json(output)
     else:
         total_manifests = len(result.manifests)
         total_uploaded = sum(
diff --git a/src/regshape/cli/formatting.py b/src/regshape/cli/formatting.py
new file mode 100644
index 0000000..8924d67
--- /dev/null
+++ b/src/regshape/cli/formatting.py
@@ -0,0 +1,124 @@
+#!/usr/bin/env python3
+
+"""
+:mod:`regshape.cli.formatting` - Reusable CLI output formatting helpers
+========================================================================
+
+.. module:: regshape.cli.formatting
+   :platform: Unix, Windows
+   :synopsis: Centralized output helpers for JSON, text, error messages,
+              tables, lists, key-value pairs, and progress status.
+
+.. moduleauthor:: ToddySM <toddysm@gmail.com>
+"""
+
+import json
+import sys
+from typing import Optional
+
+import click
+
+
+def emit_json(data: dict | list, output_path: Optional[str] = None, err: bool = False) -> None:
+    """Format and emit a JSON object with 2-space indentation.
+
+    :param data: Serializable dict or list.
+    :param output_path: If provided, write to file instead of stdout.
+    :param err: If ``True``, write to stderr instead of stdout.
+    """
+    content = json.dumps(data, indent=2)
+    emit_text(content, output_path, err=err)
+
+
+def emit_text(content: str, output_path: Optional[str] = None, err: bool = False) -> None:
+    """Emit plain text content to stdout or a file.
+
+    :param content: Text string to output.
+    :param output_path: If provided, write to file instead of stdout.
+    :param err: If ``True``, write to stderr instead of stdout (ignored
+        when *output_path* is set).
+    """
+    if output_path:
+        with open(output_path, "w", encoding="utf-8") as fh:
+            fh.write(content)
+            if not content.endswith("\n"):
+                fh.write("\n")
+    else:
+        click.echo(content, err=err)
+
+
+def emit_error(reference: str, reason: str, exit_code: int = 1) -> None:
+    """Print a standardized error message to stderr and exit.
+
+    :param reference: Context identifier displayed in brackets.
+    :param reason: Human-readable error description.
+    :param exit_code: Process exit code (default: 1).
+    """
+    click.echo(f"Error [{reference}]: {reason}", err=True)
+    sys.exit(exit_code)
+
+
+def emit_table(rows: list[list[str]], headers: Optional[list[str]] = None) -> None:
+    """Print tabular data with aligned columns.
+
+    :param rows: List of row data, each row a list of string values.
+    :param headers: Optional column headers.
+    """
+    all_rows = ([headers] + rows) if headers else rows
+    if not all_rows:
+        return
+
+    num_cols = max(len(row) for row in all_rows)
+    col_widths = [0] * num_cols
+    for row in all_rows:
+        for i, cell in enumerate(row):
+            col_widths[i] = max(col_widths[i], len(cell))
+
+    def _format_row(row: list[str]) -> str:
+        parts = []
+        for i, cell in enumerate(row):
+            if i < len(col_widths):
+                parts.append(cell.ljust(col_widths[i]))
+            else:
+                parts.append(cell)
+        return "  ".join(parts).rstrip()
+
+    if headers:
+        click.echo(_format_row(headers))
+
+    for row in rows:
+        click.echo(_format_row(row))
+
+
+def emit_list(items: list[str], output_path: Optional[str] = None) -> None:
+    """Print a simple one-item-per-line list.
+
+    :param items: List of string items.
+    :param output_path: If provided, write to file instead of stdout.
+    """
+    emit_text("\n".join(items), output_path)
+
+
+def format_key_value(pairs: list[tuple[str, str]], separator: str = ":") -> str:
+    """Format aligned key-value pairs for display.
+
+    :param pairs: List of (key, value) tuples.
+    :param separator: Character between key and value (default: ``":"``).
+    :returns: Formatted multi-line string with aligned values.
+    """
+    if not pairs:
+        return ""
+    max_key_len = max(len(k) for k, _ in pairs)
+    lines = []
+    for key, value in pairs:
+        padded_key = key.ljust(max_key_len)
+        lines.append(f"{padded_key}{separator} {value}")
+    return "\n".join(lines)
+
+
+def progress_status(message: str) -> None:
+    """Print a transient status message to stderr.
+
+    :param message: Status message to display.
+    """
+    click.echo(message, err=True)
diff --git a/src/regshape/cli/layout.py b/src/regshape/cli/layout.py
index eab96d4..7c0fedf 100644
--- a/src/regshape/cli/layout.py
+++ b/src/regshape/cli/layout.py
@@ -22,6 +22,7 @@
 
 import click
 
+from regshape.cli.formatting import emit_error, emit_json, progress_status
 from regshape.libs.decorators import telemetry_options
 from regshape.libs.decorators.scenario import track_scenario
 from regshape.libs.errors import AuthError, BlobError, LayoutError, ManifestError
@@ -105,9 +106,6 @@ def _media_type_for_compression(compression: str) -> str:
     return OCI_IMAGE_LAYER_TAR_GZIP
 
 
-def _error(context: str, reason: str) -> None:
-    """Print an error message to stderr."""
-    click.echo(f"Error [{context}]: {reason}", err=True)
 
 
 # ===========================================================================
@@ -174,11 +172,10 @@ def init_cmd(ctx, layout_path, as_json):
     try:
         init_layout(layout_path)
     except (LayoutError, OSError) as exc:
-        _error(layout_path, str(exc))
-        sys.exit(1)
+        emit_error(layout_path, str(exc))
 
     if as_json:
-        click.echo(json.dumps({"layout_path": str(layout_path)}, indent=2))
+        emit_json({"layout_path": str(layout_path)})
     else:
         click.echo(f"Initialised OCI Image Layout at {layout_path}")
 
@@ -232,8 +229,7 @@ def add_layer(ctx, layout_path, layer_file, compress_format, media_type, raw_ann
         with open(layer_file, "rb") as fh:
             data = fh.read()
     except OSError as exc:
-        _error(layer_file, str(exc))
-        sys.exit(1)
+        emit_error(layer_file, str(exc))
 
     detected = _detect_compression(data)
 
@@ -259,8 +255,7 @@ def add_layer(ctx, layout_path, layer_file, compress_format, media_type, raw_ann
         annotations = _parse_annotations(raw_annotations) if raw_annotations else None
         descriptor = stage_layer(layout_path, data, media_type, annotations=annotations)
     except (LayoutError, OSError, click.BadParameter) as exc:
-        _error(layout_path, str(exc))
-        sys.exit(1)
+        emit_error(layout_path, str(exc))
 
     if as_json:
         out: dict = {
@@ -270,7 +265,7 @@ def add_layer(ctx, layout_path, layer_file, compress_format, media_type, raw_ann
         }
         if descriptor.annotations:
             out["annotations"] = descriptor.annotations
-        click.echo(json.dumps(out, indent=2))
+        emit_json(out)
     else:
         click.echo(f"Staged layer {descriptor.digest} ({descriptor.size} bytes)")
 
@@ -314,8 +309,7 @@ def annotate_layer(ctx, layout_path, layer_index, raw_annotations, replace, as_j
             layout_path, layer_index, annotations, replace=replace
         )
     except (LayoutError, OSError, click.BadParameter) as exc:
-        _error(layout_path, str(exc))
-        sys.exit(1)
+        emit_error(layout_path, str(exc))
 
     if as_json:
         out: dict = {
@@ -326,7 +320,7 @@ def annotate_layer(ctx, layout_path, layer_index, raw_annotations, replace, as_j
         }
         if descriptor.annotations:
             out["annotations"] = descriptor.annotations
-        click.echo(json.dumps(out, indent=2))
+        emit_json(out)
     else:
         click.echo(f"Updated layer {layer_index}: {descriptor.digest}")
 
@@ -361,14 +355,13 @@ def annotate_manifest_cmd(ctx, layout_path, raw_annotations, replace, as_json):
         annotations = _parse_annotations(raw_annotations)
         descriptor = update_manifest_annotations(layout_path, annotations, replace=replace)
     except (LayoutError, OSError, click.BadParameter) as exc:
-        _error(layout_path, str(exc))
-        sys.exit(1)
+        emit_error(layout_path, str(exc))
 
     if as_json:
         out: dict = {"digest": descriptor.digest, "size": descriptor.size}
         if descriptor.annotations:
             out["annotations"] = descriptor.annotations
-        click.echo(json.dumps(out, indent=2))
+        emit_json(out)
     else:
         click.echo(f"Updated manifest annotations: {descriptor.digest}")
 
@@ -434,8 +427,7 @@ def generate_config_cmd(
             annotations=annotations,
         )
     except (LayoutError, OSError, click.BadParameter) as exc:
-        _error(layout_path, str(exc))
-        sys.exit(1)
+        emit_error(layout_path, str(exc))
 
     if as_json:
         out: dict = {
@@ -445,7 +437,7 @@ def generate_config_cmd(
         }
         if descriptor.annotations:
             out["annotations"] = descriptor.annotations
-        click.echo(json.dumps(out, indent=2))
+        emit_json(out)
     else:
         click.echo(f"Generated config {descriptor.digest} ({descriptor.size} bytes)")
 
@@ -503,8 +495,7 @@ def generate_manifest_cmd(
             annotations=annotations,
         )
     except (LayoutError, OSError, click.BadParameter) as exc:
-        _error(layout_path, str(exc))
-        sys.exit(1)
+        emit_error(layout_path, str(exc))
 
     if as_json:
         out: dict = {
@@ -516,7 +507,7 @@ def generate_manifest_cmd(
             out["ref_name"] = ref_name
         if descriptor.annotations:
             out["annotations"] = descriptor.annotations
-        click.echo(json.dumps(out, indent=2))
+        emit_json(out)
     else:
         ref_str = f" [{ref_name}]" if ref_name else ""
         click.echo(
@@ -578,8 +569,7 @@ def update_config_cmd(
             replace_annotations=replace_annotations,
         )
     except (LayoutError, OSError, click.BadParameter) as exc:
-        _error(layout_path, str(exc))
-        sys.exit(1)
+        emit_error(layout_path, str(exc))
 
     # Warn when a manifest already exists (it will reference the old config digest)
     try:
@@ -595,7 +585,7 @@ def update_config_cmd(
                 "Manifest exists and references the old config digest; "
                 "regenerate or update it."
             )
-        click.echo(json.dumps(out, indent=2))
+        emit_json(out)
     else:
         click.echo(f"Updated config {descriptor.digest} ({descriptor.size} bytes)")
         if manifest_stale:
@@ -626,11 +616,10 @@ def status(ctx, layout_path, as_json):
     try:
         stage = read_stage(layout_path)
     except (LayoutError, OSError) as exc:
-        _error(layout_path, str(exc))
-        sys.exit(1)
+        emit_error(layout_path, str(exc))
 
     if as_json:
-        click.echo(json.dumps(stage, indent=2))
+        emit_json(stage)
     else:
         layers = stage.get("layers", [])
         config = stage.get("config")
@@ -674,10 +663,9 @@ def show(ctx, layout_path):
     try:
         index = read_index(layout_path)
     except (LayoutError, OSError) as exc:
-        _error(layout_path, str(exc))
-        sys.exit(1)
+        emit_error(layout_path, str(exc))
 
-    click.echo(json.dumps(json.loads(index.to_json()), indent=2))
+    emit_json(json.loads(index.to_json()))
 
 
 # ===========================================================================
@@ -707,8 +695,7 @@ def validate(ctx, layout_path):
     try:
         validate_layout(layout_path)
     except (LayoutError, OSError) as exc:
-        _error(layout_path, str(exc))
-        sys.exit(1)
+        emit_error(layout_path, str(exc))
 
     click.echo(f"Layout at {layout_path} is valid.")
 
@@ -794,8 +781,7 @@ def push_cmd(ctx, layout_path, dest, force, chunked, chunk_size, dry_run, as_jso
     try:
         registry, repo, reference = parse_image_ref(dest)
     except ValueError as exc:
-        _error(layout_path, str(exc))
-        sys.exit(1)
+        emit_error(layout_path, str(exc))
 
     tag_override = reference if reference != "latest" or _has_explicit_ref(dest) else None
 
@@ -827,8 +813,7 @@ def progress_callback(event, **kwargs):
                 # Immediately complete — we don't have per-byte callback from
                 # the library upload, so show as complete once done.
             else:
-                click.echo(f"  Uploading {_short_digest(digest)} ({_format_size(size)})...",
-                           err=True)
+                progress_status(f"  Uploading {_short_digest(digest)} ({_format_size(size)})...")
         elif event == "blob_done":
             if use_progress and current_bar[0] is not None:
                 bar = current_bar[0]
@@ -836,14 +821,12 @@ def progress_callback(event, **kwargs):
                 bar.__exit__(None, None, None)
                 current_bar[0] = None
             else:
-                click.echo(f"  Uploaded  {_short_digest(digest)}", err=True)
+                progress_status(f"  Uploaded  {_short_digest(digest)}")
         elif event == "blob_skip":
-            click.echo(f"  {_short_digest(digest)} ({_format_size(size)}) exists, skipping",
-                       err=True)
+            progress_status(f"  {_short_digest(digest)} ({_format_size(size)}) exists, skipping")
         elif event == "manifest_done":
             ref = kwargs.get("reference", "")
-            click.echo(f"  Manifest {_short_digest(digest)} -> {ref}  pushed",
-                       err=True)
+            progress_status(f"  Manifest {_short_digest(digest)} -> {ref}  pushed")
 
     # --- Execute push ---
     dest_display = f"{registry}/{repo}"
@@ -851,7 +834,7 @@ def progress_callback(event, **kwargs):
         dest_display += f":{tag_override}"
 
     if not as_json:
-        click.echo(f"Pushing layout {layout_path} -> {dest_display}\n", err=True)
+        progress_status(f"Pushing layout {layout_path} -> {dest_display}\n")
 
     try:
         result = push_layout(
@@ -865,11 +848,9 @@ def progress_callback(event, **kwargs):
             progress_callback=progress_callback,
         )
     except LayoutError as exc:
-        _error(layout_path, str(exc))
-        sys.exit(1)
+        emit_error(layout_path, str(exc))
     except (AuthError, BlobError, ManifestError) as exc:
-        _error(dest_display, str(exc))
-        sys.exit(1)
+        emit_error(dest_display, str(exc))
     finally:
         if current_bar[0] is not None:
             current_bar[0].__exit__(None, None, None)
@@ -905,13 +886,12 @@ def progress_callback(event, **kwargs):
                 "bytes_uploaded": result.bytes_uploaded,
             },
         }
-        click.echo(json.dumps(output, indent=2))
+        emit_json(output)
     else:
-        click.echo(
+        progress_status(
             f"\nPush complete: {result.manifests_pushed} manifest(s), "
             f"{result.blobs_uploaded} blob(s) uploaded, "
-            f"{result.blobs_skipped} blob(s) skipped.",
-            err=True,
+            f"{result.blobs_skipped} blob(s) skipped."
         )
 
 
@@ -924,20 +904,17 @@ def _push_dry_run(layout_path, registry, repo, tag_override, as_json):
         validate_layout(layout_path)
         index = read_index(layout_path)
     except LayoutError as exc:
-        _error(layout_path, str(exc))
-        sys.exit(1)
+        emit_error(layout_path, str(exc))
 
     if not index.manifests:
-        _error(layout_path, "index.json contains no manifests")
-        sys.exit(1)
+        emit_error(layout_path, "index.json contains no manifests")
 
     if tag_override and len(index.manifests) > 1:
-        _error(
+        emit_error(
             layout_path,
             f"tag override supplied but index.json has {len(index.manifests)} manifests; "
             "omit the tag or push a single-manifest layout",
         )
-        sys.exit(1)
 
     from regshape.libs.layout import read_blob as _rb
 
@@ -978,7 +955,7 @@ def _push_dry_run(layout_path, registry, repo, tag_override, as_json):
                 for entry, ref, blobs in results
             ],
         }
-        click.echo(json.dumps(output, indent=2))
+        emit_json(output)
     else:
         click.echo(f"[dry-run] Layout {layout_path} -> {registry}/{repo}\n")
         for entry, ref, blobs in results:
diff --git a/src/regshape/cli/manifest.py b/src/regshape/cli/manifest.py
index a1ac849..377c88c 100644
--- a/src/regshape/cli/manifest.py
+++ b/src/regshape/cli/manifest.py
@@ -15,18 +15,18 @@
 
 import json
 import sys
-from typing import Optional
 
 import click
 import requests
 
+from regshape.cli.formatting import emit_error, emit_json, emit_text, format_key_value
 from regshape.libs.decorators import telemetry_options
 from regshape.libs.decorators.scenario import track_scenario
 from regshape.libs.errors import AuthError, ManifestError
 from regshape.libs.manifests import delete_manifest, get_manifest, head_manifest, push_manifest
 from regshape.libs.models.manifest import ImageIndex, ImageManifest, parse_manifest
 from regshape.libs.models.mediatype import ALL_MANIFEST_MEDIA_TYPES, OCI_IMAGE_MANIFEST
-from regshape.libs.refs import format_ref, parse_image_ref
+from regshape.libs.refs import parse_image_ref
 from regshape.libs.transport import RegistryClient, TransportConfig
 
 # ---------------------------------------------------------------------------
@@ -119,8 +119,7 @@ def get(ctx, image_ref, accept, part, output, raw):
     try:
         registry, repo, reference = parse_image_ref(image_ref)
     except ValueError as exc:
-        _error(image_ref, str(exc))
-        sys.exit(1)
+        emit_error(image_ref, str(exc))
 
     client = RegistryClient(TransportConfig(registry=registry, insecure=insecure))
 
@@ -132,31 +131,27 @@ def get(ctx, image_ref, accept, part, output, raw):
             accept=accept or _DEFAULT_ACCEPT,
         )
     except (AuthError, ManifestError, requests.exceptions.RequestException) as exc:
-        _error(image_ref, str(exc))
-        sys.exit(1)
+        emit_error(image_ref, str(exc))
 
     if raw:
-        _write(output, body)
+        emit_text(body, output)
         return
 
     # Parse and optionally extract a specific field
     try:
         parsed = parse_manifest(body)
     except ManifestError as exc:
-        _error(image_ref, f"Failed to parse manifest: {exc}")
-        sys.exit(1)
+        emit_error(image_ref, f"Failed to parse manifest: {exc}")
 
     if part:
         exit_code, result = _extract_part(parsed, part)
         if exit_code != 0:
-            _error(image_ref, result)
-            sys.exit(exit_code)
-        _write(output, result)
+            emit_error(image_ref, result, exit_code)
+        emit_text(result, output)
         return
 
     # Full manifest output
-    manifest_dict = json.loads(parsed.to_json())
-    _write(output, json.dumps(manifest_dict, indent=2))
+    emit_json(json.loads(parsed.to_json()), output)
 
 
 # ===========================================================================
@@ -192,8 +187,7 @@ def info(ctx, image_ref, accept):
     try:
         registry, repo, reference = parse_image_ref(image_ref)
     except ValueError as exc:
-        _error(image_ref, str(exc))
-        sys.exit(1)
+        emit_error(image_ref, str(exc))
 
     client = RegistryClient(TransportConfig(registry=registry, insecure=insecure))
 
@@ -205,12 +199,13 @@ def info(ctx, image_ref, accept):
             accept=accept or _DEFAULT_ACCEPT,
         )
     except (AuthError, ManifestError, requests.exceptions.RequestException) as exc:
-        _error(image_ref, str(exc))
-        sys.exit(1)
+        emit_error(image_ref, str(exc))
 
-    click.echo(f"Digest:       {digest}")
-    click.echo(f"Media Type:   {media_type}")
-    click.echo(f"Size:         {size}")
+    click.echo(format_key_value([
+        ("Digest", digest),
+        ("Media Type", media_type),
+        ("Size", str(size)),
+    ]))
 
 
 # ===========================================================================
@@ -248,8 +243,7 @@ def descriptor(ctx, image_ref, accept):
     try:
         registry, repo, reference = parse_image_ref(image_ref)
     except ValueError as exc:
-        _error(image_ref, str(exc))
-        sys.exit(1)
+        emit_error(image_ref, str(exc))
 
     client = RegistryClient(TransportConfig(registry=registry, insecure=insecure))
 
@@ -261,14 +255,13 @@ def descriptor(ctx, image_ref, accept):
             accept=accept or _DEFAULT_ACCEPT,
         )
     except (AuthError, ManifestError, requests.exceptions.RequestException) as exc:
-        _error(image_ref, str(exc))
-        sys.exit(1)
+        emit_error(image_ref, str(exc))
 
-    click.echo(json.dumps({
+    emit_json({
         "mediaType": media_type,
         "digest": digest,
         "size": size,
-    }, indent=2))
+    })
 
 
 # ===========================================================================
@@ -328,8 +321,7 @@ def put(ctx, image_ref, manifest_file, from_stdin, content_type):
     try:
         registry, repo, reference = parse_image_ref(image_ref)
     except ValueError as exc:
-        _error(image_ref, str(exc))
-        sys.exit(1)
+        emit_error(image_ref, str(exc))
 
     # Read manifest body
     if manifest_file:
@@ -357,8 +349,7 @@ def put(ctx, image_ref, manifest_file, from_stdin, content_type):
             content_type=content_type,
         )
     except (AuthError, ManifestError, requests.exceptions.RequestException) as exc:
-        _error(image_ref, str(exc))
-        sys.exit(1)
+        emit_error(image_ref, str(exc))
 
     click.echo(f"Pushed: {digest}")
 
@@ -391,16 +382,15 @@ def delete(ctx, image_ref):
     try:
         registry, repo, reference = parse_image_ref(image_ref)
     except ValueError as exc:
-        _error(image_ref, str(exc))
-        sys.exit(1)
+        emit_error(image_ref, str(exc))
 
     if not reference.startswith("sha256:") and not reference.startswith("sha512:"):
-        _error(
+        emit_error(
             image_ref,
             "manifest delete requires a digest reference (@sha256:...); "
             "tag references are not supported by the OCI spec for delete operations",
+            exit_code=2,
         )
-        sys.exit(2)
 
     client = RegistryClient(TransportConfig(registry=registry, insecure=insecure))
 
@@ -411,8 +401,7 @@ def delete(ctx, image_ref):
             digest=reference,
         )
     except (AuthError, ManifestError, requests.exceptions.RequestException) as exc:
-        _error(image_ref, str(exc))
-        sys.exit(1)
+        emit_error(image_ref, str(exc))
 
     click.echo(f"Deleted: {reference}")
 
@@ -453,21 +442,4 @@ def _extract_part(
     return 1, f"unknown part: {part!r}"
 
 
-def _write(output_path: Optional[str], content: str) -> None:
-    """Write *content* to a file or stdout.
 
-    :param output_path: File path, or ``None`` to write to stdout.
-    :param content: Text to write.
-    """
-    if output_path:
-        with open(output_path, "w", encoding="utf-8") as fh:
-            fh.write(content)
-            if not content.endswith("\n"):
-                fh.write("\n")
-    else:
-        click.echo(content)
-
-
-def _error(reference: str, reason: str) -> None:
-    """Print an error message to stderr, prefixed with the image reference."""
-    click.echo(f"Error [{reference}]: {reason}", err=True)
diff --git a/src/regshape/cli/ping.py b/src/regshape/cli/ping.py
index 4e558a4..c6e8c87 100644
--- a/src/regshape/cli/ping.py
+++ b/src/regshape/cli/ping.py
@@ -12,12 +12,12 @@
 .. moduleauthor:: ToddySM <toddysm@gmail.com>
 """
 
-import json
 import sys
 
 import click
 import requests
 
+from regshape.cli.formatting import emit_json
 from regshape.libs.decorators import telemetry_options
 from regshape.libs.decorators.scenario import track_scenario
 from regshape.libs.errors import AuthError, PingError
@@ -65,14 +65,14 @@ def ping(ctx, registry, as_json):
         # A 401/403 during token negotiation means the registry *is*
         # reachable but requires credentials.  Report success with a hint.
         if as_json:
-            click.echo(json.dumps({
+            emit_json({
                 "registry": registry,
                 "reachable": True,
                 "api_version": None,
                 "latency_ms": None,
                 "note": "Registry requires authentication",
                 "error": str(exc),
-            }, indent=2))
+            })
         else:
             click.echo(f"Registry {registry} is reachable")
             click.echo("  Note: Registry requires authentication. "
@@ -86,25 +86,14 @@ def ping(ctx, registry, as_json):
         _error(registry, str(exc), as_json)
         sys.exit(1)
 
-        if as_json:
-            output = {
-                "registry": registry,
-                "reachable": False,
-                "status_code": result.status_code,
-                "api_version": result.api_version,
-                "latency_ms": result.latency_ms,
-                "error": f"HTTP {result.status_code}",
-            }
-            click.echo(json.dumps(output, indent=2), err=True)
-        else:
-            _error(registry, f"HTTP {result.status_code}", as_json)
+    if not result.reachable:
         _error(registry, f"HTTP {result.status_code}", as_json)
         sys.exit(1)
 
     if as_json:
         output = result.to_dict()
         output["registry"] = registry
-        click.echo(json.dumps(output, indent=2))
+        emit_json(output)
     else:
         click.echo(f"Registry {registry} is reachable")
         if result.api_version:
@@ -120,10 +109,10 @@ def ping(ctx, registry, as_json):
 def _error(registry: str, detail: str, as_json: bool = False) -> None:
     """Print an error message to stderr."""
     if as_json:
-        click.echo(json.dumps({
+        emit_json({
             "registry": registry,
             "reachable": False,
             "error": detail,
-        }, indent=2), err=True)
+        }, err=True)
     else:
         click.echo(f"Error: Registry {registry} is not reachable: {detail}", err=True)
diff --git a/src/regshape/cli/referrer.py b/src/regshape/cli/referrer.py
index 033ac92..d4f5b09 100644
--- a/src/regshape/cli/referrer.py
+++ b/src/regshape/cli/referrer.py
@@ -12,13 +12,10 @@
 .. moduleauthor:: ToddySM <toddysm@gmail.com>
 """
 
-import json
-import sys
-from typing import Optional
-
 import click
 import requests
 
+from regshape.cli.formatting import emit_error, emit_json, emit_table, emit_text
 from regshape.libs.decorators import telemetry_options
 from regshape.libs.decorators.scenario import track_scenario
 from regshape.libs.errors import AuthError, ReferrerError
@@ -103,18 +100,17 @@ def referrer_list(ctx, image_ref, artifact_type, fetch_all, as_json, output):
     try:
         registry, repo, reference = parse_image_ref(image_ref)
     except ValueError as exc:
-        _error(image_ref, str(exc))
-        sys.exit(1)
+        emit_error(image_ref, str(exc))
 
     # The referrers API requires a digest reference.
     if not reference.startswith("sha256:") and not reference.startswith("sha512:"):
-        _error(
+        emit_error(
             image_ref,
             "referrer list requires a digest reference "
             "(registry/repo@sha256:...); "
             "use 'manifest get' to resolve a tag to a digest",
+            exit_code=2,
         )
-        sys.exit(2)
 
     client = RegistryClient(TransportConfig(registry=registry, insecure=insecure))
 
@@ -134,38 +130,30 @@ def referrer_list(ctx, image_ref, artifact_type, fetch_all, as_json, output):
                 artifact_type=artifact_type,
             )
     except (AuthError, ReferrerError, requests.exceptions.RequestException) as exc:
-        _error(image_ref, str(exc))
-        sys.exit(1)
+        emit_error(image_ref, str(exc))
 
     if as_json:
-        _write(output, json.dumps(result.to_dict(), indent=2))
+        emit_json(result.to_dict(), output)
     else:
-        lines = [
-            f"{d.digest} {d.artifact_type or ''} {d.size}"
+        if not result.manifests:
+            if output:
+                # Ensure the output file is created even when there are no referrers
+                emit_text("", output)
+            return
+        rows = [
+            [d.digest, d.artifact_type or "", str(d.size)]
             for d in result.manifests
         ]
-        _write(output, "\n".join(lines))
+        if output:
+            # For file output, use space-separated columns
+            lines = [f"{r[0]} {r[1]} {r[2]}" for r in rows]
+            emit_text("\n".join(lines), output)
+        else:
+            emit_table(rows, headers=["DIGEST", "ARTIFACT TYPE", "SIZE"])
 
 
 # ===========================================================================
 # Internal helpers — output and error
 # ===========================================================================
 
-def _write(output_path: Optional[str], content: str) -> None:
-    """Write *content* to a file or stdout.
-
-    :param output_path: File path, or ``None`` to write to stdout.
-    :param content: Text to write.
-    """
-    if output_path:
-        with open(output_path, "w", encoding="utf-8") as fh:
-            fh.write(content)
-            if not content.endswith("\n"):
-                fh.write("\n")
-    else:
-        click.echo(content)
-
 
-def _error(reference: str, reason: str) -> None:
-    """Print an error message to stderr, prefixed with the reference."""
-    click.echo(f"Error [{reference}]: {reason}", err=True)
diff --git a/src/regshape/cli/tag.py b/src/regshape/cli/tag.py
index 3643e9d..2b5f6c7 100644
--- a/src/regshape/cli/tag.py
+++ b/src/regshape/cli/tag.py
@@ -12,13 +12,10 @@
 .. moduleauthor:: ToddySM <toddysm@gmail.com>
 """
 
-import json
-import sys
-from typing import Optional
-
 import click
 import requests
 
+from regshape.cli.formatting import emit_error, emit_json, emit_list, emit_text
 from regshape.libs.decorators import telemetry_options
 from regshape.libs.decorators.scenario import track_scenario
 from regshape.libs.errors import AuthError, TagError
@@ -104,8 +101,7 @@ def tag_list(ctx, image_ref, page_size, last, as_json, output):
     try:
         registry, repo, _ = parse_image_ref(image_ref)
     except ValueError as exc:
-        _error(image_ref, str(exc))
-        sys.exit(1)
+        emit_error(image_ref, str(exc))
 
     client = RegistryClient(TransportConfig(registry=registry, insecure=insecure))
 
@@ -117,13 +113,12 @@ def tag_list(ctx, image_ref, page_size, last, as_json, output):
             last=last,
         )
     except (AuthError, TagError, requests.exceptions.RequestException) as exc:
-        _error(image_ref, str(exc))
-        sys.exit(1)
+        emit_error(image_ref, str(exc))
 
     if as_json:
-        _write(output, json.dumps(tag_list.to_dict(), indent=2))
+        emit_json(tag_list.to_dict(), output)
     else:
-        _write(output, "\n".join(tag_list.tags))
+        emit_list(tag_list.tags, output)
 
 
 # ===========================================================================
@@ -159,16 +154,15 @@ def delete(ctx, image_ref):
     try:
         registry, repo, reference = parse_image_ref(image_ref)
     except ValueError as exc:
-        _error(image_ref, str(exc))
-        sys.exit(1)
+        emit_error(image_ref, str(exc))
 
     if reference.startswith("sha256:") or reference.startswith("sha512:"):
-        _error(
+        emit_error(
             image_ref,
             "tag delete requires a tag reference; "
             "use 'manifest delete' for digest references",
+            exit_code=2,
         )
-        sys.exit(2)
 
     client = RegistryClient(TransportConfig(registry=registry, insecure=insecure))
 
@@ -179,8 +173,7 @@ def delete(ctx, image_ref):
             tag=reference,
         )
     except (AuthError, TagError, requests.exceptions.RequestException) as exc:
-        _error(image_ref, str(exc))
-        sys.exit(1)
+        emit_error(image_ref, str(exc))
 
     click.echo(f"Deleted tag: {format_ref(registry, repo, reference)}")
 
@@ -189,21 +182,4 @@ def delete(ctx, image_ref):
 # Internal helpers — output and error
 # ===========================================================================
 
-def _write(output_path: Optional[str], content: str) -> None:
-    """Write *content* to a file or stdout.
-
-    :param output_path: File path, or ``None`` to write to stdout.
-    :param content: Text to write.
-    """
-    if output_path:
-        with open(output_path, "w", encoding="utf-8") as fh:
-            fh.write(content)
-            if not content.endswith("\n"):
-                fh.write("\n")
-    else:
-        click.echo(content)
-
 
-def _error(reference: str, reason: str) -> None:
-    """Print an error message to stderr, prefixed with the reference."""
-    click.echo(f"Error [{reference}]: {reason}", err=True)
diff --git a/src/regshape/tests/test_formatting.py b/src/regshape/tests/test_formatting.py
new file mode 100644
index 0000000..838bc2f
--- /dev/null
+++ b/src/regshape/tests/test_formatting.py
@@ -0,0 +1,202 @@
+#!/usr/bin/env python3
+
+"""Tests for :mod:`regshape.cli.formatting`."""
+
+import json
+
+import pytest
+
+from regshape.cli.formatting import (
+    emit_error,
+    emit_json,
+    emit_list,
+    emit_table,
+    emit_text,
+    format_key_value,
+    progress_status,
+)
+
+
+# ===========================================================================
+# emit_json
+# ===========================================================================
+
+
+class TestEmitJson:
+    def test_stdout(self, capsys):
+        emit_json({"key": "value", "num": 42})
+        captured = capsys.readouterr()
+        assert json.loads(captured.out) == {"key": "value", "num": 42}
+        # Verify 2-space indentation
+        assert '  "key"' in captured.out
+
+    def test_list(self, capsys):
+        emit_json([1, 2, 3])
+        captured = capsys.readouterr()
+        assert json.loads(captured.out) == [1, 2, 3]
+
+    def test_file_output(self, tmp_path):
+        out_file = str(tmp_path / "out.json")
+        emit_json({"a": 1}, output_path=out_file)
+        content = open(out_file).read()
+        assert json.loads(content) == {"a": 1}
+        assert content.endswith("\n")
+
+    def test_err_goes_to_stderr(self, capsys):
+        emit_json({"error": "fail"}, err=True)
+        captured = capsys.readouterr()
+        assert captured.out == ""
+        assert json.loads(captured.err) == {"error": "fail"}
+
+
+# ===========================================================================
+# emit_text
+# ===========================================================================
+
+
+class TestEmitText:
+    def test_stdout(self, capsys):
+        emit_text("hello world")
+        assert capsys.readouterr().out == "hello world\n"
+
+    def test_file_output(self, tmp_path):
+        out_file = str(tmp_path / "out.txt")
+        emit_text("hello", output_path=out_file)
+        assert open(out_file).read() == "hello\n"
+
+    def test_file_output_preserves_trailing_newline(self, tmp_path):
+        out_file = str(tmp_path / "out.txt")
+        emit_text("hello\n", output_path=out_file)
+        assert open(out_file).read() == "hello\n"
+
+    def test_err_goes_to_stderr(self, capsys):
+        emit_text("oops", err=True)
+        captured = capsys.readouterr()
+        assert captured.out == ""
+        assert "oops" in captured.err
+
+
+# ===========================================================================
+# emit_error
+# ===========================================================================
+
+
+class TestEmitError:
+    def test_format_and_exit(self, capsys):
+        with pytest.raises(SystemExit) as exc_info:
+            emit_error("registry/repo:tag", "manifest not found")
+        assert exc_info.value.code == 1
+        captured = capsys.readouterr()
+        assert captured.err == "Error [registry/repo:tag]: manifest not found\n"
+        assert captured.out == ""
+
+    def test_custom_exit_code(self, capsys):
+        with pytest.raises(SystemExit) as exc_info:
+            emit_error("ref", "bad input", exit_code=2)
+        assert exc_info.value.code == 2
+
+    def test_output_goes_to_stderr(self, capsys):
+        with pytest.raises(SystemExit):
+            emit_error("ctx", "reason")
+        captured = capsys.readouterr()
+        assert "Error [ctx]: reason" in captured.err
+        assert captured.out == ""
+
+
+# ===========================================================================
+# emit_table
+# ===========================================================================
+
+
+class TestEmitTable:
+    def test_with_headers(self, capsys):
+        emit_table(
+            [["sha256:abc", "sbom", "1024"], ["sha256:def", "sig", "2048"]],
+            headers=["DIGEST", "TYPE", "SIZE"],
+        )
+        out = capsys.readouterr().out
+        lines = out.strip().split("\n")
+        assert len(lines) == 3
+        assert "DIGEST" in lines[0]
+        assert "sha256:abc" in lines[1]
+        assert "sha256:def" in lines[2]
+
+    def test_without_headers(self, capsys):
+        emit_table([["a", "bb"], ["ccc", "d"]])
+        out = capsys.readouterr().out
+        lines = out.strip().split("\n")
+        assert len(lines) == 2
+
+    def test_column_alignment(self, capsys):
+        emit_table(
+            [["short", "x"], ["longer_value", "y"]],
+            headers=["COL1", "COL2"],
+        )
+        out = capsys.readouterr().out
+        lines = out.strip().split("\n")
+        # All values in col2 should start at the same column
+        second_col_values = ["COL2", "x", "y"]
+        col2_positions = [
+            line.index(value) for line, value in zip(lines, second_col_values)
+        ]
+        assert len(set(col2_positions)) == 1
+        assert len(lines) == 3
+
+    def test_empty_rows(self, capsys):
+        emit_table([])
+        assert capsys.readouterr().out == ""
+
+
+# ===========================================================================
+# emit_list
+# ===========================================================================
+
+
+class TestEmitList:
+    def test_stdout(self, capsys):
+        emit_list(["tag1", "tag2", "tag3"])
+        assert capsys.readouterr().out == "tag1\ntag2\ntag3\n"
+
+    def test_file_output(self, tmp_path):
+        out_file = str(tmp_path / "tags.txt")
+        emit_list(["a", "b"], output_path=out_file)
+        assert open(out_file).read() == "a\nb\n"
+
+
+# ===========================================================================
+# format_key_value
+# ===========================================================================
+
+
+class TestFormatKeyValue:
+    def test_basic_alignment(self):
+        result = format_key_value([
+            ("Digest", "sha256:abc"),
+            ("Media Type", "application/vnd.oci.image.manifest.v1+json"),
+            ("Size", "1234"),
+        ])
+        lines = result.split("\n")
+        assert len(lines) == 3
+        assert lines[0].startswith("Digest    :")
+        assert lines[1].startswith("Media Type:")
+        assert lines[2].startswith("Size      :")
+
+    def test_custom_separator(self):
+        result = format_key_value([("Key", "val")], separator="=")
+        assert result == "Key= val"
+
+    def test_empty(self):
+        assert format_key_value([]) == ""
+
+
+# ===========================================================================
+# progress_status
+# ===========================================================================
+
+
+class TestProgressStatus:
+    def test_output_to_stderr(self, capsys):
+        progress_status("Uploading blob...")
+        captured = capsys.readouterr()
+        assert "Uploading blob..." in captured.err
+        assert captured.out == ""
diff --git a/src/regshape/tests/test_manifest_cli.py b/src/regshape/tests/test_manifest_cli.py
index f1ff57e..6773bbb 100644
--- a/src/regshape/tests/test_manifest_cli.py
+++ b/src/regshape/tests/test_manifest_cli.py
@@ -269,9 +269,9 @@ def test_info_success_plain(self):
                 ["manifest", "info", "-i", f"{REGISTRY}/{REPO}:{TAG}"],
             )
         assert result.exit_code == 0, result.output
-        assert "Digest:" in result.output
+        assert "Digest" in result.output
         assert DIGEST in result.output
-        assert "Media Type:" in result.output
+        assert "Media Type" in result.output
 
     def test_info_404_exits_1(self):
         with patch("regshape.cli.manifest.head_manifest",