I have a PR that should fix this: https://github.com/bazelbuild/bazel/pull/17045

Cleanup progress when using bzlmod
Currently when using bzlmod your action's progress can look something like `@_main~bzlmod_tool_dependencies~Yams//:Yams`, in the past this would have been displayed as `@Yams//:Yams` and generally IMO this adds a lot of visual noise if you have many dependencies like this.
src/main/java/com/google/devtools/build/lib/actions/AbstractAction.java src/main/java/com/google/devtools/build/lib/actions/ActionExecutionMetadata.java src/main/java/com/google/devtools/build/lib/pkgcache/LoadingPhaseCompleteEvent.java src/main/java/com/google/devtools/build/lib/runtime/SkymeldUiStateTracker.java src/main/java/com/google/devtools/build/lib/runtime/UiStateTracker.java src/main/java/com/google/devtools/build/lib/skyframe/TargetPatternPhaseFunction.java
src/main/java/com/google/devtools/build/lib/actions/AbstractAction.java src/main/java/com/google/devtools/build/lib/actions/ActionExecutionMetadata.java src/main/java/com/google/devtools/build/lib/pkgcache/LoadingPhaseCompleteEvent.java src/main/java/com/google/devtools/build/lib/runtime/SkymeldUiStateTracker.java src/main/java/com/google/devtools/build/lib/runtime/UiStateTracker.java src/main/java/com/google/devtools/build/lib/skyframe/TargetPatternPhaseFunction.java
src/test/java/com/google/devtools/build/lib/runtime/SkymeldUiStateTrackerTest.java src/test/java/com/google/devtools/build/lib/runtime/UiStateTrackerTest.java
diff --git a/src/main/java/com/google/devtools/build/lib/actions/AbstractAction.java b/src/main/java/com/google/devtools/build/lib/actions/AbstractAction.java
index 262754415cf3cb..e76a72dcfedf13 100644
--- a/src/main/java/com/google/devtools/build/lib/actions/AbstractAction.java
+++ b/src/main/java/com/google/devtools/build/lib/actions/AbstractAction.java
@@ -27,6 +27,7 @@
 import com.google.devtools.build.lib.actions.extra.ExtraActionInfo;
 import com.google.devtools.build.lib.analysis.platform.PlatformInfo;
 import com.google.devtools.build.lib.cmdline.Label;
+import com.google.devtools.build.lib.cmdline.RepositoryMapping;
 import com.google.devtools.build.lib.collect.nestedset.Depset;
 import com.google.devtools.build.lib.collect.nestedset.NestedSet;
 import com.google.devtools.build.lib.collect.nestedset.NestedSetBuilder;
@@ -363,14 +364,47 @@ public boolean showsOutputUnconditionally() {
   @Nullable
   @Override
   public final String getProgressMessage() {
+    return getProgressMessageChecked(null);
+  }
+
+  @Nullable
+  @Override
+  public final String getProgressMessage(RepositoryMapping mainRepositoryMapping) {
+    Preconditions.checkNotNull(mainRepositoryMapping);
+    return getProgressMessageChecked(mainRepositoryMapping);
+  }
+
+  private String getProgressMessageChecked(@Nullable RepositoryMapping mainRepositoryMapping) {
     String message = getRawProgressMessage();
     if (message == null) {
       return null;
     }
+    message = replaceProgressMessagePlaceholders(message, mainRepositoryMapping);
     String additionalInfo = getOwner().getAdditionalProgressInfo();
     return additionalInfo == null ? message : message + " [" + additionalInfo + "]";
   }
 
+  private String replaceProgressMessagePlaceholders(
+      String progressMessage, @Nullable RepositoryMapping mainRepositoryMapping) {
+    if (progressMessage.contains("%{label}") && getOwner().getLabel() != null) {
+      String labelString;
+      if (mainRepositoryMapping != null) {
+        labelString = getOwner().getLabel().getDisplayForm(mainRepositoryMapping);
+      } else {
+        labelString = getOwner().getLabel().toString();
+      }
+      progressMessage = progressMessage.replace("%{label}", labelString);
+    }
+    if (progressMessage.contains("%{output}") && getPrimaryOutput() != null) {
+      progressMessage =
+          progressMessage.replace("%{output}", getPrimaryOutput().getExecPathString());
+    }
+    if (progressMessage.contains("%{input}") && getPrimaryInput() != null) {
+      progressMessage = progressMessage.replace("%{input}", getPrimaryInput().getExecPathString());
+    }
+    return progressMessage;
+  }
+
   /**
    * Returns a progress message string that is specific for this action. This is then annotated with
    * additional information, currently the string '[for tool]' for actions in the tool
diff --git a/src/main/java/com/google/devtools/build/lib/actions/ActionExecutionMetadata.java b/src/main/java/com/google/devtools/build/lib/actions/ActionExecutionMetadata.java
index 338fb06993fdbc..4d21092df79b82 100644
--- a/src/main/java/com/google/devtools/build/lib/actions/ActionExecutionMetadata.java
+++ b/src/main/java/com/google/devtools/build/lib/actions/ActionExecutionMetadata.java
@@ -13,6 +13,7 @@
 // limitations under the License.
 package com.google.devtools.build.lib.actions;
 
+import com.google.devtools.build.lib.cmdline.RepositoryMapping;
 import com.google.devtools.build.lib.concurrent.ThreadSafety.ThreadSafe;
 import javax.annotation.Nullable;
 
@@ -33,6 +34,19 @@ public interface ActionExecutionMetadata extends ActionAnalysisMetadata {
   @Nullable
   String getProgressMessage();
 
+  /**
+   * A variant of {@link #getProgressMessage} that additionally takes the {@link RepositoryMapping}
+   * of the main repository, which can be used by the implementation to emit labels with apparent
+   * instead of canonical repository names. A return value of {@code null} indicates no message
+   * should be reported.
+   *
+   * <p>The default implementation simply returns the result of {@link #getProgressMessage}.
+   */
+  @Nullable
+  default String getProgressMessage(RepositoryMapping mainRepositoryMapping) {
+    return getProgressMessage();
+  }
+
   /**
    * Returns a human-readable description of the inputs to {@link #getKey(ActionKeyContext)}. Used
    * in the output from '--explain', and in error messages for '--check_up_to_date' and
diff --git a/src/main/java/com/google/devtools/build/lib/pkgcache/LoadingPhaseCompleteEvent.java b/src/main/java/com/google/devtools/build/lib/pkgcache/LoadingPhaseCompleteEvent.java
index aad9f721f1ba05..f40f7a2ceb5aae 100644
--- a/src/main/java/com/google/devtools/build/lib/pkgcache/LoadingPhaseCompleteEvent.java
+++ b/src/main/java/com/google/devtools/build/lib/pkgcache/LoadingPhaseCompleteEvent.java
@@ -16,6 +16,7 @@
 import com.google.common.base.Preconditions;
 import com.google.common.collect.ImmutableSet;
 import com.google.devtools.build.lib.cmdline.Label;
+import com.google.devtools.build.lib.cmdline.RepositoryMapping;
 import com.google.devtools.build.lib.events.ExtendedEventHandler;
 
 /**
@@ -24,6 +25,7 @@
 public final class LoadingPhaseCompleteEvent implements ExtendedEventHandler.Postable {
   private final ImmutableSet<Label> labels;
   private final ImmutableSet<Label> filteredLabels;
+  private final RepositoryMapping mainRepositoryMapping;
 
   /**
    * Construct the event.
@@ -33,9 +35,11 @@ public final class LoadingPhaseCompleteEvent implements ExtendedEventHandler.Pos
    */
   public LoadingPhaseCompleteEvent(
       ImmutableSet<Label> labels,
-      ImmutableSet<Label> filteredLabels) {
+      ImmutableSet<Label> filteredLabels,
+      RepositoryMapping mainRepositoryMapping) {
     this.labels = Preconditions.checkNotNull(labels);
     this.filteredLabels = Preconditions.checkNotNull(filteredLabels);
+    this.mainRepositoryMapping = Preconditions.checkNotNull(mainRepositoryMapping);
   }
 
   /**
@@ -53,6 +57,13 @@ public ImmutableSet<Label> getFilteredLabels() {
     return filteredLabels;
   }
 
+  /**
+   * @return The repository mapping of the main repository.
+   */
+  public RepositoryMapping getMainRepositoryMapping() {
+    return mainRepositoryMapping;
+  }
+
   @Override
   public boolean storeForReplay() {
     return true;
diff --git a/src/main/java/com/google/devtools/build/lib/runtime/SkymeldUiStateTracker.java b/src/main/java/com/google/devtools/build/lib/runtime/SkymeldUiStateTracker.java
index a61db61a2cb033..6ce72a6cd894cc 100644
--- a/src/main/java/com/google/devtools/build/lib/runtime/SkymeldUiStateTracker.java
+++ b/src/main/java/com/google/devtools/build/lib/runtime/SkymeldUiStateTracker.java
@@ -171,6 +171,7 @@ void loadingComplete(LoadingPhaseCompleteEvent event) {
     } else {
       additionalMessage = labelsCount + " targets";
     }
+    mainRepositoryMapping = event.getMainRepositoryMapping();
   }
 
   @Override
diff --git a/src/main/java/com/google/devtools/build/lib/runtime/UiStateTracker.java b/src/main/java/com/google/devtools/build/lib/runtime/UiStateTracker.java
index f270dd87e11680..14183b40c01d6b 100644
--- a/src/main/java/com/google/devtools/build/lib/runtime/UiStateTracker.java
+++ b/src/main/java/com/google/devtools/build/lib/runtime/UiStateTracker.java
@@ -42,6 +42,8 @@
 import com.google.devtools.build.lib.buildtool.buildevent.TestFilteringCompleteEvent;
 import com.google.devtools.build.lib.clock.Clock;
 import com.google.devtools.build.lib.cmdline.Label;
+import com.google.devtools.build.lib.cmdline.RepositoryMapping;
+import com.google.devtools.build.lib.events.Event;
 import com.google.devtools.build.lib.events.ExtendedEventHandler.FetchProgress;
 import com.google.devtools.build.lib.pkgcache.LoadingPhaseCompleteEvent;
 import com.google.devtools.build.lib.skyframe.ConfigurationPhaseStartedEvent;
@@ -69,7 +71,7 @@
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.atomic.AtomicInteger;
 import javax.annotation.Nullable;
-import javax.annotation.concurrent.GuardedBy;
+import javax.annotation.concurrent.GuardedBy; 
 import javax.annotation.concurrent.ThreadSafe;
 
 /** Tracks state for the UI. */
@@ -89,6 +91,8 @@ class UiStateTracker {
 
   private String status;
   protected String additionalMessage;
+  // Not null after the loading phase has completed.
+  protected RepositoryMapping mainRepositoryMapping;
 
   protected final Clock clock;
 
@@ -427,6 +431,7 @@ void loadingComplete(LoadingPhaseCompleteEvent event) {
     } else {
       additionalMessage = count + " targets";
     }
+    mainRepositoryMapping = event.getMainRepositoryMapping();
   }
 
   /**
@@ -641,11 +646,11 @@ static String suffix(String s, int len) {
    * If possible come up with a human-readable description of the label that fits within the given
    * width; a non-positive width indicates not no restriction at all.
    */
-  private static String shortenedLabelString(Label label, int width) {
+  private String shortenedLabelString(Label label, int width) {
     if (width <= 0) {
-      return label.toString();
+      return label.getDisplayForm(mainRepositoryMapping);
     }
-    String name = label.toString();
+    String name = label.getDisplayForm(mainRepositoryMapping);
     if (name.length() <= width) {
       return name;
     }
@@ -787,7 +792,7 @@ protected String describeAction(
       postfix += " " + strategy;
     }
 
-    String message = action.getProgressMessage();
+    String message = action.getProgressMessage(mainRepositoryMapping);
     if (message == null) {
       message = action.prettyPrint();
     }
diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/TargetPatternPhaseFunction.java b/src/main/java/com/google/devtools/build/lib/skyframe/TargetPatternPhaseFunction.java
index 4b2153e62a5407..18d1e8e7ac158a 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/TargetPatternPhaseFunction.java
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/TargetPatternPhaseFunction.java
@@ -238,7 +238,11 @@ public TargetPatternPhaseValue compute(SkyKey key, Environment env) throws Inter
                 mapOriginalPatternsToLabels(expandedPatterns, targets.getTargets()),
                 testSuiteExpansions.buildOrThrow()));
     env.getListener()
-        .post(new LoadingPhaseCompleteEvent(result.getTargetLabels(), removedTargetLabels));
+        .post(
+            new LoadingPhaseCompleteEvent(
+                result.getTargetLabels(),
+                removedTargetLabels,
+                repositoryMappingValue.getRepositoryMapping()));
     return result;
   }
 

diff --git a/src/test/java/com/google/devtools/build/lib/runtime/SkymeldUiStateTrackerTest.java b/src/test/java/com/google/devtools/build/lib/runtime/SkymeldUiStateTrackerTest.java
index f91c05854143a3..c26dffb4e6c5f7 100644
--- a/src/test/java/com/google/devtools/build/lib/runtime/SkymeldUiStateTrackerTest.java
+++ b/src/test/java/com/google/devtools/build/lib/runtime/SkymeldUiStateTrackerTest.java
@@ -24,6 +24,7 @@
 import com.google.devtools.build.lib.buildtool.ExecutionProgressReceiver;
 import com.google.devtools.build.lib.buildtool.buildevent.BuildCompleteEvent;
 import com.google.devtools.build.lib.buildtool.buildevent.ExecutionProgressReceiverAvailableEvent;
+import com.google.devtools.build.lib.cmdline.RepositoryMapping;
 import com.google.devtools.build.lib.pkgcache.LoadingPhaseCompleteEvent;
 import com.google.devtools.build.lib.runtime.SkymeldUiStateTracker.BuildStatus;
 import com.google.devtools.build.lib.skyframe.ConfigurationPhaseStartedEvent;
@@ -74,7 +75,8 @@ public void loadingComplete_stateChanges() {
     uiStateTracker.buildStatus = BuildStatus.TARGET_PATTERN_PARSING;
 
     uiStateTracker.loadingComplete(
-        new LoadingPhaseCompleteEvent(ImmutableSet.of(), ImmutableSet.of()));
+        new LoadingPhaseCompleteEvent(
+            ImmutableSet.of(), ImmutableSet.of(), RepositoryMapping.ALWAYS_FALLBACK));
 
     assertThat(uiStateTracker.buildStatus).isEqualTo(BuildStatus.LOADING_COMPLETE);
   }
diff --git a/src/test/java/com/google/devtools/build/lib/runtime/UiStateTrackerTest.java b/src/test/java/com/google/devtools/build/lib/runtime/UiStateTrackerTest.java
index 497b391c26a836..fdd89a87513adf 100644
--- a/src/test/java/com/google/devtools/build/lib/runtime/UiStateTrackerTest.java
+++ b/src/test/java/com/google/devtools/build/lib/runtime/UiStateTrackerTest.java
@@ -18,7 +18,10 @@
 import static org.hamcrest.CoreMatchers.containsString;
 import static org.hamcrest.CoreMatchers.not;
 import static org.hamcrest.MatcherAssert.assertThat;
+import static org.mockito.ArgumentMatchers.eq;
 import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.never;
+import static org.mockito.Mockito.verify;
 import static org.mockito.Mockito.when;
 
 import com.google.common.collect.ImmutableList;
@@ -54,6 +57,8 @@
 import com.google.devtools.build.lib.buildtool.buildevent.TestFilteringCompleteEvent;
 import com.google.devtools.build.lib.cmdline.Label;
 import com.google.devtools.build.lib.cmdline.LabelSyntaxException;
+import com.google.devtools.build.lib.cmdline.RepositoryMapping;
+import com.google.devtools.build.lib.cmdline.RepositoryName;
 import com.google.devtools.build.lib.events.ExtendedEventHandler.FetchProgress;
 import com.google.devtools.build.lib.pkgcache.LoadingPhaseCompleteEvent;
 import com.google.devtools.build.lib.runtime.SkymeldUiStateTracker.BuildStatus;
@@ -83,12 +88,15 @@
 import net.starlark.java.syntax.Location;
 import org.junit.Test;
 import org.junit.runner.RunWith;
+import org.mockito.AdditionalMatchers;
 
 /** Tests {@link UiStateTracker}. */
 @RunWith(TestParameterInjector.class)
 public class UiStateTrackerTest extends FoundationTestCase {
 
   @TestParameter boolean isSkymeld;
+  static final RepositoryMapping MOCK_REPO_MAPPING =
+      RepositoryMapping.createAllowingFallback(ImmutableMap.of("main", RepositoryName.MAIN));
 
   private UiStateTracker getUiStateTracker(ManualClock clock) {
     if (isSkymeld) {
@@ -186,8 +194,11 @@ private Action mockAction(String progressMessage, String primaryOutput) {
         ActionsTestUtil.createArtifact(ArtifactRoot.asSourceRoot(Root.fromPath(outputBase)), path);
 
     Action action = mock(Action.class);
-    when(action.getProgressMessage()).thenReturn(progressMessage);
+    when(action.getProgressMessage(eq(MOCK_REPO_MAPPING))).thenReturn(progressMessage);
     when(action.getPrimaryOutput()).thenReturn(artifact);
+
+    verify(action, never()).getProgressMessage(AdditionalMatchers.not(eq(MOCK_REPO_MAPPING)));
+    verify(action, never()).getProgressMessage();
     return action;
   }
 
@@ -208,9 +219,13 @@ private ActionOwner dummyActionOwner() throws LabelSyntaxException {
   }
 
   private void simulateExecutionPhase(UiStateTracker uiStateTracker) {
+    uiStateTracker.loadingComplete(
+        new LoadingPhaseCompleteEvent(ImmutableSet.of(), ImmutableSet.of(), MOCK_REPO_MAPPING));
     if (this.isSkymeld) {
       // SkymeldUiStateTracker needs to be in the configuration phase before the execution phase.
       ((SkymeldUiStateTracker) uiStateTracker).buildStatus = BuildStatus.ANALYSIS_COMPLETE;
+    } else {
+      String unused = uiStateTracker.analysisComplete();
     }
     uiStateTracker.progressReceiverAvailable(
         new ExecutionProgressReceiverAvailableEvent(dummyExecutionProgressReceiver()));
@@ -254,7 +269,7 @@ public void testLoadingActivity() throws IOException {
 
     // When it is configuring targets.
     stateTracker.loadingComplete(
-        new LoadingPhaseCompleteEvent(ImmutableSet.of(), ImmutableSet.of()));
+        new LoadingPhaseCompleteEvent(ImmutableSet.of(), ImmutableSet.of(), MOCK_REPO_MAPPING));
     String additionalMessage = "5 targets";
     stateTracker.additionalMessage = additionalMessage;
     String configuredTargetProgressString = "5 targets configured";
