diff --git a/.changeset/patch-aw-yml-schedule-seed.md b/.changeset/patch-aw-yml-schedule-seed.md
new file mode 100644
index 00000000000..d43c46f5059
--- /dev/null
+++ b/.changeset/patch-aw-yml-schedule-seed.md
@@ -0,0 +1,5 @@
+---
+"gh-aw": patch
+---
+
+Allow `aw.yml` to provide the default seed for fuzzy schedule scattering.
diff --git a/docs/src/content/docs/reference/aw-yml-package-manifest.md b/docs/src/content/docs/reference/aw-yml-package-manifest.md
index f401b4349d0..658278c418d 100644
--- a/docs/src/content/docs/reference/aw-yml-package-manifest.md
+++ b/docs/src/content/docs/reference/aw-yml-package-manifest.md
@@ -33,6 +33,7 @@ The package root is the folder that contains `aw.yml`.
 | `description` | string | No | Optional package description. `gh aw add` warns when it exceeds 255 characters. |
 | `private` | boolean | No | Marks the package as unavailable for installation. Defaults to `false`; `gh aw add` refuses packages set to `true`. |
 | `experimental` | boolean | No | Marks the package as experimental. Defaults to `false`; `gh aw add` displays a warning when set to `true`. |
+| `schedule-seed` | string | No | Repository slug in `owner/repo` form used for fuzzy schedule scattering by `gh aw compile`. The `--schedule-seed` flag takes precedence. |
 | `files` | array of strings | No | Deprecated; use `includes`. Package-root-relative paths. Agentic markdown workflows under `workflows/` or `.github/workflows/`; raw GitHub Actions YAML (`.yml`) is also accepted as direct children of `.github/workflows/`. |
 | `includes` | array | No | Installable entries, or paths to other `aw.yml` manifests whose installable files are included recursively. Each entry is either a path string (same rules as `files`, plus skill and agent paths), a path ending in `/*` that matches supported direct children, or a source-to-destination mapping. |
 | `resources` | array | No | Repository assets copied from package-relative `source` paths to allowlisted repository-relative `destination` paths. |
diff --git a/docs/src/content/docs/specs/repository-package-manifest-specification.md b/docs/src/content/docs/specs/repository-package-manifest-specification.md
index 0c4e0a23757..a599dffc2c9 100644
--- a/docs/src/content/docs/specs/repository-package-manifest-specification.md
+++ b/docs/src/content/docs/specs/repository-package-manifest-specification.md
@@ -50,6 +50,7 @@ The manifest document MUST be a YAML mapping. Unknown top-level fields MUST be r
 | `license` | string | No | SPDX license identifier or license name for the package. |
 | `private` | boolean | No | Whether the package is unavailable for installation. Defaults to `false`. |
 | `experimental` | boolean | No | Whether the package is experimental. Defaults to `false`. |
+| `schedule-seed` | string | No | Repository slug used for fuzzy schedule scattering when the compile flag is omitted. |
 | `imports` | array of strings | No | Paths to package manifests included recursively in the install set. |
 | `files` | array of strings | No | Deprecated. Explicit installable workflow file list. Use `includes` instead. |
 | `includes` | array of strings or mappings | No | Explicit installable package entries. String entries use path conventions; mapping entries declare an explicit source-to-destination install path. |
@@ -104,6 +105,12 @@ If omitted, `private` defaults to `false`. When `private` is `true`, `gh aw add`
 
 If omitted, `experimental` defaults to `false`. When `experimental` is `true`, `gh aw add` MUST warn before installing the package.
 
+### 4.9.1 `schedule-seed`
+
+If present, `schedule-seed` MUST be a string in `owner/repo` form. `gh aw compile`
+MUST use it for fuzzy schedule scattering when `--schedule-seed` is omitted. An
+explicit `--schedule-seed` value MUST take precedence.
+
 ### 4.10 `files`
 
 If present, `files` MUST be an array of strings.
diff --git a/pkg/cli/add_package_manifest_parse.go b/pkg/cli/add_package_manifest_parse.go
index 0c665ba076d..f0a8128c4aa 100644
--- a/pkg/cli/add_package_manifest_parse.go
+++ b/pkg/cli/add_package_manifest_parse.go
@@ -29,6 +29,7 @@ type repositoryPackageManifest struct {
 	License         string
 	Private         bool
 	Experimental    bool
+	ScheduleSeed    string
 	Imports         []string
 	Includes        []repositoryPackageInclude
 	Files           []string
@@ -173,6 +174,9 @@ func populateRepositoryPackageManifestBasicMetadata(manifest *repositoryPackageM
 	if experimental, ok := root["experimental"].(bool); ok {
 		manifest.Experimental = experimental
 	}
+	if scheduleSeed, ok := stringValue(root["schedule-seed"]); ok {
+		manifest.ScheduleSeed = scheduleSeed
+	}
 }
 
 func populateRepositoryPackageManifestExtensions(manifest *repositoryPackageManifest, root map[string]any, manifestPath string, warnings []string) ([]string, error) {
diff --git a/pkg/cli/compile_orchestrator.go b/pkg/cli/compile_orchestrator.go
index 583233e72a7..46c4fb0a744 100644
--- a/pkg/cli/compile_orchestrator.go
+++ b/pkg/cli/compile_orchestrator.go
@@ -115,10 +115,8 @@ func CompileWorkflows(ctx context.Context, config CompileConfig) ([]*workflow.Wo
 		return nil, err
 	}
 
-	compiler := createAndConfigureCompiler(config)
-	compiler.SetContext(ctx)
-
-	if err := validateRepositoryManifestForCompilation(config, stats, &validationResults); err != nil {
+	manifest, err := validateRepositoryManifestForCompilation(config, stats, &validationResults)
+	if err != nil {
 		if config.JSONOutput {
 			if outputErr := outputResults(stats, &validationResults, config); outputErr != nil {
 				return nil, outputErr
@@ -126,6 +124,10 @@ func CompileWorkflows(ctx context.Context, config CompileConfig) ([]*workflow.Wo
 		}
 		return nil, err
 	}
+	config = applyRepositoryManifestDefaults(config, manifest)
+
+	compiler := createAndConfigureCompiler(config)
+	compiler.SetContext(ctx)
 
 	// Handle watch mode (early return)
 	if config.Watch {
diff --git a/pkg/cli/compile_repository_manifest.go b/pkg/cli/compile_repository_manifest.go
index 2a090f362b7..8040ff62f45 100644
--- a/pkg/cli/compile_repository_manifest.go
+++ b/pkg/cli/compile_repository_manifest.go
@@ -16,34 +16,41 @@ var compileRepositoryManifestLog = logger.New("cli:compile_repository_manifest")
 
 var findGitRootForManifestValidation = gitutil.FindGitRoot
 
-func validateRepositoryManifestForCompilation(config CompileConfig, stats *CompilationStats, validationResults *[]ValidationResult) error {
+func applyRepositoryManifestDefaults(config CompileConfig, manifest *repositoryPackageManifest) CompileConfig {
+	if config.ScheduleSeed == "" && manifest != nil {
+		config.ScheduleSeed = manifest.ScheduleSeed
+	}
+	return config
+}
+
+func validateRepositoryManifestForCompilation(config CompileConfig, stats *CompilationStats, validationResults *[]ValidationResult) (*repositoryPackageManifest, error) {
 	compileRepositoryManifestLog.Print("Validating repository manifest for compilation")
 
 	gitRoot, err := findGitRootForManifestValidation()
 	if err != nil {
 		if errors.Is(err, gitutil.ErrNotGitRepository) {
 			compileRepositoryManifestLog.Print("Not in a git repository, skipping manifest validation")
-			return nil
+			return nil, nil
 		}
-		return fmt.Errorf("failed to find git root for manifest validation: %w", err)
+		return nil, fmt.Errorf("failed to find git root for manifest validation: %w", err)
 	}
 
 	manifestPath, err := findLocalRepositoryPackageManifest(gitRoot)
 	if err != nil {
-		return err
+		return nil, err
 	}
 	if manifestPath == "" {
 		compileRepositoryManifestLog.Printf("No repository manifest found in %s", gitRoot)
-		return nil
+		return nil, nil
 	}
 
 	compileRepositoryManifestLog.Printf("Found repository manifest at %s", manifestPath)
 	content, err := os.ReadFile(manifestPath)
 	if err != nil {
-		return fmt.Errorf("failed to read Agentic Workflow manifest %q: %w", manifestPath, err)
+		return nil, fmt.Errorf("failed to read Agentic Workflow manifest %q: %w", manifestPath, err)
 	}
 
-	_, warnings, parseErr := parseRepositoryPackageManifest(manifestPath, content)
+	manifest, warnings, parseErr := parseRepositoryPackageManifest(manifestPath, content)
 	if parseErr == nil {
 		parseErr = validateLocalRepositoryPackageContents(manifestPath)
 	}
@@ -62,7 +69,10 @@ func validateRepositoryManifestForCompilation(config CompileConfig, stats *Compi
 			Message: warning,
 		})
 	}
-	return reportRepositoryManifestValidation(config, validationResults, warnings, parseErr, result)
+	if err := reportRepositoryManifestValidation(config, validationResults, warnings, parseErr, result); err != nil {
+		return nil, err
+	}
+	return manifest, nil
 }
 
 func reportRepositoryManifestValidation(config CompileConfig, validationResults *[]ValidationResult, warnings []string, parseErr error, result ValidationResult) error {
diff --git a/pkg/cli/compile_repository_manifest_test.go b/pkg/cli/compile_repository_manifest_test.go
index 051b54256ac..28c3f9661aa 100644
--- a/pkg/cli/compile_repository_manifest_test.go
+++ b/pkg/cli/compile_repository_manifest_test.go
@@ -12,7 +12,9 @@ import (
 	"path/filepath"
 	"testing"
 
+	"github.com/github/gh-aw/pkg/parser"
 	"github.com/github/gh-aw/pkg/testutil"
+	"github.com/github/gh-aw/pkg/workflow"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 )
@@ -179,6 +181,46 @@ engine: copilot
 	require.NoError(t, err)
 }
 
+func TestCompileWorkflows_UsesManifestScheduleSeed(t *testing.T) {
+	tmpDir := testutil.TempDir(t, "aw-manifest-schedule-seed-*")
+	originalWd, err := os.Getwd()
+	require.NoError(t, err)
+	t.Cleanup(func() { _ = os.Chdir(originalWd) })
+	require.NoError(t, os.Chdir(tmpDir))
+
+	cmd := exec.Command("git", "init")
+	cmd.Dir = tmpDir
+	require.NoError(t, cmd.Run())
+
+	require.NoError(t, os.MkdirAll(filepath.Join(tmpDir, ".github", "workflows"), 0o755))
+	require.NoError(t, os.WriteFile(filepath.Join(tmpDir, ".github", "workflows", "test.md"), []byte(`---
+on: daily
+permissions:
+  contents: read
+engine: copilot
+---
+
+# Test
+`), 0o644))
+	require.NoError(t, os.WriteFile(filepath.Join(tmpDir, "README.md"), []byte("# Repo Assist\n"), 0o644))
+	require.NoError(t, os.WriteFile(filepath.Join(tmpDir, "aw.yml"), []byte(`name: Repo Assist
+schedule-seed: github/gh-aw
+`), 0o644))
+
+	wasRelease := workflow.IsRelease()
+	workflow.SetIsRelease(true)
+	t.Cleanup(func() { workflow.SetIsRelease(wasRelease) })
+
+	_, err = CompileWorkflows(context.Background(), CompileConfig{})
+	require.NoError(t, err)
+
+	lockContent, err := os.ReadFile(filepath.Join(tmpDir, ".github", "workflows", "test.lock.yml"))
+	require.NoError(t, err)
+	expectedCron, err := parser.ScatterSchedule("FUZZY:DAILY * * *", "github/gh-aw/.github/workflows/test.md")
+	require.NoError(t, err)
+	assert.Contains(t, string(lockContent), expectedCron, "compiled schedule should use the aw.yml schedule seed")
+}
+
 func TestCompileWorkflows_ResolvesImportedManifestRootRelativeWorkflow(t *testing.T) {
 	tmpDir := testutil.TempDir(t, "aw-manifest-import-root-relative-*")
 	originalWd, err := os.Getwd()
@@ -287,8 +329,45 @@ func TestValidateRepositoryManifestForCompilation_PropagatesGitRootErrors(t *tes
 
 	stats := &CompilationStats{}
 	var results []ValidationResult
-	err := validateRepositoryManifestForCompilation(CompileConfig{}, stats, &results)
+	_, err := validateRepositoryManifestForCompilation(CompileConfig{}, stats, &results)
 	require.Error(t, err)
 	require.ErrorContains(t, err, "failed to find git root for manifest validation")
 	require.ErrorContains(t, err, "permission denied")
 }
+
+func TestApplyRepositoryManifestDefaults_ScheduleSeed(t *testing.T) {
+	t.Parallel()
+
+	manifest := &repositoryPackageManifest{ScheduleSeed: "github/gh-aw"}
+
+	t.Run("uses manifest value when flag omitted", func(t *testing.T) {
+		config := applyRepositoryManifestDefaults(CompileConfig{}, manifest)
+		assert.Equal(t, "github/gh-aw", config.ScheduleSeed)
+	})
+
+	t.Run("preserves explicit flag value", func(t *testing.T) {
+		config := applyRepositoryManifestDefaults(CompileConfig{ScheduleSeed: "octo/repo"}, manifest)
+		assert.Equal(t, "octo/repo", config.ScheduleSeed)
+	})
+
+	t.Run("handles missing manifest", func(t *testing.T) {
+		config := applyRepositoryManifestDefaults(CompileConfig{}, nil)
+		assert.Empty(t, config.ScheduleSeed)
+	})
+}
+
+func TestParseRepositoryPackageManifest_ScheduleSeed(t *testing.T) {
+	t.Parallel()
+
+	manifest, _, err := parseRepositoryPackageManifest("aw.yml", []byte("name: Repo Assist\nschedule-seed: github/gh-aw\n"))
+	require.NoError(t, err)
+	assert.Equal(t, "github/gh-aw", manifest.ScheduleSeed)
+}
+
+func TestParseRepositoryPackageManifest_RejectsInvalidScheduleSeed(t *testing.T) {
+	t.Parallel()
+
+	_, _, err := parseRepositoryPackageManifest("aw.yml", []byte("name: Repo Assist\nschedule-seed: invalid\n"))
+	require.Error(t, err)
+	require.ErrorContains(t, err, "schedule-seed")
+}
diff --git a/pkg/parser/schemas/aw_manifest_schema.json b/pkg/parser/schemas/aw_manifest_schema.json
index 5f7f3eb62b6..46e67d02415 100644
--- a/pkg/parser/schemas/aw_manifest_schema.json
+++ b/pkg/parser/schemas/aw_manifest_schema.json
@@ -40,6 +40,11 @@
       "default": false,
       "description": "Whether the package is experimental and may change without notice."
     },
+    "schedule-seed": {
+      "type": "string",
+      "pattern": "^[^/\\s]+/[^/\\s]+$",
+      "description": "Repository slug used as the seed for fuzzy schedule scattering when --schedule-seed is not provided."
+    },
     "includes": {
       "type": "array",
       "description": "Installable package entries, or paths to aw.yml manifests to compose recursively. String entries use folder naming conventions to infer type: workflows under workflows/, agentic-workflows/, or .github/workflows/; skill directories under skills/ or .github/skills/; agent files under agents/ or .github/agents/. A string may end in /* to include supported direct children of one directory. Object entries map a package-relative 'source' to a repository-root-relative 'destination' under .github/workflows/. A wildcard mapping installs each matching file into the destination folder.",