diff --git a/action-binding-generator/src/main/kotlin/io/github/typesafegithub/workflows/actionbindinggenerator/domain/ActionCoords.kt b/action-binding-generator/src/main/kotlin/io/github/typesafegithub/workflows/actionbindinggenerator/domain/ActionCoords.kt
index 85d6cc0c39..6650508de2 100644
--- a/action-binding-generator/src/main/kotlin/io/github/typesafegithub/workflows/actionbindinggenerator/domain/ActionCoords.kt
+++ b/action-binding-generator/src/main/kotlin/io/github/typesafegithub/workflows/actionbindinggenerator/domain/ActionCoords.kt
@@ -27,7 +27,7 @@ public val ActionCoords.repoName: String get() =
  * action lives.
  */
 public val ActionCoords.subName: String get() =
-    if (isTopLevel) "" else name.substringAfter("/")
+    if (isTopLevel) "" else "/${name.substringAfter("/")}"
 
 internal fun String.toActionCoords(): ActionCoords {
     val (ownerAndName, version) = this.split('@')
diff --git a/action-binding-generator/src/main/kotlin/io/github/typesafegithub/workflows/actionbindinggenerator/typing/TypesProviding.kt b/action-binding-generator/src/main/kotlin/io/github/typesafegithub/workflows/actionbindinggenerator/typing/TypesProviding.kt
index cf780d44c1..56aeb5b3e2 100644
--- a/action-binding-generator/src/main/kotlin/io/github/typesafegithub/workflows/actionbindinggenerator/typing/TypesProviding.kt
+++ b/action-binding-generator/src/main/kotlin/io/github/typesafegithub/workflows/actionbindinggenerator/typing/TypesProviding.kt
@@ -29,18 +29,18 @@ internal fun ActionCoords.provideTypes(
         ?: Pair(emptyMap(), null)
 
 private fun ActionCoords.actionTypesYmlUrl(gitRef: String) =
-    "https://raw.githubusercontent.com/$owner/$repoName/$gitRef/$subName/action-types.yml"
+    "https://raw.githubusercontent.com/$owner/$repoName/$gitRef$subName/action-types.yml"
 
 private fun ActionCoords.actionTypesFromCatalog() =
     "https://raw.githubusercontent.com/typesafegithub/github-actions-typing-catalog/" +
-        "main/typings/$owner/$repoName/$version/$subName/action-types.yml"
+        "main/typings/$owner/$repoName/$version$subName/action-types.yml"
 
 private fun ActionCoords.catalogMetadata() =
     "https://raw.githubusercontent.com/typesafegithub/github-actions-typing-catalog/" +
         "main/typings/$owner/$repoName/metadata.yml"
 
 private fun ActionCoords.actionTypesYamlUrl(gitRef: String) =
-    "https://raw.githubusercontent.com/$owner/$repoName/$gitRef/$subName/action-types.yaml"
+    "https://raw.githubusercontent.com/$owner/$repoName/$gitRef$subName/action-types.yaml"
 
 private fun ActionCoords.fetchTypingMetadata(
     metadataRevision: MetadataRevision,
diff --git a/action-binding-generator/src/test/kotlin/io/github/typesafegithub/workflows/actionbindinggenerator/typing/TypesProvidingTest.kt b/action-binding-generator/src/test/kotlin/io/github/typesafegithub/workflows/actionbindinggenerator/typing/TypesProvidingTest.kt
index dee642037b..2464a5c094 100644
--- a/action-binding-generator/src/test/kotlin/io/github/typesafegithub/workflows/actionbindinggenerator/typing/TypesProvidingTest.kt
+++ b/action-binding-generator/src/test/kotlin/io/github/typesafegithub/workflows/actionbindinggenerator/typing/TypesProvidingTest.kt
@@ -103,7 +103,7 @@ class TypesProvidingTest :
                 // Given
                 val fetchUri: (URI) -> String = {
                     when (it) {
-                        URI("https://raw.githubusercontent.com/some-owner/some-name/some-hash//action-types.yml") -> hostedByActionYml
+                        URI("https://raw.githubusercontent.com/some-owner/some-name/some-hash/action-types.yml") -> hostedByActionYml
                         else -> throw IOException()
                     }
                 }
@@ -116,11 +116,31 @@ class TypesProvidingTest :
                 types shouldBe Pair(mapOf("hosted-by-action-yml" to StringTyping), TypingActualSource.ACTION)
             }
 
+            test("only hosted by the subaction (.yml)") {
+                // Given
+                val fetchUri: (URI) -> String = {
+                    when (it) {
+                        URI(
+                            "https://raw.githubusercontent.com/some-owner/some-name/some-hash/some-sub/action-types.yml",
+                        ),
+                        -> hostedByActionYml
+                        else -> throw IOException()
+                    }
+                }
+                val actionCoord = ActionCoords("some-owner", "some-name/some-sub", "v3")
+
+                // When
+                val types = actionCoord.provideTypes(metadataRevision = CommitHash("some-hash"), fetchUri = fetchUri)
+
+                // Then
+                types shouldBe Pair(mapOf("hosted-by-action-yml" to StringTyping), TypingActualSource.ACTION)
+            }
+
             test("only hosted by the action (.yaml)") {
                 // Given
                 val fetchUri: (URI) -> String = {
                     when (it) {
-                        URI("https://raw.githubusercontent.com/some-owner/some-name/some-hash//action-types.yaml") -> hostedByActionYaml
+                        URI("https://raw.githubusercontent.com/some-owner/some-name/some-hash/action-types.yaml") -> hostedByActionYaml
                         else -> throw IOException()
                     }
                 }
@@ -133,12 +153,32 @@ class TypesProvidingTest :
                 types shouldBe Pair(mapOf("hosted-by-action-yaml" to StringTyping), TypingActualSource.ACTION)
             }
 
+            test("only hosted by the subaction (.yaml)") {
+                // Given
+                val fetchUri: (URI) -> String = {
+                    when (it) {
+                        URI(
+                            "https://raw.githubusercontent.com/some-owner/some-name/some-hash/some-sub/action-types.yaml",
+                        ),
+                        -> hostedByActionYaml
+                        else -> throw IOException()
+                    }
+                }
+                val actionCoord = ActionCoords("some-owner", "some-name/some-sub", "v3")
+
+                // When
+                val types = actionCoord.provideTypes(metadataRevision = CommitHash("some-hash"), fetchUri = fetchUri)
+
+                // Then
+                types shouldBe Pair(mapOf("hosted-by-action-yaml" to StringTyping), TypingActualSource.ACTION)
+            }
+
             test("only hosted by the action, both extensions") {
                 // Given
                 val fetchUri: (URI) -> String = {
                     when (it) {
-                        URI("https://raw.githubusercontent.com/some-owner/some-name/some-hash//action-types.yml") -> hostedByActionYml
-                        URI("https://raw.githubusercontent.com/some-owner/some-name/some-hash//action-types.yaml") -> hostedByActionYaml
+                        URI("https://raw.githubusercontent.com/some-owner/some-name/some-hash/action-types.yml") -> hostedByActionYml
+                        URI("https://raw.githubusercontent.com/some-owner/some-name/some-hash/action-types.yaml") -> hostedByActionYaml
                         else -> throw IOException()
                     }
                 }
@@ -151,13 +191,37 @@ class TypesProvidingTest :
                 types shouldBe Pair(mapOf("hosted-by-action-yml" to StringTyping), TypingActualSource.ACTION)
             }
 
+            test("only hosted by the subaction, both extensions") {
+                // Given
+                val fetchUri: (URI) -> String = {
+                    when (it) {
+                        URI(
+                            "https://raw.githubusercontent.com/some-owner/some-name/some-hash/some-sub/action-types.yml",
+                        ),
+                        -> hostedByActionYml
+                        URI(
+                            "https://raw.githubusercontent.com/some-owner/some-name/some-hash/some-sub/action-types.yaml",
+                        ),
+                        -> hostedByActionYaml
+                        else -> throw IOException()
+                    }
+                }
+                val actionCoord = ActionCoords("some-owner", "some-name/some-sub", "v3")
+
+                // When
+                val types = actionCoord.provideTypes(metadataRevision = CommitHash("some-hash"), fetchUri = fetchUri)
+
+                // Then
+                types shouldBe Pair(mapOf("hosted-by-action-yml" to StringTyping), TypingActualSource.ACTION)
+            }
+
             test("only stored in typing catalog") {
                 // Given
                 val fetchUri: (URI) -> String = {
                     when (it) {
                         URI(
                             "https://raw.githubusercontent.com/typesafegithub/github-actions-typing-catalog/" +
-                                "main/typings/some-owner/some-name/v3//action-types.yml",
+                                "main/typings/some-owner/some-name/v3/action-types.yml",
                         ),
                         -> storedInTypingCatalog
                         else -> throw IOException()
@@ -172,18 +236,39 @@ class TypesProvidingTest :
                 types shouldBe Pair(mapOf("stored-in-typing-catalog" to StringTyping), TypingActualSource.TYPING_CATALOG)
             }
 
+            test("only stored in typing catalog for subaction") {
+                // Given
+                val fetchUri: (URI) -> String = {
+                    when (it) {
+                        URI(
+                            "https://raw.githubusercontent.com/typesafegithub/github-actions-typing-catalog/" +
+                                "main/typings/some-owner/some-name/v3/some-sub/action-types.yml",
+                        ),
+                        -> storedInTypingCatalog
+                        else -> throw IOException()
+                    }
+                }
+                val actionCoord = ActionCoords("some-owner", "some-name/some-sub", "v3")
+
+                // When
+                val types = actionCoord.provideTypes(metadataRevision = CommitHash("some-hash"), fetchUri = fetchUri)
+
+                // Then
+                types shouldBe Pair(mapOf("stored-in-typing-catalog" to StringTyping), TypingActualSource.TYPING_CATALOG)
+            }
+
             test("hosted by action and stored in typing catalog") {
                 // Given
                 val fetchUri: (URI) -> String = {
                     when (it) {
                         URI(
                             "https://raw.githubusercontent.com/some-owner/some-name/" +
-                                "some-hash//action-types.yml",
+                                "some-hash/action-types.yml",
                         ),
                         -> hostedByActionYml
                         URI(
                             "https://raw.githubusercontent.com/typesafegithub/github-actions-typing-catalog/" +
-                                "main/typings/some-owner/some-name/v3//action-types.yml",
+                                "main/typings/some-owner/some-name/v3/action-types.yml",
                         ),
                         -> storedInTypingCatalog
                         else -> throw IOException()
@@ -198,6 +283,32 @@ class TypesProvidingTest :
                 types shouldBe Pair(mapOf("hosted-by-action-yml" to StringTyping), TypingActualSource.ACTION)
             }
 
+            test("hosted by subaction and stored in typing catalog") {
+                // Given
+                val fetchUri: (URI) -> String = {
+                    when (it) {
+                        URI(
+                            "https://raw.githubusercontent.com/some-owner/some-name/" +
+                                "some-hash/some-sub/action-types.yml",
+                        ),
+                        -> hostedByActionYml
+                        URI(
+                            "https://raw.githubusercontent.com/typesafegithub/github-actions-typing-catalog/" +
+                                "main/typings/some-owner/some-name/v3/some-sub/action-types.yml",
+                        ),
+                        -> storedInTypingCatalog
+                        else -> throw IOException()
+                    }
+                }
+                val actionCoord = ActionCoords("some-owner", "some-name/some-sub", "v3")
+
+                // When
+                val types = actionCoord.provideTypes(metadataRevision = CommitHash("some-hash"), fetchUri = fetchUri)
+
+                // Then
+                types shouldBe Pair(mapOf("hosted-by-action-yml" to StringTyping), TypingActualSource.ACTION)
+            }
+
             test("only stored in typing catalog for older version") {
                 // Given
                 val fetchUri: (URI) -> String = {
@@ -209,7 +320,7 @@ class TypesProvidingTest :
                         -> metadata
                         URI(
                             "https://raw.githubusercontent.com/typesafegithub/github-actions-typing-catalog/" +
-                                "main/typings/some-owner/some-name/v4//action-types.yml",
+                                "main/typings/some-owner/some-name/v4/action-types.yml",
                         ),
                         -> storedInTypingCatalogForOlderVersion
                         else -> throw IOException()
@@ -224,6 +335,32 @@ class TypesProvidingTest :
                 types shouldBe Pair(mapOf("stored-in-typing-catalog-for-older-version" to StringTyping), TypingActualSource.TYPING_CATALOG)
             }
 
+            test("only stored in typing catalog for older version of subaction") {
+                // Given
+                val fetchUri: (URI) -> String = {
+                    when (it) {
+                        URI(
+                            "https://raw.githubusercontent.com/typesafegithub/github-actions-typing-catalog/" +
+                                "main/typings/some-owner/some-name/metadata.yml",
+                        ),
+                        -> metadata
+                        URI(
+                            "https://raw.githubusercontent.com/typesafegithub/github-actions-typing-catalog/" +
+                                "main/typings/some-owner/some-name/v4/some-sub/action-types.yml",
+                        ),
+                        -> storedInTypingCatalogForOlderVersion
+                        else -> throw IOException()
+                    }
+                }
+                val actionCoord = ActionCoords("some-owner", "some-name/some-sub", "v6")
+
+                // When
+                val types = actionCoord.provideTypes(metadataRevision = CommitHash("some-hash"), fetchUri = fetchUri)
+
+                // Then
+                types shouldBe Pair(mapOf("stored-in-typing-catalog-for-older-version" to StringTyping), TypingActualSource.TYPING_CATALOG)
+            }
+
             test("metadata available but no version available") {
                 // Given
                 val fetchUri: (URI) -> String = {