diff --git a/src/platform/curseforge.rs b/src/platform/curseforge.rs
index f1f8008..2cc7b90 100644
--- a/src/platform/curseforge.rs
+++ b/src/platform/curseforge.rs
@@ -404,6 +404,8 @@ impl PlatformClient for CurseForgePlatform {
     }
   }
 
+  /// Uses CurseForge's `/fingerprints/432` endpoint to resolve projects by
+  /// their hashes in batch.
   async fn request_projects_from_hashes(
     &self,
     hashes: &[String],
diff --git a/src/platform/github.rs b/src/platform/github.rs
index 57582ea..802e3c7 100644
--- a/src/platform/github.rs
+++ b/src/platform/github.rs
@@ -414,6 +414,20 @@ impl PlatformClient for GitHubPlatform {
       Err(e) => Err(e),
     }
   }
+
+  /// GitHub does not support hash-based batch lookup. Returns an empty list.
+  async fn request_projects_from_hashes(
+    &self,
+    hashes: &[String],
+    algorithm: &str,
+  ) -> Result<Vec<Project>> {
+    log::debug!(
+      "GitHub does not support batch hash lookup ({} hashes, algorithm={})",
+      hashes.len(),
+      algorithm
+    );
+    Ok(Vec::new())
+  }
 }
 
 // GitHub API models
diff --git a/src/platform/modrinth.rs b/src/platform/modrinth.rs
index 906a264..94ebf84 100644
--- a/src/platform/modrinth.rs
+++ b/src/platform/modrinth.rs
@@ -277,6 +277,8 @@ impl PlatformClient for ModrinthPlatform {
     Ok(Some(self.convert_project(mr_project)))
   }
 
+  /// Uses Modrinth's `/v2/version_files` endpoint to resolve projects by
+  /// their hashes in batch.
   async fn request_projects_from_hashes(
     &self,
     hashes: &[String],
diff --git a/src/platform/multiplatform.rs b/src/platform/multiplatform.rs
index 5ff8a8b..521f4ec 100644
--- a/src/platform/multiplatform.rs
+++ b/src/platform/multiplatform.rs
@@ -203,6 +203,8 @@ impl PlatformClient for MultiplatformPlatform {
     }
   }
 
+  /// Delegates to both CurseForge and Modrinth in parallel, then deduplicates
+  /// results.
   async fn request_projects_from_hashes(
     &self,
     hashes: &[String],
diff --git a/src/platform/traits.rs b/src/platform/traits.rs
index db115c9..8319480 100644
--- a/src/platform/traits.rs
+++ b/src/platform/traits.rs
@@ -37,4 +37,17 @@ pub trait PlatformClient: Send + Sync {
     &self,
     slug: &str,
   ) -> Result<Option<Project>>;
+
+  /// Request multiple projects by their hashes (Modrinth) or bytes
+  /// (CurseForge).
+  ///
+  /// # Returns
+  ///
+  /// A list of projects found. Platforms that do not support hash-based
+  /// lookup return an empty list.
+  async fn request_projects_from_hashes(
+    &self,
+    hashes: &[String],
+    algorithm: &str,
+  ) -> Result<Vec<Project>>;
 }