diff --git a/lib/components/fabro-github/src/lib.rs b/lib/components/fabro-github/src/lib.rs
index 007d06c66..e46836b04 100644
--- a/lib/components/fabro-github/src/lib.rs
+++ b/lib/components/fabro-github/src/lib.rs
@@ -4,8 +4,8 @@ use base64::engine::general_purpose::STANDARD;
 use chrono::{DateTime, Utc};
 use fabro_redact::DisplaySafeUrl;
 use fabro_static::EnvVars;
+use fabro_types::PullRequestGithubDetail;
 use fabro_types::settings::run::MergeStrategy;
-use fabro_types::{GitHubRepositorySlug, PullRequestGithubDetail};
 use serde::Deserialize;
 use tokio::process::Command;
 
@@ -993,29 +993,6 @@ fn normalize_https_host_path(url: &str) -> String {
     }
 }
 
-/// Return the commit SHA at the head of a GitHub branch.
-///
-/// Returns `None` when GitHub responds with 404. GitHub also uses 404 to hide
-/// some private resources from credentials that cannot access them, so `None`
-/// means the branch was not observable rather than proving it does not exist.
-pub async fn branch_head_sha(
-    ctx: &GitHubContext<'_>,
-    owner: &str,
-    repo: &str,
-    branch: &str,
-) -> anyhow::Result<Option<String>> {
-    let repository = GitHubRepositorySlug::try_new(&format!("{owner}/{repo}"))
-        .ok_or_else(|| anyhow!("Invalid GitHub repository coordinate"))?;
-    let reader = GitHubRepositoryReader::open(ctx, &repository)
-        .await
-        .context("Failed to read remote branch head")?;
-    match reader.resolve_commit(&format!("heads/{branch}")).await {
-        Ok(sha) => Ok(Some(sha)),
-        Err(RepositoryReadError::NotFound { .. }) => Ok(None),
-        Err(error) => Err(anyhow::Error::new(error).context("Failed to read remote branch head")),
-    }
-}
-
 /// Check whether a GitHub App is installed for a specific repository.
 ///
 /// Uses the App JWT to query `GET /repos/{owner}/{repo}/installation`.
diff --git a/lib/components/fabro-github/tests/integration.rs b/lib/components/fabro-github/tests/integration.rs
index c99131393..006f997b3 100644
--- a/lib/components/fabro-github/tests/integration.rs
+++ b/lib/components/fabro-github/tests/integration.rs
@@ -2,7 +2,7 @@ use std::error::Error as _;
 
 use fabro_github::{
     GitHubAppCredentials, GitHubContext, GitHubCredentials, GitHubRepositoryReader,
-    InstallationToken, RepositoryReadError, branch_head_sha, close_pull_request,
+    InstallationToken, RepositoryReadError, close_pull_request,
     create_installation_access_token_for_pr, create_pull_request, enable_auto_merge,
     get_pull_request, merge_pull_request, resolve_authenticated_url, sign_app_jwt,
 };
@@ -464,27 +464,23 @@ async fn expired_installation_token_keeps_credential_error_source() {
 }
 
 #[fabro_macros::e2e_test(twin)]
-async fn branch_head_compatibility_wrapper_uses_repository_reader() {
+async fn branch_head_resolution_distinguishes_missing_from_present() {
     let twin = TwinGitHub::start(standard_app_state()).await;
     let credentials = github_credentials();
-    let context = GitHubContext::with_http_client(
-        &credentials,
-        &twin.base_url,
-        fabro_test::test_http_client(),
-    );
+    let reader = open_reader(&twin.base_url, &credentials).await.unwrap();
 
     assert_eq!(
-        branch_head_sha(&context, "acme", "widgets", "release")
-            .await
-            .unwrap(),
-        Some(HEAD_SHA.to_string())
-    );
-    assert_eq!(
-        branch_head_sha(&context, "acme", "widgets", "missing")
-            .await
-            .unwrap(),
-        None
+        reader.resolve_commit("heads/release").await.unwrap(),
+        HEAD_SHA
     );
+    // GitHub answers an absent branch with 404, which the reader reports as
+    // "not observable" rather than proving the branch does not exist.
+    assert!(matches!(
+        reader.resolve_commit("heads/missing").await,
+        Err(RepositoryReadError::NotFound {
+            operation: fabro_github::Operation::Revision,
+        })
+    ));
 
     twin.shutdown().await;
 }