CoplayDev/unity-mcp · error · InvalidOperationException

GitHub returned a truncated directory tree (incomplete snaps

Error message

GitHub returned a truncated directory tree (incomplete snapshot). Sync was aborted to prevent accidental deletion of valid local files.

What it means

GitHub's recursive tree API sets truncated=true when the tree exceeds its entry/size limits. SkillSyncService aborts the sync on purpose: with an incomplete file list, the deletion phase of ApplyPlan would treat every omitted remote file as a local file to delete, destroying valid files.

Source

Thrown at MCPForUnity/Editor/Setup/SkillSyncService.cs:192

            return true;
        }

        private static RemoteSnapshot FetchRemoteSnapshot(GitHubRepoInfo repoInfo, string branch, string subdir, Action<string> log)
        {
            using var client = CreateGitHubClient();
            var commitSha = FetchBranchHeadCommitSha(client, repoInfo, branch, log);
            var treeApiUrl = BuildTreeApiUrl(repoInfo, commitSha);
            log?.Invoke($"Fetching remote directory tree at commit {ShortCommit(commitSha)}...");
            var json = DownloadString(client, treeApiUrl);
            var treeResponse = JsonUtility.FromJson<GitHubTreeResponse>(json);
            if (treeResponse == null || treeResponse.tree == null)
            {
                throw new InvalidOperationException("Failed to parse GitHub directory tree response.");
            }

            if (treeResponse.truncated)
            {
                throw new InvalidOperationException(
                    "GitHub returned a truncated directory tree (incomplete snapshot). " +
                    "Sync was aborted to prevent accidental deletion of valid local files.");
            }

            var normalizedSubdir = NormalizeRemotePath(subdir);
            var subdirPrefix = string.IsNullOrEmpty(normalizedSubdir) ? string.Empty : $"{normalizedSubdir}/";
            var remoteFiles = new Dictionary<string, string>(StringComparer.Ordinal);

            foreach (var entry in treeResponse.tree)
            {
                if (!string.Equals(entry.type, "blob", StringComparison.Ordinal))
                {
                    continue;
                }

                var remotePath = NormalizeRemotePath(entry.path);
                if (string.IsNullOrEmpty(remotePath))
                {

View on GitHub (pinned to c21bf496bc)

Solutions

1. Reduce the number of files under the synced directory.
2. Sync a narrower subdirectory if possible.
3. Move large/binary assets out of the skill directory.
4. If you control the repo, run a tree-size check and prune before syncing.

When it happens

Trigger: The synced subdirectory (.claude/skills/unity-mcp-skill) or the whole repo tree is large enough that GitHub truncates the recursive listing (typically tens of thousands of entries or a multi-MB response).

Common situations: Monorepo where the skill dir sits alongside huge generated output; the directory accumulated many assets over time; syncing the entire repo tree rather than a narrow subdir.

Related errors

• Failed to parse GitHub directory tree response.
• Failed to resolve branch head commit SHA for: {branch}
• GitHub request failed: {(int)response.StatusCode} {response.
• fal submit returned no request_id: {truncated_response}
• fal {phase} failed (status={res?.Status}): {detail}

AI-assisted analysis of CoplayDev/unity-mcp@c21bf496bc (2026-08-13). Data as JSON: /api/errors/eb5e80f846cf092c. Report an issue: GitHub.