iOfficeAI/OfficeCLI · error · ArgumentException

path is empty — pass a relative skill file, e.g. reference/d

Error message

path is empty — pass a relative skill file, e.g. reference/decision-rules.md

What it means

Thrown by LoadSkillFile when the relativePath, after backslash-to-slash conversion and leading-slash trimming, is empty. Guards against a caller passing null, '', '/', or whitespace-only path. ArgumentException with an explicit hint to pass something like 'reference/decision-rules.md'.

Source

Thrown at src/officecli/Core/SkillInstaller.cs:290

            .OrderBy(rel => rel, StringComparer.OrdinalIgnoreCase)
            .ToList();
    }

    /// <summary>
    /// Return the text content of one bundled reference file inside a skill
    /// (e.g. "reference/decision-rules.md"). Shared by the CLI
    /// `load_skill &lt;name&gt; --path &lt;rel&gt;` command and the MCP
    /// `load_skill` tool's path= argument. Throws on unknown skill, path
    /// traversal, a binary asset (cannot ride the text channel), or a missing
    /// file.
    /// </summary>
    public static string LoadSkillFile(string skillName, string relativePath)
    {
        if (!SkillMap.TryGetValue(skillName, out var folder))
            throw new ArgumentException($"Unknown skill: {skillName}. Available: {KnownSkillsList()}");
        var rel = (relativePath ?? "").Replace('\\', '/').TrimStart('/');
        if (rel.Length == 0)
            throw new ArgumentException("path is empty — pass a relative skill file, e.g. reference/decision-rules.md");
        // Contain to the skill folder: reject traversal and current-dir segments.
        if (rel.Split('/').Any(seg => seg is ".." or "."))
            throw new ArgumentException($"Invalid skill file path: {relativePath}");
        if (BinarySkillExtensions.Contains(Path.GetExtension(rel)))
            throw new ArgumentException(
                $"'{rel}' is a binary asset and cannot be served over the text channel. " +
                $"Install the skill to get it on disk: officecli skills install {skillName}");
        var content = LoadEmbeddedResource($"skills/{folder}/{rel}");
        if (content == null)
            throw new ArgumentException(
                $"Skill file not found: {rel}. List available files via the manifest at the end of: " +
                $"officecli load_skill {skillName}");
        return content;
    }

    /// <summary>
    /// Build the "Reference files" manifest appended to a SKILL.md. Deep trees
    /// (≥ 3 path segments, e.g. a 52-directory style library) collapse to one

View on GitHub (pinned to 1ced45e900)

Solutions

Pass a non-empty relative path such as 'reference/decision-rules.md'.
Get valid paths from the manifest appended to load_skill output, or from ListSkillFiles.
Check the path variable is non-empty before calling.

Example fix

// before
officecli load_skill morph-ppt --path ""
// after
officecli load_skill morph-ppt --path reference/decision-rules.md

Defensive patterns

Strategy: validation

Validate before calling

var rel = (relativePath ?? string.Empty).Replace('\\', '/').TrimStart('/');
if (string.IsNullOrEmpty(rel))
    throw new ArgumentException("path is empty — pass a relative skill file");
var text = SkillInstaller.LoadSkillFile(skillName, rel);

Try / catch

try { var text = SkillInstaller.LoadSkillFile(skillName, relativePath); }
catch (ArgumentException ex) when (ex.Message.Contains("path is empty"))
{ /* prompt for a non-empty relative path */ }

Prevention

Always pass a concrete relative path like 'reference/foo.md'.
Guard MCP path= argument against null/empty before calling.
Fetch valid paths from the load_skill manifest or ListSkillFiles.

When it happens

Trigger: Calling load_skill with --path omitted, empty, '/', or '\', or an MCP path= of null/empty. The check fires after the skill-name check passes.

Common situations: MCP caller omits the path field, CLI user forgets the --path value, or a script passes an untrimmed variable that resolves to empty.

Related errors

AI-assisted analysis of iOfficeAI/OfficeCLI@1ced45e900 (2026-08-13). Data as JSON: /api/errors/4b3873c9cc45382c. Report an issue: GitHub.