wavetermdev/waveterm · error

missing filename parameter

Error message

missing filename parameter

What it means

read_text_file requires a "filename" parameter identifying the file to read. If the input object unmarshals fine but leaves Filename empty, parsing stops with this error because there is nothing to open.

Source

Thrown at pkg/aiusechat/tools_readfile.go:44

	Origin   *string `json:"origin"` // "start" or "end", defaults to "start"
	Offset   *int    `json:"offset"` // lines to skip, defaults to 0
	Count    *int    `json:"count"`  // number of lines to read, defaults to DefaultLineCount
	MaxBytes *int    `json:"max_bytes"`
}

func parseReadTextFileInput(input any) (*readTextFileParams, error) {
	result := &readTextFileParams{}

	if input == nil {
		return nil, fmt.Errorf("input is required")
	}

	if err := utilfn.ReUnmarshal(result, input); err != nil {
		return nil, fmt.Errorf("invalid input format: %w", err)
	}

	if result.Filename == "" {
		return nil, fmt.Errorf("missing filename parameter")
	}

	if result.Origin == nil {
		origin := "start"
		result.Origin = &origin
	}

	if *result.Origin != "start" && *result.Origin != "end" {
		return nil, fmt.Errorf("invalid origin value '%s': must be 'start' or 'end'", *result.Origin)
	}

	if result.Offset == nil {
		offset := 0
		result.Offset = &offset
	}

	if *result.Offset < 0 {
		return nil, fmt.Errorf("offset must be non-negative, got %d", *result.Offset)

View on GitHub (pinned to a4447c1563)

Solutions

1. Include a non-empty "filename" key in the input object.
2. Rename "path"/"file" keys to "filename" for this tool.
3. Validate that the intended path string is non-empty before issuing the call.

Example fix

// before
{"input": {"path": "/tmp/a.txt"}}
// after
{"input": {"filename": "/tmp/a.txt"}}

if params["filename"] == "" || params["filename"] == nil {
    return errors.New("filename required")
}

func hasFilename(m map[string]any) bool {
    s, ok := m["filename"].(string)
    return ok && s != ""
}

params, err := parseReadTextFileInput(input)
if err != nil && err.Error() == "missing filename parameter" {
    // retry with {filename: intendedPath}
}

When it happens

Trigger: Calling read_text_file with an input object that omits "filename" or passes it as an empty string.

Common situations: Model-generated tool calls with typo'd keys ("file", "path"); agents confusing parameter names with the read_directory tool's "path"; empty variables interpolated into the call.

Understand the failure class

Background: "missing required argument" and "the following required arguments were not provided": what required-argument errors mean and how to fix them — this error's family across 20 libraries.

Related errors

• input is required
• invalid origin value '%s': must be 'start' or 'end'
• offset must be non-negative, got %d
• count must be at least 1, got %d
• integer overflow

AI-assisted analysis of wavetermdev/waveterm@a4447c1563 (2026-09-01). Data as JSON: /api/errors/4bbeecf95d1e7b46. Report an issue: GitHub.