--max-tools must be a non-negative integer (0 means use temp

Error message

--max-tools must be a non-negative integer (0 means use template default)

What it means

validateReviewOptions requires --max-tools to be >= 0; 0 is allowed and means 'use the template default'. Negative values are rejected. Additionally, a positive value below the minimum of 50 is not an error but is clamped up to 50 with a stderr notice.

Source

Thrown at cmd/opencodereview/shared_flags.go:141

func validateReviewOptions(opts *reviewOptions) error {
	if err := validateDiffMode(opts.from, opts.to, opts.commit); err != nil {
		return err
	}
	if opts.preview && opts.resume != "" {
		return fmt.Errorf("--preview and --resume cannot be used together")
	}
	if err := validateAudience(opts.audience); err != nil {
		return err
	}
	normalizedFormat, err := validateOutputFormat(opts.outputFormat)
	if err != nil {
		return err
	}
	opts.outputFormat = normalizedFormat
	const minMaxTools = 50
	if opts.maxTools < 0 {
		return fmt.Errorf("--max-tools must be a non-negative integer (0 means use template default)")
	}
	if opts.maxTools > 0 && opts.maxTools < minMaxTools {
		fmt.Fprintf(os.Stderr, "[ocr] --max-tools %d is below minimum %d, using %d\n", opts.maxTools, minMaxTools, minMaxTools)
		opts.maxTools = minMaxTools
	}
	if opts.maxGitProcs < 0 {
		return fmt.Errorf("--max-git-procs must be a non-negative integer (0 means use default 16)")
	}
	if opts.maxTokens < 0 {
		return fmt.Errorf("--max-tokens must be a non-negative integer (0 means use configured or template default)")
	}
	if opts.maxTokensBudget < 0 {
		return fmt.Errorf("--max-tokens-budget must be a non-negative integer (0 means unlimited)")
	}
	if opts.effort != "" {
		if _, err := template.ParseEffort(opts.effort); err != nil {
			return fmt.Errorf("--effort: %w", err)
		}

View on GitHub (pinned to 5cf97d0d15)

Solutions

Pass a non-negative integer: --max-tools 0 to use the template default
Clamp in your script: MAX_TOOLS=$(( value < 0 ? 0 : value ))
Fix the calculation producing the negative budget
Omit the flag entirely to get the default

Example fix

// before
ocr review --from main --to HEAD --max-tools -5
// after
ocr review --from main --to HEAD --max-tools 0   # 0 = template default

Defensive patterns

Strategy: validation

Validate before calling

case "$MAX_TOOLS" in ''|*[!0-9]*) echo "max-tools must be a non-negative integer, got: $MAX_TOOLS"; exit 2;; esac

Type guard

function isNonNegativeInt(v) { return Number.isInteger(v) && v >= 0; }

Try / catch

ocr review --max-tools "$MAX_TOOLS" 2>err.log || { grep -q 'max-tools must be a non-negative' err.log && ocr review --max-tools 0; }

Prevention

Clamp computed budgets: v < 0 ? 0 : v
Remember 0 means 'template default', not 'disabled'
Validate config files that feed numeric flags
Note values 1-49 are silently raised to 50 with a stderr warning

When it happens

Trigger: Passing --max-tools -1 (or any negative number) to review — the opts.maxTools < 0 branch in validateReviewOptions, invoked from the review command's anonymous caller.

Common situations: Scripts computing the value via arithmetic that can go negative (e.g. $(($BUDGET - $USED))); config files with placeholder negatives; misunderstanding 0 as 'disable' when it actually means 'default'.

Related errors

AI-assisted analysis of alibaba/open-code-review@5cf97d0d15 (2026-09-02). Data as JSON: /api/errors/ce5c72d837d4c3a7. Report an issue: GitHub.