lima-vm/lima · error

template does not define param %#q

Error message

template does not define param %#q

What it means

BuildParamExpressions validates each NAME=VALUE parameter against the set of parameters the target template actually defines (allowedParams). This error is returned when the NAME is not a defined param in the template, so the override would have no effect or produce an invalid yq expression.

Source

Thrown at cmd/limactl/editflags/editflags.go:193

		hostPort, guestPort, isStatic, err := ParsePortForward(spec)
		if err != nil {
			return "", err
		}
		ports[i] = fmt.Sprintf(`{"guestPort": %q, "hostPort": %q, "static": %v}`, guestPort, hostPort, isStatic)
	}
	expr := fmt.Sprintf(".portForwards += [%s]", strings.Join(ports, ","))
	return expr, nil
}

func BuildParamExpressions(params []string, allowedParams map[string]string) ([]string, error) {
	exprs := make([]string, len(params))
	for i, param := range params {
		key, value, ok := strings.Cut(param, "=")
		if !ok {
			return nil, fmt.Errorf("invalid parameter %#q, expected NAME=VALUE", param)
		}
		if _, ok := allowedParams[key]; !ok {
			return nil, fmt.Errorf("template does not define param %#q", key)
		}
		exprs[i] = fmt.Sprintf(".param[%q] = %q", key, value)
	}
	return exprs, nil
}

func buildMountListExpression(ss []string) (string, error) {
	mounts := make([]string, len(ss))
	for i, s := range ss {
		writable := strings.HasSuffix(s, ":w")
		loc, err := localpathutil.Expand(strings.TrimSuffix(s, ":w"))
		if err != nil {
			return "", err
		}
		mounts[i] = fmt.Sprintf(`{"location": %q, "mountPoint": %q, "writable": %v}`, loc, loc, writable)
	}
	expr := fmt.Sprintf("[%s]", strings.Join(mounts, ","))
	return expr, nil

View on GitHub (pinned to dd909d0973)

Solutions

1. Inspect the template and use exactly its declared param names (e.g. --param cpus=4)
2. Fix typos in the parameter NAME
3. Use the appropriate generic flags (e.g. --cpus) instead of --param when the template has no such param
4. Update to a template version that still defines the param

Example fix

// before
limactl create template://_default --param cpuCount=4
// after
limactl create template://_default --param cpus=4

for _, p := range params {
	key, _, _ := strings.Cut(p, "=")
	if _, ok := allowedParams[key]; !ok {
		return fmt.Errorf("template defines no param %q; allowed: %v", key, keysOf(allowedParams))
	}
}

func paramAllowed(key string, allowed map[string]string) bool {
	_, ok := allowed[key]
	return ok
}

exprs, err := editflags.BuildParamExpressions(params, allowedParams)
if err != nil {
	return fmt.Errorf("--param rejected: %w (check the template's defined params)", err)
}

When it happens

Trigger: Calling BuildParamExpressions with a key absent from allowedParams, e.g. --param cpuCount=4 against a template whose params only define 'cpus'; also happens when passing params to a template with no params at all.

Common situations: Typos in parameter names (cpus vs cpuCount vs cpu); using params from one template with another template; version drift where a template renamed or removed a param; forgetting the template:// prefix format differences.

Related errors

• invalid parameter %#q, expected NAME=VALUE
• invalid value for static parameter: %#q
• invalid parameter %#q, expected `static=` followed by a bool
• invalid value for number of cpus, must be >= 0
• instance %#q is stopped, run `limactl start %s` to start the

AI-assisted analysis of lima-vm/lima@dd909d0973 (2026-09-01). Data as JSON: /api/errors/4e0c989766874904. Report an issue: GitHub.