What causes "invalid env entry %q: must be in KEY=VALUE format" in alibaba/open-code-review?

Write each entry as KEY=VALUE, e.g. '["DEBUG=1"]'

invalid env entry %q: must be in KEY=VALUE format

Error message

invalid env entry %q: must be in KEY=VALUE format

What it means

Raised after the env JSON array parses: each element must be a KEY=VALUE string. An entry with no '=' (idx <= 0 also rejects empty key, i.e. '=VALUE') cannot be turned into an environment variable for the MCP server subprocess, so the setter fails with the offending entry quoted.

Source

Thrown at cmd/opencodereview/config_cmd.go:881

		if value == "" {
			return fmt.Errorf("MCP server command cannot be empty")
		}
		entry.Command = value
	case "args":
		var args []string
		if err := json.Unmarshal([]byte(value), &args); err != nil {
			return fmt.Errorf("invalid JSON array for %s: %w", key, err)
		}
		entry.Args = args
	case "env":
		var env []string
		if err := json.Unmarshal([]byte(value), &env); err != nil {
			return fmt.Errorf("invalid JSON array for %s: %w", key, err)
		}
		for _, e := range env {
			idx := strings.Index(e, "=")
			if idx <= 0 {
				return fmt.Errorf("invalid env entry %q: must be in KEY=VALUE format", e)
			}
		}
		entry.Env = env
	case "url":
		if value == "" {
			return fmt.Errorf("MCP server URL cannot be empty")
		}
		parsed, err := url.Parse(value)
		if err != nil {
			return fmt.Errorf("invalid MCP server URL %q: %w", value, err)
		}
		if parsed.Scheme != "http" && parsed.Scheme != "https" {
			return fmt.Errorf("MCP server URL must use http or https scheme, got %q", parsed.Scheme)
		}
		if parsed.Host == "" {
			return fmt.Errorf("MCP server URL %q must include a host", value)
		}
		entry.URL = value

View on GitHub (pinned to 5cf97d0d15)

Solutions

Write each entry as KEY=VALUE, e.g. '["DEBUG=1"]'
To pass through an existing variable, read it in the shell first: '["TOKEN='$TOKEN'"]'
Remove empty or name-only entries from the array

Example fix

// before
ocr config set mcp_servers.fs.env '["DEBUG"]'
// after
ocr config set mcp_servers.fs.env '["DEBUG=1"]'

Defensive patterns

Strategy: validation

Validate before calling

for _, e := range entries {
	if i := strings.Index(e, "="); i <= 0 {
		return fmt.Errorf("entry %q must be KEY=VALUE", e)
	}
}

Type guard

func isValidEnvEntry(e string) bool {
	return strings.Index(e, "=") > 0
}

Try / catch

if err := setMCPServerValue(cfg, key, value); err != nil {
	fmt.Fprintf(os.Stderr, "config set failed: %v\n", err)
	os.Exit(1)
}

Prevention

Include '=' in every entry, with a non-empty key before it
Expand existing variables in the shell before building the array
Trim the array of empty strings from copy-paste

When it happens

Trigger: Calling setMCPServerValue with field "env" where any array element lacks '=', e.g. '["DEBUG"]', '["=1"]', or '[""]'.

Common situations: Listing variable names only (expecting the tool to read them from the parent environment), typos dropping the '=', or an empty string left in the array from copy-paste.

Related errors

AI-assisted analysis of alibaba/open-code-review@5cf97d0d15 (2026-09-02). Data as JSON: /api/errors/bd69ddb373fb536f. Report an issue: GitHub.