What is W3C_I18n-Checker?

Monitor it before deciding. W3C_I18n-Checker has not been categorized, so there is no established behavior profile to rely on. Review which pages it requests and how often, then block it if the traffic is excessive or targets content you would not share with an unknown bot. For context, 6% of the top websites we track currently have robots.txt rules for W3C_I18n-Checker.

Yes. W3C_I18n-Checker is expected to follow robots.txt rules, so a disallow rule is the appropriate first step. Automatic Robots.txt can add and maintain that rule, while Agent Analytics lets you verify whether W3C_I18n-Checker respects it.

Unknown. W3C_I18n-Checker has no established scope, so monitor what it requests. Repeated attempts to reach login or admin paths are a reason to investigate or block it.

Agent Analytics tracks W3C_I18n-Checker visits in real time. You can also check your server logs for requests whose user-agent string contains "W3C_I18n-Checker". Record the paths it requests and how often because no reliable behavior profile exists yet. Because W3C_I18n-Checker does not publish a verification method, any client can claim its identity and a log match is only a clue.

W3C_I18n-Checker's purpose has not yet been identified. Until it is categorized or its operator explains it, its behavior on your site is the best evidence of its intent.