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+#### 💬 Fair use
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+
+To ensure service availability, shared instance has a few limitations:
+  * Images are cached for 1 hour
+    * Rendered metrics **won't be updated** during this time window when queried
+    * You can manually update rendering again your metrics on [metrics.lecoq.io](https://metrics.lecoq.io)
+  * A rate limiter is enabled to prevent denial of service (it doesn't affect already cached metrics)
+  * Some plugins may not be available
+
+Service is provided free of charge, so please be gentle with it 🙂