fix links

Author: rtso

apps/nextra/pages/en/build/indexer/indexer-sdk/documentation.mdx

@@ -30,7 +30,7 @@ Each `Step` has an input and output, and the output of each `Step` is connected
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 ## When to use the Indexer SDK
-The Indexer SDK is useful when you want to index a custom contract or you realize you need a new kind of data that isn't available in the [Indexer API](../indexer-api.mdx).
+The Indexer SDK is useful when you want to index a custom contract or you realize you need a new kind of data that isn't available in the [Indexer API](../aptos-hosted.mdx).
 
 The general flow to write a custom processor with the Indexer SDK is:
 1. Define your database schema