Hi Nick ! Any updates concerning the limitations of input queries ? I just saw it’s now possible to use functions with javascript and i would love to use functions on my app 
Topic summary
Product metafields in a Shopify Function input query returned null, while the same metafields worked in GraphiQL and for DiscountNode. Root cause: platform limits—initially a 1 kB metafield value cap, plus input query size ≤ 3000 bytes and complexity cost 30—causing oversized product metafield values to resolve to null.
Shopify staff clarified the likely hit was the 1 kB metafield value limit and asked about the use case. The app stores date-based discount tables in a product metafield (custom product data), which can span months and exceed limits. The developer argued hard limits are too restrictive given the 5 ms function runtime cap and suggested warnings instead of strict caps.
Community feedback requested higher limits (e.g., 10 kB). A later update noted the metafield value limit was increased to 10,000 bytes per the docs.
Despite this, some use cases (e.g., product bundle configurations) remain constrained—previously ~80 bundles with Scripts, now fewer than 10 with Functions. Status: partially mitigated by the 10 kB increase; ongoing concerns and no final resolution or alternative guidance provided.