Not so much that it was unclear how they worked and more that I wasn't sure how they interacted with other runes because both Weave and Meal used unique terms.
Weave says that it interacts with runes that "directly create" light, but the runes that trigger it either "grant" light (Final Spark, Herd, Dawning, First Charge) or say that you "gain" light (Growth, Salvage, Dredge). Similarly, Meal triggers when a rune "upgrades" the Broodmother, but all of the runes that upgrade other cards say "increases light gain by [amount] for [card]" - I thought for a second that the Candle's energy cost reduction might count (because reducing the cost is an upgrade) but nope.
I think it'd really help clarity if all of the runes that "directly create" light were changed to say create instead of grant/gain and Meal was changed to something like "adds a temporary spider card when a rune increases this card's light gain" or something to that effect.