Rishi: Bhṛgu-lineage (traditional attribution via internal mention of Bhṛgavaḥ); in Śukla-Yajurvedic liturgical use, treated as a received ṛṣi-tradition rather than a single author
Devata: Agni (as Hotṛ and first-established fire)
Chandas: Triṣṭubh (by RV-parallel cadence and length; confirmable by full metrical scan in RV source)
This (Agni) was here established first by the Ordainers: the Hotṛ, most meet for sacrifice, worthy of praise in the rites; whom, as one winning substance, the Bhṛgus caused to shine forth in the woods—bright, all-pervading—unto each and every clan.