Chen-period 陳 monk and the principal disciple of 真諦 Paramārtha (Zhēndì, 499–569). Lay surname Cáo 曹 (some sources Zhāng 張); resident at the Āyùwángsì 阿育王寺 in Jiànyè 建業 (Nanjing) and at temples in the Yángzhōu 揚都 region — hence the colophon of KR6o0110 giving him as 楊州智愷. Lifedates 518–568 (Chén Guāngdà 2 = 568), age 51 (per the Yínián lù 疑年錄 and the Xù gāosēng zhuàn 續高僧傳, T50n2060). The DILA authority record (A001283) treats him as identical with the figure also known as 慧愷 Huìkǎi (with the variant readings 凱公 and 凱師 as honorifics), although a few earlier sources distinguish them.
He served as Paramārtha’s principal Chinese amanuensis and editorial assistant. Through him pass several of the most consequential mid-sixth-century translations from the Yogācāra and Tathāgatagarbha corpora: the Shè dà-shèng lùn 攝大乘論 (Asaṅga’s Mahāyāna-saṃgraha), the Shè dà-shèng lùn shì 攝大乘論釋 (Vasubandhu’s commentary thereon), and the Dà-shèng qǐ-xìn lùn 大乘起信論 itself (KR6o0078) — though Paramārtha’s involvement in the actual production of the Chinese Qǐ-xìn lùn is now disputed by modern scholarship, which treats the text as more probably a sixth-century Chinese composition than a translation. Either way, Zhì-kǎi was at the heart of the textual culture that produced and circulated the work.
In the Kanripo corpus he is the author of the short KR6o0110 Qǐxìn lùn yīxīn èrmén dàyì 起信論一心二門大意 (Xùzàngjīng X45n754), which presents the Qǐxìn lùn’s “one mind, two gates” doctrine in compact aphoristic prose; if genuinely his, the text would represent the earliest commentary on the Qǐxìn tradition.
Sources: DILA Buddhist Person Authority A001283; Xù gāosēng zhuàn 續高僧傳 T50n2060; Yínián lù 疑年錄 49.