Add MS 29987 is a mediaeval Tuscan musical manuscript dating from the late fourteenth or early fifteenth century, held in the British Library in London.

[1][2] The manuscript appears to have belonged to the de' Medici family of the Republic of Florence in the fifteenth century – the first folio has the de' Medici arms in red, gold, blue and green;[3]: 7–8  these are in the "augmented" form granted by Louis XI in 1465, with the arms of France in the upper central ball.

On 8 April 1876 it was acquired by the British Museum from the antiquarian bookseller Bernard Quaritch;[5] it was catalogued as item 29987 of the Additional manuscripts series.

[3]: 9  Of these, 45 are ballate, 35 or 36 (if a fragment is counted) are madrigals, 15 are instrumental pieces under the general title of "istampitta" or estampie, 8 are cacce and 3 are virelais.

There are also a motet and a "Chançonete tedesce" or canzonetta tedesca, and 7 liturgical works, kyrie, gloria, credo, antiphon, two sequences and a hymn; the last piece is untexted, but may be a madrigal.