`keybase pgp select` fails with `ERROR EOF`

This is what my GPG key structure looks like:

λ gpg --edit-key EB52DA9C02BA6FB4
Secret key is available.

sec  ed25519/EB52DA9C02BA6FB4
     created: 2016-02-27  expires: never       usage: SC  
     trust: ultimate      validity: ultimate
ssb  rsa4096/4389A7B2E16BD23A
     created: 2016-02-27  expires: never       usage: E   
ssb  rsa4096/9A09076581B27402
     created: 2016-02-27  expires: never       usage: S   
[ultimate] (1). nand nand (Git signing) <git@nand.wakku.to>
[ultimate] (2)  nand nand (Spam detection) <gpg-23a69d@nand.wakku.to>
[ultimate] (3)  nand nand (Alias) <nand@nand.wakku.to>
[ultimate] (4)  Niklas Haas (Private use) <niklas.haas@uni-ulm.de>

gpg> quit

Here is what happens when I try selecting this GPG key for use with keybase:

λ keybase pgp select
#    Algo   Key Id             Created   UserId
=    ====   ======             =======   ======
1    256?   EB52DA9C02BA6FB4             nand nand <git@nand.wakku.to>, nand nand <gpg-23a69d@nand.wakku.to>, nand nand <nand@nand.wakku.to>, Niklas Haas <niklas.haas@uni-ulm.de>
Choose a key: 1
<snip>

At this point, GPG asks me to enter the following keys in succession. The first three correspond to my master key, encryption key and signing key - but the fourth one confuses me. (It asks me for my master key a second time, and with a confused bit-size and TYPE?)

Finally, after inputting all of the passphrases correctly, my log ends with

<snip>
▶ ERROR EOF

More info:

λ keybase --version
keybase version 1.0.16
λ gpg --version
gpg (GnuPG) 2.1.13
libgcrypt 1.7.1
Copyright (C) 2016 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.

Home: /home/nand/.gnupg
Supported algorithms:
Pubkey: RSA, ELG, DSA, ECDH, ECDSA, EDDSA
Cipher: IDEA, 3DES, CAST5, BLOWFISH, AES, AES192, AES256, TWOFISH,
        CAMELLIA128, CAMELLIA192, CAMELLIA256
Hash: SHA1, RIPEMD160, SHA256, SHA384, SHA512, SHA224
Compression: Uncompressed, ZIP, ZLIB, BZIP2
λ cat /etc/os-release
NAME=Gentoo
ID=gentoo
PRETTY_NAME="Gentoo/Linux"
ANSI_COLOR="1;32"
HOME_URL="http://www.gentoo.org/"
SUPPORT_URL="http://www.gentoo.org/main/en/support.xml"
BUG_REPORT_URL="https://bugs.gentoo.org/"
λ equery u keybase
!!! No USE flags found for app-crypt/keybase-1.0.16
λ equery u go     
[ Legend : U - final flag setting for installation]
[        : I - package is installed with flag     ]
[ Colors : set, unset                             ]
 * Found these USE flags for dev-lang/go-1.6.2:
 U I
 - - gccgo : Enable bootstrapping using gccgo

Reproduce keybase pgp select with the shown key structure, keybase 1.0.16, GnuPG 2.1.13, and the listed Gentoo environment; inspect the PGP selection path reached by that command. Confirm the cause of the extra prompt and ERROR EOF, then verify that selecting the key completes successfully without the EOF failure.