I'm using beets for my music library. However, it seems like queries for very big releases (25+ mediums) don't return all the requested information. After looking after it in https://github.com/beetbox/beets/issues/3308 it turns out that the problem is on MusicBrainz' side: when I check for a very big release (80 cds) https://musicbrainz.org/ws/2/release/9c5c043e-bc69-4edb-81a4-1aaf9c81e6dc?inc=media+recordings+release-groups+labels+artist-credits+aliases+recording-level-rels+work-rels+work-level-rels+artist-rels which is the equivalent of musicbrainzngs.get_release_by_id(albumid,RELEASE_INCLUDES) with the same RELEASE_INCLUDES it does not show any work relationships, even if we requested it:

<track id="19fbfd3b-92b6-3c1b-b7a6-703048a128a7">
<position>1</position>
<number>1</number>
<title>Goldberg-Variationen, BWV 988: Aria</title>
<length>113893</length>
<artist-credit>
<name-credit>
<artist id="24f1766e-9635-4d58-a4d4-9413f9f98a4c">
<name>Johann Sebastian Bach</name>
<sort-name>Bach, Johann Sebastian</sort-name>
<disambiguation>German Baroque period composer & musician</disambiguation>
<alias-list count="40">
<alias sort-name="Bach" type="Search hint" type-id="1937e404-b981-3cb7-8151-4c86ebfc8d8e">Bach</alias>
</alias-list>
</artist>
</name-credit>
</artist-credit>
<recording id="d57d7065-020f-4648-b1ca-12c9ba72f78d">
<title>Goldberg Variations, BWV 988: Aria</title>
<length>113786</length>
<artist-credit>
<name-credit>
<artist id="7002bf88-1269-4965-a772-4ba1e7a91eaa">
<name>Glenn Gould</name>
<sort-name>Gould, Glenn</sort-name>
<disambiguation>pianist</disambiguation>
<alias-list count="3">
<alias type="Search hint" type-id="1937e404-b981-3cb7-8151-4c86ebfc8d8e" sort-name="1)Glenn Gould">1)Glenn Gould</alias>
</alias-list>
</artist>
</name-credit>
</artist-credit>
<alias-list count="4">
<alias sort-name="Aria from Goldberg Variations BWV 988 (1955 recording) - Johann Sebastian Bach">Aria from Goldberg Variations BWV 988 (1955 recording) - Johann Sebastian Bach</alias>
</alias-list>
</recording>
</track>{{}}

As can be seen, the artists and their aliases are there, but that's pretty much all. Also, I would have expected recording dates to be there as well as instruments (Gould as pianist).

If we now look at https://musicbrainz.org/ws/2/release/db49c56b-7e11-4cbc-8fcc-577a031e8cd6?inc=media+recordings+release-groups+labels+artist-credits+aliases+recording-level-rels+work-rels+work-level-rels+artist-rels which is a release that contains exactly the same recordings (it's pretty much the first medium of the release above) but only one CD and requested with the same options. There, the first track is much more detailed:

<track id="73e69279-d8c2-3a26-89ae-dc67535be2ee">
<position>1</position>
<number>A1</number>
<length>112693</length>
<artist-credit>
<name-credit>
<artist id="24f1766e-9635-4d58-a4d4-9413f9f98a4c">
<name>Johann Sebastian Bach</name>
<sort-name>Bach, Johann Sebastian</sort-name>
<disambiguation>German Baroque period composer & musician</disambiguation>
<alias-list count="40">
<alias sort-name="Bach" type-id="894afba6-2816-3c24-8072-eadb66bd04bc" type="Artist name">Bach</alias>
</alias-list>
</artist>
</name-credit>
</artist-credit>
<recording id="d57d7065-020f-4648-b1ca-12c9ba72f78d">
<title>Goldberg Variations, BWV 988: Aria</title>
<length>113786</length>
<artist-credit>
<name-credit>
<artist id="7002bf88-1269-4965-a772-4ba1e7a91eaa">
<name>Glenn Gould</name>
<sort-name>Gould, Glenn</sort-name>
<disambiguation>pianist</disambiguation>
<alias-list count="3">
<alias type-id="1937e404-b981-3cb7-8151-4c86ebfc8d8e" type="Search hint" sort-name="1)Glenn Gould">1)Glenn Gould</alias>
</alias-list>
</artist>
</name-credit>
</artist-credit>
<alias-list count="4">
<alias sort-name="Aria from Goldberg Variations BWV 988 (1955 recording) - Johann Sebastian Bach">Aria from Goldberg Variations BWV 988 (1955 recording) - Johann Sebastian Bach</alias>
</alias-list>
<relation-list target-type="artist">
<relation type-id="5c0ceac3-feb4-41f0-868d-dc06f6e27fc0" type="producer">
<target>64078387-5ff3-43d1-b203-38f98ef74c24</target>
<direction>backward</direction>
<artist id="64078387-5ff3-43d1-b203-38f98ef74c24">
<name>Howard H. Scott</name>
<sort-name>Scott, Howard H.</sort-name>
<disambiguation>classical music producer</disambiguation>
</artist>
</relation>
<relation type="instrument" type-id="59054b12-01ac-43ee-a618-285fd397e461">
<target>7002bf88-1269-4965-a772-4ba1e7a91eaa</target>
<direction>backward</direction>
<begin>1955-06-10</begin>
<end>1955-06-16</end>
<ended>true</ended>
<attribute-list>
<attribute type-id="b3eac5f9-7859-4416-ac39-7154e2e8d348">piano</attribute>
</attribute-list>
<artist id="7002bf88-1269-4965-a772-4ba1e7a91eaa">
<name>Glenn Gould</name>
<sort-name>Gould, Glenn</sort-name>
<disambiguation>pianist</disambiguation>
</artist>
</relation>
</relation-list>
<relation-list target-type="work">
<relation type-id="a3005666-a872-32c3-ad06-98af558e99b0" type="performance">
<target>6934e59b-e82c-3050-b0cf-70907db1f1a3</target>
<begin>1955-06-10</begin>
<end>1955-06-16</end>
<ended>true</ended>
<work id="6934e59b-e82c-3050-b0cf-70907db1f1a3">
<title>Goldberg-Variationen, BWV 988: Aria</title>
<language>zxx</language>
<language-list>
<language>zxx</language>
</language-list>
<relation-list target-type="artist">
<relation type-id="d59d99ea-23d4-4a80-b066-edca32ee158f" type="composer">
<target>24f1766e-9635-4d58-a4d4-9413f9f98a4c</target>
<direction>backward</direction>
<artist id="24f1766e-9635-4d58-a4d4-9413f9f98a4c">
<name>Johann Sebastian Bach</name>
<sort-name>Bach, Johann Sebastian</sort-name>
<disambiguation>German Baroque period composer & musician</disambiguation>
</artist>
</relation>
</relation-list>
<relation-list target-type="work">
<relation type-id="ca8d3642-ce5f-49f8-91f2-125d72524e6a" type="parts">
<target>1d51e560-2a59-4e97-8943-13052b6adc03</target>
<ordering-key>1</ordering-key>
<direction>backward</direction>
<work id="1d51e560-2a59-4e97-8943-13052b6adc03">
<title>Goldberg-Variationen, BWV 988</title>
</work>
</relation>
<relation type-id="51975ed8-bbfa-486b-9f28-5947f4370299" type="arrangement">
<target>8b683c5c-74d7-4be4-9157-0b706f2f904a</target>
<work id="8b683c5c-74d7-4be4-9157-0b706f2f904a">
<title>Goldberg-Variationen, BWV 988: Aria</title>
<disambiguation>catch-all for arrangements</disambiguation>
</work>
</relation>
</relation-list>
</work>
</relation>
</relation-list>
</recording>
</track>
{{}}

As we can see, it contains the work title and other relations, composer, arrangements, performers and their instrument, producer, recording date etc. It is the same recording, we asked for the same information but get much more information for a smaller release.

Do you have an idea why this happens? Does the server have a cap on the amount of data he can send in one go? Do you know how we can circumvent the problem?