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Claude Code v2.1.246

Request bodies can be gzipped with random padding to hide their length

Under the hood
Useful2 Signal4
Internals

Request bodies can be gzipped with random padding so their compressed size hides the real length.

What

A new helper can compress an outbound request body, first appending a newline and between 0 and 256 random spaces or tabs so the compressed size does not reveal the exact payload length, and setting Content-Encoding: gzip. It does nothing unless a compression-decision function is supplied at the call site and picks gzip for that URL; otherwise the request is sent as before.

Details
  • The padding is added before compression, so it affects the transmitted size rather than the content the server parses.
Evidence

{ body: EP(i), headers: { "Content-Encoding": "gzip" } }

Strings lifted out of the shipped bundle, so the claim above can be checked against them.

Related

Other releases about the same thing. Found by shared names or similar wording; neither means one caused the other.

See this entry in the whole of v2.1.246 →