Gzip compression of API request bodies, reducing bandwidth for large context uploads.
- Controlled by
yGd(): checksCLAUDE_CODE_GZIP_REQUEST_BODIESenv var first; if unset, falls back to thetengu_gzip_request_bodiesfeature flag (defaultfalse) - Only applies to requests whose target host is
api.anthropic.com(verified bywce()URL host check); Bedrock, Vertex, customANTHROPIC_BASE_URL, and any non-Anthropic endpoints are unaffected - When enabled, sets
compress: "gzip"on the outgoing fetch options object, instructing the underlying HTTP layer to gzip-encode the request body before transmission - When the request body is a string, a random whitespace suffix is appended before compression: a newline (
\n) followed by 0–256 randomly chosen space or tab characters; this adds entropy to the payload to improve compression ratio consistency across requests - No changes are made to response handling; response decompression was already in place
Feature-flagged (tengu_gzip_request_bodies, defaulting false). Can be force-enabled with CLAUDE_CODE_GZIP_REQUEST_BODIES=1.
(search for "CLAUDE_CODE_GZIP_REQUEST_BODIES", "tengu_gzip_request_bodies", yGd() call at the fetch wrapper, wce(l) host check at line ~161308)
Strings lifted out of the shipped bundle, so the claim above can be checked against them.
tengu_gzip_request_bodies Not enough to sayNothing here resolved what this flag was doing on this version, so nothing here should be read as on or off.
This account: no value returned · anonymous baseline: no value returned · compiled default in v2.1.199: off
These values were read against a different version of Claude Code, so treat them as the nearest reading available instead of one taken on this release.
Read once, for one account on one subscription tier, against v2.1.199. It isn't a statement about your account. What a flag value here can and cannot tell you
New in this build: tengu_gzip_request_bodies