anthropic.internal._headers
(internal) Defaults, then the caller's headers, then auth. User headers come FIRST so `anthropic-beta` (and `anthropic-dangerous-direct-browser-access`, which the WASM playground needs) are reachable and `anthropic-version` is overridable; `x-api-key` is applied last so a stray header cannot break authentication.
Reference version
Signature
function anthropic.internal._headers(
c: anthropic.Client,
preview: bool = …
) -> map<string, string> throws baml.errors.Io | baml.errors.ParseError | ai.errors.InvalidRequest
(internal) Defaults, then the caller's headers, then auth. User headers come FIRST so
anthropic-beta (and anthropic-dangerous-direct-browser-access, which the
WASM playground needs) are reachable and anthropic-version is overridable;
x-api-key is applied last so a stray header cannot break authentication.
Source:<builtin>/anthropic/ns_internal/messages.bamlbytes 30251–30734