diff --git a/.github/workflows/test-rust.yml b/.github/workflows/test-rust.yml
index 21e1bcb90c6..3a2c550443d 100644
--- a/.github/workflows/test-rust.yml
+++ b/.github/workflows/test-rust.yml
@@ -64,8 +64,14 @@ jobs:
       - name: Run Clippy with Bedrock auth
         run: cargo clippy -p litellm-core --all-targets --features bedrock-auth --locked -- -D warnings
 
+      - name: Run Clippy with Vertex auth
+        run: cargo clippy -p litellm-core --all-targets --features vertex-auth --locked -- -D warnings
+
       - name: Run Rust tests
         run: cargo test --workspace --locked
 
       - name: Run core tests with Bedrock auth
         run: cargo test -p litellm-core --features bedrock-auth --locked
+
+      - name: Run core tests with Vertex auth
+        run: cargo test -p litellm-core --features vertex-auth --locked
diff --git a/litellm-rust/Cargo.lock b/litellm-rust/Cargo.lock
index ce28f737334..502f8edb4ba 100644
--- a/litellm-rust/Cargo.lock
+++ b/litellm-rust/Cargo.lock
@@ -2,6 +2,15 @@
 # It is not intended for manual editing.
 version = 4
 
+[[package]]
+name = "android_system_properties"
+version = "0.1.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "819e7219dbd41043ac279b19830f2efc897156490d7fd6ea916720117ee66311"
+dependencies = [
+ "libc",
+]
+
 [[package]]
 name = "arc-swap"
 version = "1.9.2"
@@ -13,13 +22,13 @@ dependencies = [
 
 [[package]]
 name = "async-trait"
-version = "0.1.91"
+version = "0.1.89"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ae36dc4177970ef04fde5178d3e2429882def40e57a451f919c098f72baa6cec"
+checksum = "9035ad2d096bed7955a320ee7e2230574d28fd3c3a0f186cbea1ff3c7eed5dbb"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 3.0.0",
+ "syn 2.0.118",
 ]
 
 [[package]]
@@ -113,7 +122,7 @@ dependencies = [
  "bytes-utils",
  "fastrand",
  "http 1.4.2",
- "http-body 1.1.0",
+ "http-body 1.0.1",
  "percent-encoding",
  "pin-project-lite",
  "tracing",
@@ -193,7 +202,7 @@ dependencies = [
  "futures-core",
  "futures-util",
  "http 1.4.2",
- "http-body 1.1.0",
+ "http-body 1.0.1",
  "http-body-util",
  "percent-encoding",
  "pin-project-lite",
@@ -222,7 +231,7 @@ dependencies = [
  "hyper-util",
  "pin-project-lite",
  "rustls 0.21.12",
- "rustls 0.23.42",
+ "rustls 0.23.41",
  "rustls-native-certs",
  "rustls-pki-types",
  "tokio",
@@ -279,7 +288,7 @@ dependencies = [
  "http 0.2.12",
  "http 1.4.2",
  "http-body 0.4.6",
- "http-body 1.1.0",
+ "http-body 1.0.1",
  "http-body-util",
  "pin-project-lite",
  "pin-utils",
@@ -313,7 +322,7 @@ checksum = "221eaa237ddf1ca79b60d1372aad77e47f9c0ea5b3ce5099da8c61d027dc77b3"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.119",
+ "syn 2.0.118",
 ]
 
 [[package]]
@@ -340,7 +349,7 @@ dependencies = [
  "http 0.2.12",
  "http 1.4.2",
  "http-body 0.4.6",
- "http-body 1.1.0",
+ "http-body 1.0.1",
  "http-body-util",
  "itoa",
  "num-integer",
@@ -392,7 +401,7 @@ dependencies = [
  "bytes",
  "futures-util",
  "http 1.4.2",
- "http-body 1.1.0",
+ "http-body 1.0.1",
  "http-body-util",
  "hyper 1.10.1",
  "hyper-util",
@@ -427,7 +436,7 @@ dependencies = [
  "bytes",
  "futures-util",
  "http 1.4.2",
- "http-body 1.1.0",
+ "http-body 1.0.1",
  "http-body-util",
  "mime",
  "pin-project-lite",
@@ -456,9 +465,9 @@ dependencies = [
 
 [[package]]
 name = "bitflags"
-version = "2.13.1"
+version = "2.13.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b588b76d00fde79687d7646a9b5bdf3cc0f655e0bbd080335a95d7e96f3587da"
+checksum = "b4388bee8683e3d04af747c73422af53102d2bd24d9eadb6cbc100baef4b43f8"
 
 [[package]]
 name = "block-buffer"
@@ -478,6 +487,15 @@ dependencies = [
  "hybrid-array",
 ]
 
+[[package]]
+name = "bs58"
+version = "0.5.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "bf88ba1141d185c399bee5288d850d63b8369520c1eafc32a0430b5b6c287bf4"
+dependencies = [
+ "tinyvec",
+]
+
 [[package]]
 name = "bumpalo"
 version = "3.20.3"
@@ -492,9 +510,12 @@ checksum = "1fd0f2584146f6f2ef48085050886acf353beff7305ebd1ae69500e27c67f64b"
 
 [[package]]
 name = "bytes"
-version = "1.12.1"
+version = "1.12.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "fc652a48c352aef3ea3aed32080501cf3ef6ed5da78602a020c991775b0aff04"
+checksum = "8ae3f5d315924270530207e2a68396c3cc547f6dca3fbdca317cfb1a51edb593"
+dependencies = [
+ "serde",
+]
 
 [[package]]
 name = "bytes-utils"
@@ -508,9 +529,9 @@ dependencies = [
 
 [[package]]
 name = "cc"
-version = "1.3.0"
+version = "1.2.65"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c89588d05638b5b4594a3348a2d6c20277e43a7f5c5202b05cc56888475a47b8"
+checksum = "e228eec9be7c17ccb640b59b36a5cd805ea2a564a4c5e162c2f659fea30d3b96"
 dependencies = [
  "find-msvc-tools",
  "jobserver",
@@ -526,9 +547,9 @@ checksum = "9330f8b2ff13f34540b44e946ef35111825727b38d33286ef986142615121801"
 
 [[package]]
 name = "cfg_aliases"
-version = "0.2.2"
+version = "0.2.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f079e83a288787bcd14a6aea84cee5c87a67c5a3e660c30f557a3d24761b3527"
+checksum = "613afe47fcd5fac7ccf1db93babcb082c5994d996f20b8b159f2ad1658eb5724"
 
 [[package]]
 name = "chacha20"
@@ -541,6 +562,18 @@ dependencies = [
  "rand_core 0.10.1",
 ]
 
+[[package]]
+name = "chrono"
+version = "0.4.45"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1aa79e62e7697b8e29b513a68abacf485adcd1fe8284a4316c5ae868e6633327"
+dependencies = [
+ "iana-time-zone",
+ "num-traits",
+ "serde",
+ "windows-link",
+]
+
 [[package]]
 name = "cmake"
 version = "0.1.58"
@@ -556,6 +589,16 @@ version = "0.5.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "0c9ea0ac24bc397ab3c98583a3c9ba74fa56b09a4449bbe172b9b1ddb016027a"
 
+[[package]]
+name = "combine"
+version = "4.6.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ba5a308b75df32fe02788e748662718f03fde005016435c444eea572398219fd"
+dependencies = [
+ "bytes",
+ "memchr",
+]
+
 [[package]]
 name = "const-oid"
 version = "0.10.2"
@@ -624,6 +667,40 @@ dependencies = [
  "cmov",
 ]
 
+[[package]]
+name = "darling"
+version = "0.23.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "25ae13da2f202d56bd7f91c25fba009e7717a1e4a1cc98a76d844b65ae912e9d"
+dependencies = [
+ "darling_core",
+ "darling_macro",
+]
+
+[[package]]
+name = "darling_core"
+version = "0.23.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9865a50f7c335f53564bb694ef660825eb8610e0a53d3e11bf1b0d3df31e03b0"
+dependencies = [
+ "ident_case",
+ "proc-macro2",
+ "quote",
+ "strsim",
+ "syn 2.0.118",
+]
+
+[[package]]
+name = "darling_macro"
+version = "0.23.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ac3984ec7bd6cfa798e62b4a642426a5be0e68f9401cfc2a01e3fa9ea2fcdb8d"
+dependencies = [
+ "darling_core",
+ "quote",
+ "syn 2.0.118",
+]
+
 [[package]]
 name = "data-encoding"
 version = "2.11.0"
@@ -635,6 +712,9 @@ name = "deranged"
 version = "0.5.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "7cd812cc2bc1d69d4764bd80df88b4317eaef9e773c75226407d9bc0876b211c"
+dependencies = [
+ "serde_core",
+]
 
 [[package]]
 name = "digest"
@@ -666,7 +746,7 @@ checksum = "1ac70aa55017e108007fbaf5aa0f54b021c98f92ff8af59d42eda9da96e3dd4f"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.119",
+ "syn 2.0.118",
 ]
 
 [[package]]
@@ -675,6 +755,12 @@ version = "1.0.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "92773504d58c093f6de2459af4af33faa518c13451eb8f2b5698ed3d36e7c813"
 
+[[package]]
+name = "dyn-clone"
+version = "1.0.20"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d0881ea181b1df73ff77ffaaf9c7544ecc11e82fba9b5f27b262a3c73a332555"
+
 [[package]]
 name = "either"
 version = "1.16.0"
@@ -688,10 +774,20 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "877a4ace8713b0bcf2a4e7eec82529c029f1d0619886d18145fea96c3ffe5c0f"
 
 [[package]]
-name = "fastrand"
-version = "2.5.0"
+name = "errno"
+version = "0.3.14"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "da7c62ceae207dd37ea5b845da6a0696c799f85e97da1ab5b7910be3c1c80223"
+checksum = "39cab71617ae0d63f51a36d69f866391735b51691dbda63cf6f96d042b63efeb"
+dependencies = [
+ "libc",
+ "windows-sys 0.61.2",
+]
+
+[[package]]
+name = "fastrand"
+version = "2.4.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9f1f227452a390804cdb637b74a86990f2a7d7ba4b7d5693aac9b4dd6defd8d6"
 
 [[package]]
 name = "find-msvc-tools"
@@ -721,10 +817,24 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "42703706b716c37f96a77aea830392ad231f44c9e9a67872fa5548707e11b11c"
 
 [[package]]
-name = "futures-channel"
-version = "0.3.33"
+name = "futures"
+version = "0.3.32"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "262590f4fe6afeb0bc83be1daa64e52657fe185690a958af7f3ad0e92085c5ae"
+checksum = "8b147ee9d1f6d097cef9ce628cd2ee62288d963e16fb287bd9286455b241382d"
+dependencies = [
+ "futures-channel",
+ "futures-core",
+ "futures-io",
+ "futures-sink",
+ "futures-task",
+ "futures-util",
+]
+
+[[package]]
+name = "futures-channel"
+version = "0.3.32"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "07bbe89c50d7a535e539b8c17bc0b49bdb77747034daa8087407d655f3f7cc1d"
 dependencies = [
  "futures-core",
  "futures-sink",
@@ -732,44 +842,44 @@ dependencies = [
 
 [[package]]
 name = "futures-core"
-version = "0.3.33"
+version = "0.3.32"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2cd50c473c80f6d7c3670a752354b8e569b1a7cbfdc0419ec88e5edad85e0dc7"
+checksum = "7e3450815272ef58cec6d564423f6e755e25379b217b0bc688e295ba24df6b1d"
 
 [[package]]
 name = "futures-io"
-version = "0.3.33"
+version = "0.3.32"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4577ecaa3c4f96589d473f679a71b596316f6641bc350038b962a5daf0085d7a"
+checksum = "cecba35d7ad927e23624b22ad55235f2239cfa44fd10428eecbeba6d6a717718"
 
 [[package]]
 name = "futures-macro"
-version = "0.3.33"
+version = "0.3.32"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2d6d3cde68c518367be28956066ddfef33813991b77a55005a69dae04bf3b10b"
+checksum = "e835b70203e41293343137df5c0664546da5745f82ec9b84d40be8336958447b"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.119",
+ "syn 2.0.118",
 ]
 
 [[package]]
 name = "futures-sink"
-version = "0.3.33"
+version = "0.3.32"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e34418ac499d6305c2fb5ad0ed2f6ac998c5f8ca209b4510f7f94242c647e307"
+checksum = "c39754e157331b013978ec91992bde1ac089843443c49cbc7f46150b0fad0893"
 
 [[package]]
 name = "futures-task"
-version = "0.3.33"
+version = "0.3.32"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b231ed28831efb4a61a08580c4bc233ec56bc009f4cd8f52da2c3cb97df0c109"
+checksum = "037711b3d59c33004d3856fbdc83b99d4ff37a24768fa1be9ce3538a1cde4393"
 
 [[package]]
 name = "futures-util"
-version = "0.3.33"
+version = "0.3.32"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a77a90a256fce34da66415271e30f94ee91c57b04b8a2c042d9cf3220179deaa"
+checksum = "389ca41296e6190b48053de0321d02a77f32f8a5d2461dd38762c0593805c6d6"
 dependencies = [
  "futures-core",
  "futures-io",
@@ -804,6 +914,20 @@ dependencies = [
  "wasm-bindgen",
 ]
 
+[[package]]
+name = "getrandom"
+version = "0.3.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "899def5c37c4fd7b2664648c28120ecec138e4d395b459e5ca34f9cce2dd77fd"
+dependencies = [
+ "cfg-if",
+ "js-sys",
+ "libc",
+ "r-efi 5.3.0",
+ "wasip2",
+ "wasm-bindgen",
+]
+
 [[package]]
 name = "getrandom"
 version = "0.4.3"
@@ -811,11 +935,84 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "300e883d756b2e4ec94e02791f39b04b522276138852cfc41d9fb7e904106099"
 dependencies = [
  "cfg-if",
- "js-sys",
  "libc",
- "r-efi",
+ "r-efi 6.0.0",
  "rand_core 0.10.1",
- "wasm-bindgen",
+]
+
+[[package]]
+name = "google-cloud-auth"
+version = "1.12.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "4595b69c95c727ac896a4f2f16d0cdaa6f547de0bc5d64dbe9201487fc3226d5"
+dependencies = [
+ "async-trait",
+ "base64",
+ "bytes",
+ "chrono",
+ "google-cloud-gax",
+ "hex",
+ "hmac",
+ "http 1.4.2",
+ "reqwest 0.13.4",
+ "rustc_version",
+ "rustls 0.23.41",
+ "rustls-pki-types",
+ "serde",
+ "serde_json",
+ "sha2 0.11.0",
+ "thiserror 2.0.18",
+ "time",
+ "tokio",
+ "url",
+]
+
+[[package]]
+name = "google-cloud-gax"
+version = "1.12.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3103a4a9013f1aed573ca56e19a9680b0211643a99ea85caf524b397d6be8be3"
+dependencies = [
+ "bytes",
+ "futures",
+ "google-cloud-rpc",
+ "google-cloud-wkt",
+ "http 1.4.2",
+ "pin-project",
+ "rand 0.10.2",
+ "serde",
+ "serde_json",
+ "thiserror 2.0.18",
+ "tokio",
+]
+
+[[package]]
+name = "google-cloud-rpc"
+version = "1.6.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e2162c08a89118130979ba261080e960e44cdcb2d6e2ab8ca9b1da245285d353"
+dependencies = [
+ "bytes",
+ "google-cloud-wkt",
+ "serde",
+ "serde_json",
+ "serde_with",
+]
+
+[[package]]
+name = "google-cloud-wkt"
+version = "1.6.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "46df1fcc3ab69164af3f4199ed21f45b5dbc56d9f03211eb4fa20116d442364b"
+dependencies = [
+ "base64",
+ "bytes",
+ "serde",
+ "serde_json",
+ "serde_with",
+ "thiserror 2.0.18",
+ "time",
+ "url",
 ]
 
 [[package]]
@@ -830,7 +1027,7 @@ dependencies = [
  "futures-sink",
  "futures-util",
  "http 0.2.12",
- "indexmap",
+ "indexmap 2.14.0",
  "slab",
  "tokio",
  "tokio-util",
@@ -849,13 +1046,19 @@ dependencies = [
  "futures-core",
  "futures-sink",
  "http 1.4.2",
- "indexmap",
+ "indexmap 2.14.0",
  "slab",
  "tokio",
  "tokio-util",
  "tracing",
 ]
 
+[[package]]
+name = "hashbrown"
+version = "0.12.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8a9ee70c43aaf417c914396645a0fa852624801b24ebb7ae78fe8272889ac888"
+
 [[package]]
 name = "hashbrown"
 version = "0.17.1"
@@ -917,9 +1120,9 @@ dependencies = [
 
 [[package]]
 name = "http-body"
-version = "1.1.0"
+version = "1.0.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ca2a8f2913ee65f60facd6a5905613afaa448497a0230cc41ce022d93290bc2c"
+checksum = "1efedce1fb8e6913f23e0c92de8e62cd5b772a67e7b3946df930a62566c93184"
 dependencies = [
  "bytes",
  "http 1.4.2",
@@ -927,14 +1130,14 @@ dependencies = [
 
 [[package]]
 name = "http-body-util"
-version = "0.1.4"
+version = "0.1.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e9f41fd6a08e4d4ec69df65976da761afd5ad5e58a9d4acb46bd1c953a9e3ff2"
+checksum = "b021d93e26becf5dc7e1b75b1bed1fd93124b374ceb73f43d4d4eafec896a64a"
 dependencies = [
  "bytes",
  "futures-core",
  "http 1.4.2",
- "http-body 1.1.0",
+ "http-body 1.0.1",
  "pin-project-lite",
 ]
 
@@ -995,7 +1198,7 @@ dependencies = [
  "futures-core",
  "h2 0.4.15",
  "http 1.4.2",
- "http-body 1.1.0",
+ "http-body 1.0.1",
  "httparse",
  "httpdate",
  "itoa",
@@ -1029,7 +1232,7 @@ dependencies = [
  "http 1.4.2",
  "hyper 1.10.1",
  "hyper-util",
- "rustls 0.23.42",
+ "rustls 0.23.41",
  "rustls-native-certs",
  "tokio",
  "tokio-rustls 0.26.4",
@@ -1048,18 +1251,42 @@ dependencies = [
  "futures-channel",
  "futures-util",
  "http 1.4.2",
- "http-body 1.1.0",
+ "http-body 1.0.1",
  "hyper 1.10.1",
  "ipnet",
  "libc",
  "percent-encoding",
  "pin-project-lite",
- "socket2 0.6.5",
+ "socket2 0.6.4",
  "tokio",
  "tower-service",
  "tracing",
 ]
 
+[[package]]
+name = "iana-time-zone"
+version = "0.1.65"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e31bc9ad994ba00e440a8aa5c9ef0ec67d5cb5e5cb0cc7f8b744a35b389cc470"
+dependencies = [
+ "android_system_properties",
+ "core-foundation-sys",
+ "iana-time-zone-haiku",
+ "js-sys",
+ "log",
+ "wasm-bindgen",
+ "windows-core",
+]
+
+[[package]]
+name = "iana-time-zone-haiku"
+version = "0.1.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f31827a206f56af32e590ba56d5d2d085f558508192593743f16b2306495269f"
+dependencies = [
+ "cc",
+]
+
 [[package]]
 name = "icu_collections"
 version = "2.2.0"
@@ -1142,6 +1369,12 @@ dependencies = [
  "zerovec",
 ]
 
+[[package]]
+name = "ident_case"
+version = "1.0.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b9e0384b61958566e926dc50660321d12159025e767c18e043daf26b70104c39"
+
 [[package]]
 name = "idna"
 version = "1.1.0"
@@ -1163,6 +1396,17 @@ dependencies = [
  "icu_properties",
 ]
 
+[[package]]
+name = "indexmap"
+version = "1.9.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "bd070e393353796e801d209ad339e89596eb4c8d430d18ede6a1cced8fafbd99"
+dependencies = [
+ "autocfg",
+ "hashbrown 0.12.3",
+ "serde",
+]
+
 [[package]]
 name = "indexmap"
 version = "2.14.0"
@@ -1170,7 +1414,9 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d466e9454f08e4a911e14806c24e16fba1b4c121d1ea474396f396069cf949d9"
 dependencies = [
  "equivalent",
- "hashbrown",
+ "hashbrown 0.17.1",
+ "serde",
+ "serde_core",
 ]
 
 [[package]]
@@ -1185,6 +1431,55 @@ version = "1.0.18"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "8f42a60cbdf9a97f5d2305f08a87dc4e09308d1276d28c869c684d7777685682"
 
+[[package]]
+name = "jni"
+version = "0.22.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5efd9a482cf3a427f00d6b35f14332adc7902ce91efb778580e180ff90fa3498"
+dependencies = [
+ "cfg-if",
+ "combine",
+ "jni-macros",
+ "jni-sys",
+ "log",
+ "simd_cesu8",
+ "thiserror 2.0.18",
+ "walkdir",
+ "windows-link",
+]
+
+[[package]]
+name = "jni-macros"
+version = "0.22.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a00109accc170f0bdb141fed3e393c565b6f5e072365c3bd58f5b062591560a3"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "rustc_version",
+ "simd_cesu8",
+ "syn 2.0.118",
+]
+
+[[package]]
+name = "jni-sys"
+version = "0.4.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c6377a88cb3910bee9b0fa88d4f42e1d2da8e79915598f65fb0c7ee14c878af2"
+dependencies = [
+ "jni-sys-macros",
+]
+
+[[package]]
+name = "jni-sys-macros"
+version = "0.4.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "38c0b942f458fe50cdac086d2f946512305e5631e720728f2a61aabcd47a6264"
+dependencies = [
+ "quote",
+ "syn 2.0.118",
+]
+
 [[package]]
 name = "jobserver"
 version = "0.1.35"
@@ -1222,7 +1517,7 @@ dependencies = [
  "futures-util",
  "litellm-core",
  "pyo3",
- "reqwest",
+ "reqwest 0.12.28",
  "serde",
  "serde_json",
  "sha2 0.10.9",
@@ -1242,12 +1537,13 @@ dependencies = [
  "aws-sigv4",
  "aws-smithy-runtime-api",
  "aws-types",
- "rand 0.8.7",
- "reqwest",
+ "google-cloud-auth",
+ "rand 0.8.6",
+ "reqwest 0.12.28",
  "serde",
  "serde_json",
  "sha2 0.10.9",
- "thiserror 2.0.19",
+ "thiserror 2.0.18",
  "tokio",
 ]
 
@@ -1289,9 +1585,9 @@ checksum = "0e7465ac9959cc2b1404e8e2367b43684a6d13790fe23056cc8c6c5a6b7bcb94"
 
 [[package]]
 name = "memchr"
-version = "2.8.3"
+version = "2.8.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "cf8baf1c55e62ffcace7a9f06f4bd9cd3f0c4beb022d3b367256b91b87513d98"
+checksum = "88904434abc2901f197fe8cc55f0445e7ded921dba5911dad2e2b39b48e663c4"
 
 [[package]]
 name = "mime"
@@ -1301,9 +1597,9 @@ checksum = "6877bb514081ee2a7ff5ef9de3281f14a4dd4bceac4c09388074a6b5df8a139a"
 
 [[package]]
 name = "mio"
-version = "1.2.2"
+version = "1.2.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "30d65c71f1ce40ab09135ce117d742b9f8a19ff91a41a8b57ed50bc2de59c427"
+checksum = "02bd0af71c67b473010cbbc60715ee815645a4dc942899111f494b4b737d6fda"
 dependencies = [
  "libc",
  "wasi",
@@ -1358,6 +1654,26 @@ version = "2.3.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "9b4f627cb1b25917193a259e49bdad08f671f8d9708acfd5fe0a8c1455d87220"
 
+[[package]]
+name = "pin-project"
+version = "1.1.13"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2466b2336ed02bcdca6b294417127b90ec92038d1d5c4fbeac971a922e0e0924"
+dependencies = [
+ "pin-project-internal",
+]
+
+[[package]]
+name = "pin-project-internal"
+version = "1.1.13"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c96395f0a926bc13b1c17622aaddda1ecb55d49c8f1bf9777e4d877800a43f8b"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn 2.0.118",
+]
+
 [[package]]
 name = "pin-project-lite"
 version = "0.2.17"
@@ -1378,9 +1694,9 @@ checksum = "19f132c84eca552bf34cab8ec81f1c1dcc229b811638f9d283dceabe58c5569e"
 
 [[package]]
 name = "portable-atomic"
-version = "1.14.0"
+version = "1.13.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "3d20d5497ef88037a52ff98267d066e7f11fcc5e99bbfbd58a42336193aacec3"
+checksum = "c33a9471896f1c69cecef8d20cbe2f7accd12527ce60845ff44c153bb2a21b49"
 
 [[package]]
 name = "potential_utf"
@@ -1408,9 +1724,9 @@ dependencies = [
 
 [[package]]
 name = "proc-macro2"
-version = "1.0.107"
+version = "1.0.106"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "985e7ec9bb745e6ce6535b544d84d6cd6f7ad8bd711c398938ae983b91a766d9"
+checksum = "8fd00f0bb2e90d81d1044c2b32617f68fcb9fa3bb7640c23e9c748e53fb30934"
 dependencies = [
  "unicode-ident",
 ]
@@ -1471,7 +1787,7 @@ dependencies = [
  "proc-macro2",
  "pyo3-macros-backend",
  "quote",
- "syn 2.0.119",
+ "syn 2.0.118",
 ]
 
 [[package]]
@@ -1483,7 +1799,7 @@ dependencies = [
  "heck",
  "proc-macro2",
  "quote",
- "syn 2.0.119",
+ "syn 2.0.118",
 ]
 
 [[package]]
@@ -1498,9 +1814,9 @@ dependencies = [
  "quinn-proto",
  "quinn-udp",
  "rustc-hash",
- "rustls 0.23.42",
- "socket2 0.6.5",
- "thiserror 2.0.19",
+ "rustls 0.23.41",
+ "socket2 0.6.4",
+ "thiserror 2.0.18",
  "tokio",
  "tracing",
  "web-time",
@@ -1508,21 +1824,21 @@ dependencies = [
 
 [[package]]
 name = "quinn-proto"
-version = "0.11.16"
+version = "0.11.15"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2f4bfc015262b9df63c8845072ce59068853ff5872180c2ce2f13038b970e560"
+checksum = "4fcb935c5bec503c2f0e306bdd3e58bb9029dcb14fa8d9ac76e3a5256ac0763e"
 dependencies = [
+ "aws-lc-rs",
  "bytes",
- "getrandom 0.4.3",
+ "getrandom 0.3.4",
  "lru-slab",
- "rand 0.10.2",
- "rand_pcg",
+ "rand 0.9.4",
  "ring",
  "rustc-hash",
- "rustls 0.23.42",
+ "rustls 0.23.41",
  "rustls-pki-types",
  "slab",
- "thiserror 2.0.19",
+ "thiserror 2.0.18",
  "tinyvec",
  "tracing",
  "web-time",
@@ -1530,27 +1846,33 @@ dependencies = [
 
 [[package]]
 name = "quinn-udp"
-version = "0.5.15"
+version = "0.5.14"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "35a133f956daabe89a61a685c2649f13d82d5aa4bd5d12d1277e1072a21c0694"
+checksum = "addec6a0dcad8a8d96a771f815f0eaf55f9d1805756410b39f5fa81332574cbd"
 dependencies = [
  "cfg_aliases",
  "libc",
  "once_cell",
- "socket2 0.6.5",
+ "socket2 0.6.4",
  "tracing",
- "windows-sys 0.61.2",
+ "windows-sys 0.60.2",
 ]
 
 [[package]]
 name = "quote"
-version = "1.0.47"
+version = "1.0.46"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1fbf4db142a473a8d80c26bbf18454ed458bf8d26c8219c331daecfdbd079001"
+checksum = "dfbc457d0c7a0759a614551b11a6409e5951f6c7537be1f1b7682b9ae9230368"
 dependencies = [
  "proc-macro2",
 ]
 
+[[package]]
+name = "r-efi"
+version = "5.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "69cdb34c158ceb288df11e18b4bd39de994f6657d83847bdffdbd7f346754b0f"
+
 [[package]]
 name = "r-efi"
 version = "6.0.0"
@@ -1559,15 +1881,25 @@ checksum = "f8dcc9c7d52a811697d2151c701e0d08956f92b0e24136cf4cf27b57a6a0d9bf"
 
 [[package]]
 name = "rand"
-version = "0.8.7"
+version = "0.8.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "22f6172bdec972074665ed81ed53b71da00bfc44b65a753cfde883ec4c702a1a"
+checksum = "5ca0ecfa931c29007047d1bc58e623ab12e5590e8c7cc53200d5202b69266d8a"
 dependencies = [
  "libc",
- "rand_chacha",
+ "rand_chacha 0.3.1",
  "rand_core 0.6.4",
 ]
 
+[[package]]
+name = "rand"
+version = "0.9.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "44c5af06bb1b7d3216d91932aed5265164bf384dc89cd6ba05cf59a35f5f76ea"
+dependencies = [
+ "rand_chacha 0.9.0",
+ "rand_core 0.9.5",
+]
+
 [[package]]
 name = "rand"
 version = "0.10.2"
@@ -1589,6 +1921,16 @@ dependencies = [
  "rand_core 0.6.4",
 ]
 
+[[package]]
+name = "rand_chacha"
+version = "0.9.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d3022b5f1df60f26e1ffddd6c66e8aa15de382ae63b3a0c1bfc0e4d3e3f325cb"
+dependencies = [
+ "ppv-lite86",
+ "rand_core 0.9.5",
+]
+
 [[package]]
 name = "rand_core"
 version = "0.6.4"
@@ -1598,6 +1940,15 @@ dependencies = [
  "getrandom 0.2.17",
 ]
 
+[[package]]
+name = "rand_core"
+version = "0.9.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "76afc826de14238e6e8c374ddcc1fa19e374fd8dd986b0d2af0d02377261d83c"
+dependencies = [
+ "getrandom 0.3.4",
+]
+
 [[package]]
 name = "rand_core"
 version = "0.10.1"
@@ -1605,12 +1956,23 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "63b8176103e19a2643978565ca18b50549f6101881c443590420e4dc998a3c69"
 
 [[package]]
-name = "rand_pcg"
-version = "0.10.2"
+name = "ref-cast"
+version = "1.0.26"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "caa0f4137e1c0a72f4c651489402276c8e8e1cf081f3b0ba156d2cbeef09e86a"
+checksum = "216e8f773d7923bcba9ceb86a86c93cabb3903a11872fc3f138c49630e50b96d"
 dependencies = [
- "rand_core 0.10.1",
+ "ref-cast-impl",
+]
+
+[[package]]
+name = "ref-cast-impl"
+version = "1.0.26"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2c9283685feec7d69af75fb0e858d5e7378f33fe4fc699383b2916ab9273e03c"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn 3.0.0",
 ]
 
 [[package]]
@@ -1632,7 +1994,7 @@ dependencies = [
  "futures-util",
  "h2 0.4.15",
  "http 1.4.2",
- "http-body 1.1.0",
+ "http-body 1.0.1",
  "http-body-util",
  "hyper 1.10.1",
  "hyper-rustls 0.27.9",
@@ -1642,7 +2004,7 @@ dependencies = [
  "percent-encoding",
  "pin-project-lite",
  "quinn",
- "rustls 0.23.42",
+ "rustls 0.23.41",
  "rustls-pki-types",
  "serde",
  "serde_json",
@@ -1662,6 +2024,44 @@ dependencies = [
  "webpki-roots",
 ]
 
+[[package]]
+name = "reqwest"
+version = "0.13.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "219c5811de6525e5416c7d5d53bb656d3afdbc6c5af816e0802bcfa42dbdc1c3"
+dependencies = [
+ "base64",
+ "bytes",
+ "futures-core",
+ "http 1.4.2",
+ "http-body 1.0.1",
+ "http-body-util",
+ "hyper 1.10.1",
+ "hyper-rustls 0.27.9",
+ "hyper-util",
+ "js-sys",
+ "log",
+ "percent-encoding",
+ "pin-project-lite",
+ "quinn",
+ "rustls 0.23.41",
+ "rustls-pki-types",
+ "rustls-platform-verifier",
+ "serde",
+ "serde_json",
+ "serde_urlencoded",
+ "sync_wrapper",
+ "tokio",
+ "tokio-rustls 0.26.4",
+ "tower",
+ "tower-http",
+ "tower-service",
+ "url",
+ "wasm-bindgen",
+ "wasm-bindgen-futures",
+ "web-sys",
+]
+
 [[package]]
 name = "ring"
 version = "0.17.14"
@@ -1678,9 +2078,9 @@ dependencies = [
 
 [[package]]
 name = "rustc-hash"
-version = "2.1.3"
+version = "2.1.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "6b1e7f9a428571be2dc5bc0505c13fb6bf936822b894ec87abf8a08a4e51742d"
+checksum = "94300abf3f1ae2e2b8ffb7b58043de3d399c73fa6f4b73826402a5c457614dbe"
 
 [[package]]
 name = "rustc_version"
@@ -1705,11 +2105,12 @@ dependencies = [
 
 [[package]]
 name = "rustls"
-version = "0.23.42"
+version = "0.23.41"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "3c54fcab019b409d04215d3a17cb438fd7fbf192ee61461f20f4fe18704bc138"
+checksum = "6b92b125634d9b795e7beca796cc790df15a7fb38323bf3196fda83292d06b1f"
 dependencies = [
  "aws-lc-rs",
+ "log",
  "once_cell",
  "ring",
  "rustls-pki-types",
@@ -1732,14 +2133,41 @@ dependencies = [
 
 [[package]]
 name = "rustls-pki-types"
-version = "1.15.0"
+version = "1.14.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "764899a24af3980067ee14bc143654f297b22eaebfe3c7b6b211920a5a59b046"
+checksum = "30a7197ae7eb376e574fe940d068c30fe0462554a3ddbe4eca7838e049c937a9"
 dependencies = [
  "web-time",
  "zeroize",
 ]
 
+[[package]]
+name = "rustls-platform-verifier"
+version = "0.7.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "26d1e2536ce4f35f4846aa13bff16bd0ff40157cdb14cc056c7b14ba41233ba0"
+dependencies = [
+ "core-foundation",
+ "core-foundation-sys",
+ "jni",
+ "log",
+ "once_cell",
+ "rustls 0.23.41",
+ "rustls-native-certs",
+ "rustls-platform-verifier-android",
+ "rustls-webpki 0.103.13",
+ "security-framework",
+ "security-framework-sys",
+ "webpki-root-certs",
+ "windows-sys 0.61.2",
+]
+
+[[package]]
+name = "rustls-platform-verifier-android"
+version = "0.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f87165f0995f63a9fbeea62b64d10b4d9d8e78ec6d7d51fb2125fda7bb36788f"
+
 [[package]]
 name = "rustls-webpki"
 version = "0.101.7"
@@ -1764,9 +2192,9 @@ dependencies = [
 
 [[package]]
 name = "rustversion"
-version = "1.0.23"
+version = "1.0.22"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "cf54715a573b99ac80df0bc206da022bcd442c974952c7b9720069370852e21f"
+checksum = "b39cdef0fa800fc44525c84ccb54a029961a8215f9619753635a9c0d2538d46d"
 
 [[package]]
 name = "ryu"
@@ -1774,6 +2202,15 @@ version = "1.0.23"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "9774ba4a74de5f7b1c1451ed6cd5285a32eddb5cccb8cc655a4e50009e06477f"
 
+[[package]]
+name = "same-file"
+version = "1.0.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "93fc1dc3aaa9bfed95e02e6eadabb4baf7e3078b0bd1b4d7b6b0b68378900502"
+dependencies = [
+ "winapi-util",
+]
+
 [[package]]
 name = "schannel"
 version = "0.1.29"
@@ -1783,6 +2220,30 @@ dependencies = [
  "windows-sys 0.61.2",
 ]
 
+[[package]]
+name = "schemars"
+version = "0.9.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "4cd191f9397d57d581cddd31014772520aa448f65ef991055d7f61582c65165f"
+dependencies = [
+ "dyn-clone",
+ "ref-cast",
+ "serde",
+ "serde_json",
+]
+
+[[package]]
+name = "schemars"
+version = "1.2.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a2b42f36aa1cd011945615b92222f6bf73c599a102a300334cd7f8dbeec726cc"
+dependencies = [
+ "dyn-clone",
+ "ref-cast",
+ "serde",
+ "serde_json",
+]
+
 [[package]]
 name = "sct"
 version = "0.7.1"
@@ -1824,9 +2285,9 @@ checksum = "8a7852d02fc848982e0c167ef163aaff9cd91dc640ba85e263cb1ce46fae51cd"
 
 [[package]]
 name = "serde"
-version = "1.0.229"
+version = "1.0.228"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4148590afebada386688f18773da617792bf2ef03ffc1e4cbd2b1d45b023e0ba"
+checksum = "9a8e94ea7f378bd32cbbd37198a4a91436180c5bb472411e48b5ec2e2124ae9e"
 dependencies = [
  "serde_core",
  "serde_derive",
@@ -1834,22 +2295,22 @@ dependencies = [
 
 [[package]]
 name = "serde_core"
-version = "1.0.229"
+version = "1.0.228"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "67dca2c9c51e58a4791a4b1ed58308b39c64224d349a935ab5039aa360942a48"
+checksum = "41d385c7d4ca58e59fc732af25c3983b67ac852c1a25000afe1175de458b67ad"
 dependencies = [
  "serde_derive",
 ]
 
 [[package]]
 name = "serde_derive"
-version = "1.0.229"
+version = "1.0.228"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e7a5d71263a5a7d47b41f6b3f06ba276f10cc18b0931f1799f710578e2309348"
+checksum = "d540f220d3187173da220f885ab66608367b6574e925011a9353e4badda91d79"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 3.0.0",
+ "syn 2.0.118",
 ]
 
 [[package]]
@@ -1889,10 +2350,42 @@ dependencies = [
 ]
 
 [[package]]
-name = "sha1"
-version = "0.10.7"
+name = "serde_with"
+version = "3.21.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a978451301f4db1d02937a4ab3ccce137717b81826e79b7d49ffe3244a13c3b8"
+checksum = "76a5c54c7310e7b8b9577c286d7e399ddd876c3e12b3ed917a8aabc4b96e9e8c"
+dependencies = [
+ "base64",
+ "bs58",
+ "chrono",
+ "hex",
+ "indexmap 1.9.3",
+ "indexmap 2.14.0",
+ "schemars 0.9.0",
+ "schemars 1.2.1",
+ "serde_core",
+ "serde_json",
+ "serde_with_macros",
+ "time",
+]
+
+[[package]]
+name = "serde_with_macros"
+version = "3.21.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "84d57bc0c8b9a17920c178daa6bb924850d54a9c97ab45194bb8c17ad66bb660"
+dependencies = [
+ "darling",
+ "proc-macro2",
+ "quote",
+ "syn 2.0.118",
+]
+
+[[package]]
+name = "sha1"
+version = "0.10.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e3bf829a2d51ab4a5ddf1352d8470c140cadc8301b2ae1789db023f01cedd6ba"
 dependencies = [
  "cfg-if",
  "cpufeatures 0.2.17",
@@ -1927,6 +2420,32 @@ version = "2.0.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "f8fadd59c855ef2080decdef8ff161eb6661b86933c9d82e5ba29dc602a55aba"
 
+[[package]]
+name = "signal-hook-registry"
+version = "1.4.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c4db69cba1110affc0e9f7bcd48bbf87b3f4fc7c61fc9155afd4c469eb3d6c1b"
+dependencies = [
+ "errno",
+ "libc",
+]
+
+[[package]]
+name = "simd_cesu8"
+version = "1.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "11031e251abf8611c80f460e19dbdeb54a66db918e49c65a7065b46ac7aec520"
+dependencies = [
+ "rustc_version",
+ "simdutf8",
+]
+
+[[package]]
+name = "simdutf8"
+version = "0.1.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e3a9fe34e3e7a50316060351f37187a3f546bce95496156754b601a5fa71b76e"
+
 [[package]]
 name = "slab"
 version = "0.4.12"
@@ -1951,9 +2470,9 @@ dependencies = [
 
 [[package]]
 name = "socket2"
-version = "0.6.5"
+version = "0.6.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c3d1e2c7f27f8d4cb10542a02c49005dbd6e93095799d6f3be745fae9f8fedd4"
+checksum = "52d1cfed4120b4d927bf7c0f86d2087a4a7d6027c906d9f9d525a80573b9be51"
 dependencies = [
  "libc",
  "windows-sys 0.61.2",
@@ -1965,6 +2484,12 @@ version = "1.2.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "6ce2be8dc25455e1f91df71bfa12ad37d7af1092ae736f3a6cd0e37bc7810596"
 
+[[package]]
+name = "strsim"
+version = "0.11.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7da8b5736845d9f2fcb837ea5d9e2628564b3b043a70948a3f0b778838c5fb4f"
+
 [[package]]
 name = "subtle"
 version = "2.6.1"
@@ -1973,9 +2498,9 @@ checksum = "13c2bddecc57b384dee18652358fb23172facb8a2c51ccc10d74c157bdea3292"
 
 [[package]]
 name = "syn"
-version = "2.0.119"
+version = "2.0.118"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "872831b642d1a07999a962a351ed35b955ea2cfc8f3862091e2a240a84f17297"
+checksum = "1b9ae57f904213ebb649ce6895b8a66c66f0203b9319718f69a5612a065b1422"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -2010,7 +2535,7 @@ checksum = "728a70f3dbaf5bab7f0c4b1ac8d7ae5ea60a4b5549c8a5914361c99147a709d2"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.119",
+ "syn 2.0.118",
 ]
 
 [[package]]
@@ -2030,11 +2555,11 @@ dependencies = [
 
 [[package]]
 name = "thiserror"
-version = "2.0.19"
+version = "2.0.18"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "09a43598840e33d5b0331f38c5e30d13bb11c11210a4b58f0d9b18a5a5eefcd9"
+checksum = "4288b5bcbc7920c07a1149a35cf9590a2aa808e0bc1eafaade0b80947865fbc4"
 dependencies = [
- "thiserror-impl 2.0.19",
+ "thiserror-impl 2.0.18",
 ]
 
 [[package]]
@@ -2045,18 +2570,18 @@ checksum = "4fee6c4efc90059e10f81e6d42c60a18f76588c3d74cb83a0b242a2b6c7504c1"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.119",
+ "syn 2.0.118",
 ]
 
 [[package]]
 name = "thiserror-impl"
-version = "2.0.19"
+version = "2.0.18"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "43cbfe0cf76104d42a574802844187e84a305e531ed54455f11fbde0f10541cd"
+checksum = "ebc4ee7f67670e9b64d05fa4253e753e016c6c95ff35b89b7941d6b856dec1d5"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 3.0.0",
+ "syn 2.0.118",
 ]
 
 [[package]]
@@ -2101,9 +2626,9 @@ dependencies = [
 
 [[package]]
 name = "tinyvec"
-version = "1.12.0"
+version = "1.11.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "bb4ebadaa0af04fab11ae01eb5f9fdb5f9c5b875506e210e71c07873528baa7f"
+checksum = "3e61e67053d25a4e82c844e8424039d9745781b3fc4f32b8d55ed50f5f667ef3"
 dependencies = [
  "tinyvec_macros",
 ]
@@ -2116,28 +2641,29 @@ checksum = "1f3ccbac311fea05f86f61904b462b55fb3df8837a366dfc601a0161d0532f20"
 
 [[package]]
 name = "tokio"
-version = "1.53.0"
+version = "1.52.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d988bcd52dbe076d3d46903332f58c912b87a2c49b1428419a5845154762ffee"
+checksum = "8fc7f01b389ac15039e4dc9531aa973a135d7a4135281b12d7c1bc79fd57fffe"
 dependencies = [
  "bytes",
  "libc",
  "mio",
  "pin-project-lite",
- "socket2 0.6.5",
+ "signal-hook-registry",
+ "socket2 0.6.4",
  "tokio-macros",
  "windows-sys 0.61.2",
 ]
 
 [[package]]
 name = "tokio-macros"
-version = "2.7.1"
+version = "2.7.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "6328af13490e73a9b4694030fafd93f8c8c6a9dede33e821c3fc63eddf8042ba"
+checksum = "385a6cb71ab9ab790c5fe8d67f1645e6c450a7ce006a33de03daa956cf70a496"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.119",
+ "syn 2.0.118",
 ]
 
 [[package]]
@@ -2156,7 +2682,7 @@ version = "0.26.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "1729aa945f29d91ba541258c8df89027d5792d85a8841fb65e8bf0f4ede4ef61"
 dependencies = [
- "rustls 0.23.42",
+ "rustls 0.23.41",
  "tokio",
 ]
 
@@ -2168,7 +2694,7 @@ checksum = "edc5f74e248dc973e0dbb7b74c7e0d6fcc301c694ff50049504004ef4d0cdcd9"
 dependencies = [
  "futures-util",
  "log",
- "rustls 0.23.42",
+ "rustls 0.23.41",
  "rustls-native-certs",
  "rustls-pki-types",
  "tokio",
@@ -2215,7 +2741,7 @@ dependencies = [
  "bytes",
  "futures-util",
  "http 1.4.2",
- "http-body 1.1.0",
+ "http-body 1.0.1",
  "pin-project-lite",
  "tower",
  "tower-layer",
@@ -2255,7 +2781,7 @@ checksum = "7490cfa5ec963746568740651ac6781f701c9c5ea257c58e057f3ba8cf69e8da"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.119",
+ "syn 2.0.118",
 ]
 
 [[package]]
@@ -2285,8 +2811,8 @@ dependencies = [
  "http 1.4.2",
  "httparse",
  "log",
- "rand 0.8.7",
- "rustls 0.23.42",
+ "rand 0.8.6",
+ "rustls 0.23.41",
  "rustls-pki-types",
  "sha1",
  "thiserror 1.0.69",
@@ -2363,6 +2889,16 @@ version = "0.8.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "5c3082ca00d5a5ef149bb8b555a72ae84c9c59f7250f013ac822ac2e49b19c64"
 
+[[package]]
+name = "walkdir"
+version = "2.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "29790946404f91d9c5d06f9874efddea1dc06c5efe94541a7d6863108e3a5e4b"
+dependencies = [
+ "same-file",
+ "winapi-util",
+]
+
 [[package]]
 name = "want"
 version = "0.3.1"
@@ -2378,6 +2914,15 @@ version = "0.11.1+wasi-snapshot-preview1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ccf3ec651a847eb01de73ccad15eb7d99f80485de043efb2f370cd654f4ea44b"
 
+[[package]]
+name = "wasip2"
+version = "1.0.4+wasi-0.2.12"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b67efb37e106e55ce722a510d6b5f9c17f083e5fc79afc2badeb12cc313d9487"
+dependencies = [
+ "wit-bindgen",
+]
+
 [[package]]
 name = "wasm-bindgen"
 version = "0.2.126"
@@ -2420,7 +2965,7 @@ dependencies = [
  "bumpalo",
  "proc-macro2",
  "quote",
- "syn 2.0.119",
+ "syn 2.0.118",
  "wasm-bindgen-shared",
 ]
 
@@ -2467,27 +3012,107 @@ dependencies = [
 ]
 
 [[package]]
-name = "webpki-roots"
+name = "webpki-root-certs"
 version = "1.0.9"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7dcd9d09a39985f5344844e66b0c530a33843579125f23e21e9f0f220850f22a"
+checksum = "b96554aa2acc8ccdb7e1c9a58a7a68dd5d13bccc69cd124cb09406db612a1c9b"
 dependencies = [
  "rustls-pki-types",
 ]
 
+[[package]]
+name = "webpki-roots"
+version = "1.0.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "bf85cb06032201fa7c6f829d7db5a7e5aa45bcc0655327713065f6f0576731bf"
+dependencies = [
+ "rustls-pki-types",
+]
+
+[[package]]
+name = "winapi-util"
+version = "0.1.11"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c2a7b1c03c876122aa43f3020e6c3c3ee5c05081c9a00739faf7503aeba10d22"
+dependencies = [
+ "windows-sys 0.61.2",
+]
+
+[[package]]
+name = "windows-core"
+version = "0.62.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b8e83a14d34d0623b51dce9581199302a221863196a1dde71a7663a4c2be9deb"
+dependencies = [
+ "windows-implement",
+ "windows-interface",
+ "windows-link",
+ "windows-result",
+ "windows-strings",
+]
+
+[[package]]
+name = "windows-implement"
+version = "0.60.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "053e2e040ab57b9dc951b72c264860db7eb3b0200ba345b4e4c3b14f67855ddf"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn 2.0.118",
+]
+
+[[package]]
+name = "windows-interface"
+version = "0.59.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3f316c4a2570ba26bbec722032c4099d8c8bc095efccdc15688708623367e358"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn 2.0.118",
+]
+
 [[package]]
 name = "windows-link"
 version = "0.2.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "f0805222e57f7521d6a62e36fa9163bc891acd422f971defe97d64e70d0a4fe5"
 
+[[package]]
+name = "windows-result"
+version = "0.4.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7781fa89eaf60850ac3d2da7af8e5242a5ea78d1a11c49bf2910bb5a73853eb5"
+dependencies = [
+ "windows-link",
+]
+
+[[package]]
+name = "windows-strings"
+version = "0.5.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7837d08f69c77cf6b07689544538e017c1bfcf57e34b4c0ff58e6c2cd3b37091"
+dependencies = [
+ "windows-link",
+]
+
 [[package]]
 name = "windows-sys"
 version = "0.52.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "282be5f36a8ce781fad8c8ae18fa3f9beff57ec1b52cb3de0789201425d9a33d"
 dependencies = [
- "windows-targets",
+ "windows-targets 0.52.6",
+]
+
+[[package]]
+name = "windows-sys"
+version = "0.60.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f2f500e4d28234f72040990ec9d39e3a6b950f9f22d3dba18416c35882612bcb"
+dependencies = [
+ "windows-targets 0.53.5",
 ]
 
 [[package]]
@@ -2505,14 +3130,31 @@ version = "0.52.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "9b724f72796e036ab90c1021d4780d4d3d648aca59e491e6b98e725b84e99973"
 dependencies = [
- "windows_aarch64_gnullvm",
- "windows_aarch64_msvc",
- "windows_i686_gnu",
- "windows_i686_gnullvm",
- "windows_i686_msvc",
- "windows_x86_64_gnu",
- "windows_x86_64_gnullvm",
- "windows_x86_64_msvc",
+ "windows_aarch64_gnullvm 0.52.6",
+ "windows_aarch64_msvc 0.52.6",
+ "windows_i686_gnu 0.52.6",
+ "windows_i686_gnullvm 0.52.6",
+ "windows_i686_msvc 0.52.6",
+ "windows_x86_64_gnu 0.52.6",
+ "windows_x86_64_gnullvm 0.52.6",
+ "windows_x86_64_msvc 0.52.6",
+]
+
+[[package]]
+name = "windows-targets"
+version = "0.53.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "4945f9f551b88e0d65f3db0bc25c33b8acea4d9e41163edf90dcd0b19f9069f3"
+dependencies = [
+ "windows-link",
+ "windows_aarch64_gnullvm 0.53.1",
+ "windows_aarch64_msvc 0.53.1",
+ "windows_i686_gnu 0.53.1",
+ "windows_i686_gnullvm 0.53.1",
+ "windows_i686_msvc 0.53.1",
+ "windows_x86_64_gnu 0.53.1",
+ "windows_x86_64_gnullvm 0.53.1",
+ "windows_x86_64_msvc 0.53.1",
 ]
 
 [[package]]
@@ -2521,48 +3163,102 @@ version = "0.52.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "32a4622180e7a0ec044bb555404c800bc9fd9ec262ec147edd5989ccd0c02cd3"
 
+[[package]]
+name = "windows_aarch64_gnullvm"
+version = "0.53.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a9d8416fa8b42f5c947f8482c43e7d89e73a173cead56d044f6a56104a6d1b53"
+
 [[package]]
 name = "windows_aarch64_msvc"
 version = "0.52.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "09ec2a7bb152e2252b53fa7803150007879548bc709c039df7627cabbd05d469"
 
+[[package]]
+name = "windows_aarch64_msvc"
+version = "0.53.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b9d782e804c2f632e395708e99a94275910eb9100b2114651e04744e9b125006"
+
 [[package]]
 name = "windows_i686_gnu"
 version = "0.52.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "8e9b5ad5ab802e97eb8e295ac6720e509ee4c243f69d781394014ebfe8bbfa0b"
 
+[[package]]
+name = "windows_i686_gnu"
+version = "0.53.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "960e6da069d81e09becb0ca57a65220ddff016ff2d6af6a223cf372a506593a3"
+
 [[package]]
 name = "windows_i686_gnullvm"
 version = "0.52.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "0eee52d38c090b3caa76c563b86c3a4bd71ef1a819287c19d586d7334ae8ed66"
 
+[[package]]
+name = "windows_i686_gnullvm"
+version = "0.53.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "fa7359d10048f68ab8b09fa71c3daccfb0e9b559aed648a8f95469c27057180c"
+
 [[package]]
 name = "windows_i686_msvc"
 version = "0.52.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "240948bc05c5e7c6dabba28bf89d89ffce3e303022809e73deaefe4f6ec56c66"
 
+[[package]]
+name = "windows_i686_msvc"
+version = "0.53.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1e7ac75179f18232fe9c285163565a57ef8d3c89254a30685b57d83a38d326c2"
+
 [[package]]
 name = "windows_x86_64_gnu"
 version = "0.52.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "147a5c80aabfbf0c7d901cb5895d1de30ef2907eb21fbbab29ca94c5b08b1a78"
 
+[[package]]
+name = "windows_x86_64_gnu"
+version = "0.53.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9c3842cdd74a865a8066ab39c8a7a473c0778a3f29370b5fd6b4b9aa7df4a499"
+
 [[package]]
 name = "windows_x86_64_gnullvm"
 version = "0.52.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "24d5b23dc417412679681396f2b49f3de8c1473deb516bd34410872eff51ed0d"
 
+[[package]]
+name = "windows_x86_64_gnullvm"
+version = "0.53.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0ffa179e2d07eee8ad8f57493436566c7cc30ac536a3379fdf008f47f6bb7ae1"
+
 [[package]]
 name = "windows_x86_64_msvc"
 version = "0.52.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "589f6da84c646204747d1270a2a5661ea66ed1cced2631d546fdfb155959f9ec"
 
+[[package]]
+name = "windows_x86_64_msvc"
+version = "0.53.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d6bbff5f0aada427a1e5a6da5f1f98158182f26556f345ac9e04d36d0ebed650"
+
+[[package]]
+name = "wit-bindgen"
+version = "0.57.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1ebf944e87a7c253233ad6766e082e3cd714b5d03812acc24c318f549614536e"
+
 [[package]]
 name = "writeable"
 version = "0.6.3"
@@ -2594,28 +3290,28 @@ checksum = "de844c262c8848816172cef550288e7dc6c7b7814b4ee56b3e1553f275f1858e"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.119",
+ "syn 2.0.118",
  "synstructure",
 ]
 
 [[package]]
 name = "zerocopy"
-version = "0.8.54"
+version = "0.8.52"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b7cbbc0a705a0fd05cc3676525980d2bf5a9bc4adac6d6475209a7887cf59d19"
+checksum = "ce1022995ff5ff5d841ad7d994facc23098cd40152f2c1d11cd607c6f530653f"
 dependencies = [
  "zerocopy-derive",
 ]
 
 [[package]]
 name = "zerocopy-derive"
-version = "0.8.54"
+version = "0.8.52"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e2e817b7b52d0c7358d3246da9d69935ebb18116b2b102b4230dac079b4862f5"
+checksum = "1ae7f38b72ec2a254e2b87ef277cf2cd4fb97cbebf944faa6f33354da0867930"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.119",
+ "syn 2.0.118",
 ]
 
 [[package]]
@@ -2635,7 +3331,7 @@ checksum = "11532158c46691caf0f2593ea8358fed6bbf68a0315e80aae9bd41fbade684a1"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.119",
+ "syn 2.0.118",
  "synstructure",
 ]
 
@@ -2675,11 +3371,11 @@ checksum = "625dc425cab0dca6dc3c3319506e6593dcb08a9f387ea3b284dbd52a92c40555"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.119",
+ "syn 2.0.118",
 ]
 
 [[package]]
 name = "zmij"
-version = "1.0.23"
+version = "1.0.21"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "29666d0abbfad1e3dc4dcf6144730dd3a3ab225bbbdac83319345b1b44ccfc1b"
+checksum = "b8848ee67ecc8aedbaf3e4122217aff892639231befc6a1b58d29fff4c2cabaa"
diff --git a/litellm-rust/crates/core/Cargo.toml b/litellm-rust/crates/core/Cargo.toml
index ab8050734f2..59ecfc81835 100644
--- a/litellm-rust/crates/core/Cargo.toml
+++ b/litellm-rust/crates/core/Cargo.toml
@@ -18,6 +18,7 @@ aws-sdk-sts = { version = "1.108.0", default-features = false, features = ["rust
 aws-sigv4 = { version = "1.5.1", optional = true }
 aws-types = { version = "1.4.0", optional = true }
 aws-smithy-runtime-api = { version = "1.13.0", optional = true }
+google-cloud-auth = { version = "=1.12.0", default-features = false, features = ["default-rustls-provider"], optional = true }
 
 [features]
 default = []
@@ -29,6 +30,7 @@ bedrock-auth = [
     "dep:aws-types",
     "dep:aws-smithy-runtime-api",
 ]
+vertex-auth = ["dep:google-cloud-auth"]
 
 [dev-dependencies]
 tokio = { workspace = true, features = ["macros", "rt-multi-thread"] }
diff --git a/litellm-rust/crates/core/src/providers/vertex_ai/constants.rs b/litellm-rust/crates/core/src/providers/vertex_ai/constants.rs
new file mode 100644
index 00000000000..846d54213f8
--- /dev/null
+++ b/litellm-rust/crates/core/src/providers/vertex_ai/constants.rs
@@ -0,0 +1,7 @@
+pub const VERTEXAI_PROJECT: &str = "VERTEXAI_PROJECT";
+pub const VERTEXAI_LOCATION: &str = "VERTEXAI_LOCATION";
+pub const VERTEXAI_CREDENTIALS: &str = "VERTEXAI_CREDENTIALS";
+pub const GOOGLE_APPLICATION_CREDENTIALS: &str = "GOOGLE_APPLICATION_CREDENTIALS";
+pub const GOOGLE_CLOUD_PROJECT: &str = "GOOGLE_CLOUD_PROJECT";
+pub const GOOGLE_CLOUD_QUOTA_PROJECT: &str = "GOOGLE_CLOUD_QUOTA_PROJECT";
+pub const CLOUD_PLATFORM_SCOPE: &str = "https://www.googleapis.com/auth/cloud-platform";
diff --git a/litellm-rust/crates/core/src/providers/vertex_ai/mod.rs b/litellm-rust/crates/core/src/providers/vertex_ai/mod.rs
index 3621ff6a2fd..424eaab91cd 100644
--- a/litellm-rust/crates/core/src/providers/vertex_ai/mod.rs
+++ b/litellm-rust/crates/core/src/providers/vertex_ai/mod.rs
@@ -1 +1,5 @@
+#[cfg(feature = "vertex-auth")]
+mod constants;
 pub mod ocr;
+#[cfg(feature = "vertex-auth")]
+pub mod vertex_base;
diff --git a/litellm-rust/crates/core/src/providers/vertex_ai/vertex_base.rs b/litellm-rust/crates/core/src/providers/vertex_ai/vertex_base.rs
new file mode 100644
index 00000000000..df99dcf373d
--- /dev/null
+++ b/litellm-rust/crates/core/src/providers/vertex_ai/vertex_base.rs
@@ -0,0 +1,368 @@
+//! User-directed exception: this base provider owns Google auth I/O for parity
+//! with Python's `VertexBase`; the broader core purity guidance is reconciled
+//! separately.
+
+use std::env;
+use std::fs;
+use std::path::Path;
+use std::sync::{Mutex, OnceLock};
+
+use google_cloud_auth::credentials::AccessTokenCredentials;
+use google_cloud_auth::credentials::external_account;
+use google_cloud_auth::credentials::service_account;
+use google_cloud_auth::credentials::user_account;
+use serde_json::Value;
+use sha2::{Digest, Sha256};
+
+use crate::caching::in_memory_cache::InMemoryCache;
+use crate::error::{CoreError, CoreResult};
+
+use super::constants::{
+    CLOUD_PLATFORM_SCOPE, GOOGLE_APPLICATION_CREDENTIALS, GOOGLE_CLOUD_PROJECT,
+    GOOGLE_CLOUD_QUOTA_PROJECT, VERTEXAI_CREDENTIALS, VERTEXAI_LOCATION, VERTEXAI_PROJECT,
+};
+
+static VERTEX_CREDENTIALS_CACHE: OnceLock<Mutex<InMemoryCache<AccessTokenCredentials>>> =
+    OnceLock::new();
+
+// google-cloud-auth owns async token caching and refresh; Python's single-flight machinery is intentionally not ported.
+
+#[derive(Clone, Debug, PartialEq)]
+pub enum VertexCredentialsInput {
+    Json(Value),
+    String(String),
+}
+
+#[derive(Clone, Debug, Default, PartialEq)]
+pub struct VertexAuthConfig {
+    pub credentials: Option<VertexCredentialsInput>,
+    pub location: Option<String>,
+    pub project_id: Option<String>,
+}
+
+#[derive(Clone, Debug, PartialEq, Eq)]
+pub enum VertexAuthSource {
+    AwsWorkloadIdentity,
+    ExecutableWorkloadIdentity,
+    IdentityPoolWorkloadIdentity,
+    AuthorizedUser,
+    ServiceAccount,
+    DefaultAdc,
+}
+
+#[derive(Clone, Debug, PartialEq, Eq)]
+pub struct VertexToken {
+    pub access_token: String,
+    pub project_id: String,
+}
+
+impl VertexAuthConfig {
+    pub fn from_environment() -> Self {
+        Self {
+            credentials: non_empty_env(VERTEXAI_CREDENTIALS)
+                .or_else(|| non_empty_env(GOOGLE_APPLICATION_CREDENTIALS))
+                .map(VertexCredentialsInput::String),
+            location: non_empty_env(VERTEXAI_LOCATION),
+            project_id: non_empty_env(VERTEXAI_PROJECT)
+                .or_else(|| non_empty_env(GOOGLE_CLOUD_PROJECT)),
+        }
+    }
+}
+
+pub fn resolve_credentials_input(
+    credentials: Option<VertexCredentialsInput>,
+) -> CoreResult<Option<Value>> {
+    let Some(credentials) = credentials else {
+        return Ok(None);
+    };
+
+    let value = match credentials {
+        VertexCredentialsInput::Json(value) => value,
+        VertexCredentialsInput::String(value) => {
+            if value.trim().is_empty() {
+                return Ok(None);
+            }
+            let path = Path::new(&value);
+            let json = if path.is_file() {
+                fs::read_to_string(path).map_err(|error| {
+                    CoreError::Auth(format!("unable to read Vertex credentials file: {error}"))
+                })?
+            } else {
+                value
+            };
+            serde_json::from_str(&json).map_err(|error| {
+                CoreError::Auth(format!("invalid Vertex credentials JSON: {error}"))
+            })?
+        }
+    };
+
+    if value.is_object() {
+        Ok(Some(value))
+    } else {
+        Err(CoreError::InvalidType {
+            expected: "object",
+            actual: crate::error::json_type_name(&value),
+        })
+    }
+}
+
+pub fn classify_auth(credentials: Option<&Value>) -> VertexAuthSource {
+    let Some(credentials) = credentials else {
+        return VertexAuthSource::DefaultAdc;
+    };
+
+    let credential_type = credentials.get("type").and_then(Value::as_str);
+    if credential_type == Some("external_account") {
+        let source = credentials
+            .get("credential_source")
+            .and_then(Value::as_object);
+        let environment_id = source
+            .and_then(|source| source.get("environment_id"))
+            .and_then(Value::as_str)
+            .unwrap_or_default();
+        if environment_id.contains("aws") {
+            return VertexAuthSource::AwsWorkloadIdentity;
+        }
+        if source.is_some_and(|source| source.contains_key("executable")) {
+            return VertexAuthSource::ExecutableWorkloadIdentity;
+        }
+        return VertexAuthSource::IdentityPoolWorkloadIdentity;
+    }
+    if credential_type == Some("authorized_user") {
+        return VertexAuthSource::AuthorizedUser;
+    }
+    VertexAuthSource::ServiceAccount
+}
+
+pub async fn resolve_token(config: VertexAuthConfig) -> CoreResult<VertexToken> {
+    let credentials = resolve_credentials_input(config.credentials)?;
+    let source = classify_auth(credentials.as_ref());
+    let project_id = project_id(config.project_id, credentials.as_ref())?;
+    let cache_key = cache_key(credentials.as_ref(), &project_id);
+    let provider = cached_credentials(&cache_key)?;
+    let provider = match provider {
+        Some(provider) => provider,
+        None => {
+            let provider = build_credentials(source, credentials)?;
+            let access_token = provider.access_token().await.map_err(|error| {
+                CoreError::Auth(format!("Google token resolution failed: {error}"))
+            })?;
+            store_credentials(cache_key, provider.clone())?;
+            return Ok(VertexToken {
+                access_token: access_token.token,
+                project_id,
+            });
+        }
+    };
+    let access_token = provider
+        .access_token()
+        .await
+        .map_err(|error| CoreError::Auth(format!("Google token resolution failed: {error}")))?;
+    Ok(VertexToken {
+        access_token: access_token.token,
+        project_id,
+    })
+}
+
+fn build_credentials(
+    source: VertexAuthSource,
+    credentials: Option<Value>,
+) -> CoreResult<AccessTokenCredentials> {
+    let scopes = [CLOUD_PLATFORM_SCOPE];
+    match source {
+        VertexAuthSource::DefaultAdc => google_cloud_auth::credentials::Builder::default()
+            .with_scopes(scopes)
+            .build_access_token_credentials()
+            .map_err(|error| CoreError::Auth(format!("Google ADC resolution failed: {error}"))),
+        VertexAuthSource::AwsWorkloadIdentity
+        | VertexAuthSource::ExecutableWorkloadIdentity
+        | VertexAuthSource::IdentityPoolWorkloadIdentity => {
+            let value = credentials.ok_or(CoreError::MissingField("credentials"))?;
+            external_account::Builder::new(value)
+                .with_scopes(scopes)
+                .build_access_token_credentials()
+                .map_err(|error| {
+                    CoreError::Auth(format!(
+                        "Google external account resolution failed: {error}"
+                    ))
+                })
+        }
+        VertexAuthSource::AuthorizedUser => {
+            let value = credentials.ok_or(CoreError::MissingField("credentials"))?;
+            user_account::Builder::new(value)
+                .with_scopes(scopes)
+                .build_access_token_credentials()
+                .map_err(|error| {
+                    CoreError::Auth(format!("Google authorized-user resolution failed: {error}"))
+                })
+        }
+        VertexAuthSource::ServiceAccount => {
+            let value = credentials.ok_or(CoreError::MissingField("credentials"))?;
+            service_account::Builder::new(value)
+                .with_access_specifier(service_account::AccessSpecifier::from_scopes(scopes))
+                .build_access_token_credentials()
+                .map_err(|error| {
+                    CoreError::Auth(format!("Google service-account resolution failed: {error}"))
+                })
+        }
+    }
+}
+
+fn project_id(explicit: Option<String>, credentials: Option<&Value>) -> CoreResult<String> {
+    let project_id = explicit
+        .filter(|value| !value.trim().is_empty())
+        .or_else(|| {
+            credentials.and_then(|value| {
+                value
+                    .get("project_id")
+                    .and_then(Value::as_str)
+                    .map(str::to_owned)
+            })
+        })
+        .or_else(|| {
+            credentials.and_then(|value| {
+                value
+                    .get("quota_project_id")
+                    .and_then(Value::as_str)
+                    .map(str::to_owned)
+            })
+        })
+        .or_else(|| non_empty_env(GOOGLE_CLOUD_PROJECT))
+        .or_else(|| non_empty_env(GOOGLE_CLOUD_QUOTA_PROJECT));
+    project_id.ok_or(CoreError::MissingField("project_id"))
+}
+
+fn cache_key(credentials: Option<&Value>, project_id: &str) -> String {
+    let mut hasher = Sha256::new();
+    if let Some(credentials) = credentials {
+        hasher.update(credentials.to_string());
+    }
+    hasher.update(project_id);
+    format!("{:x}", hasher.finalize())
+}
+
+fn cached_credentials(key: &str) -> CoreResult<Option<AccessTokenCredentials>> {
+    let cache = VERTEX_CREDENTIALS_CACHE.get_or_init(|| Mutex::new(InMemoryCache::default()));
+    let mut cache = cache
+        .lock()
+        .map_err(|_| CoreError::Auth("Vertex credential cache lock poisoned".to_string()))?;
+    Ok(cache.get_cache(key))
+}
+
+fn store_credentials(key: String, credentials: AccessTokenCredentials) -> CoreResult<()> {
+    let cache = VERTEX_CREDENTIALS_CACHE.get_or_init(|| Mutex::new(InMemoryCache::default()));
+    let mut cache = cache
+        .lock()
+        .map_err(|_| CoreError::Auth("Vertex credential cache lock poisoned".to_string()))?;
+    cache.set_cache(key, credentials, None);
+    Ok(())
+}
+
+fn non_empty_env(name: &str) -> Option<String> {
+    env::var(name).ok().filter(|value| !value.trim().is_empty())
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use serde_json::json;
+
+    #[test]
+    fn classifier_preserves_external_account_dispatch_order() {
+        assert_eq!(
+            classify_auth(Some(&json!({
+                "type": "external_account",
+                "credential_source": {"environment_id": "aws1", "executable": {}}
+            }))),
+            VertexAuthSource::AwsWorkloadIdentity
+        );
+        assert_eq!(
+            classify_auth(Some(&json!({
+                "type": "external_account",
+                "credential_source": {"executable": {"command": "token"}}
+            }))),
+            VertexAuthSource::ExecutableWorkloadIdentity
+        );
+        assert_eq!(
+            classify_auth(Some(
+                &json!({"type": "external_account", "credential_source": {}})
+            )),
+            VertexAuthSource::IdentityPoolWorkloadIdentity
+        );
+    }
+
+    #[test]
+    fn classifier_covers_authorized_service_and_default_sources() {
+        assert_eq!(
+            classify_auth(Some(&json!({"type": "authorized_user"}))),
+            VertexAuthSource::AuthorizedUser
+        );
+        assert_eq!(
+            classify_auth(Some(&json!({"type": "service_account"}))),
+            VertexAuthSource::ServiceAccount
+        );
+        assert_eq!(
+            classify_auth(Some(&json!({"client_email": "test@example.com"}))),
+            VertexAuthSource::ServiceAccount
+        );
+        assert_eq!(classify_auth(None), VertexAuthSource::DefaultAdc);
+    }
+
+    #[test]
+    fn credential_input_reads_files_inline_json_and_objects() {
+        let path = std::env::temp_dir().join(format!("vertex-auth-{}.json", std::process::id()));
+        std::fs::write(&path, r#"{"type":"authorized_user"}"#).unwrap();
+        assert_eq!(
+            resolve_credentials_input(Some(VertexCredentialsInput::String(
+                path.to_string_lossy().into_owned()
+            )))
+            .unwrap(),
+            Some(json!({"type": "authorized_user"}))
+        );
+        std::fs::remove_file(path).unwrap();
+        assert_eq!(
+            resolve_credentials_input(Some(VertexCredentialsInput::String(
+                r#"{"type":"service_account"}"#.to_string()
+            )))
+            .unwrap(),
+            Some(json!({"type": "service_account"}))
+        );
+        assert_eq!(
+            resolve_credentials_input(Some(VertexCredentialsInput::Json(json!({
+                "type": "external_account"
+            }))))
+            .unwrap(),
+            Some(json!({"type": "external_account"}))
+        );
+    }
+
+    #[test]
+    fn credential_input_treats_empty_as_absent_and_rejects_invalid_json() {
+        assert_eq!(
+            resolve_credentials_input(Some(VertexCredentialsInput::String(" \n".to_string())))
+                .unwrap(),
+            None
+        );
+        assert!(matches!(
+            resolve_credentials_input(Some(VertexCredentialsInput::String("{".to_string()))),
+            Err(CoreError::Auth(_))
+        ));
+    }
+
+    #[test]
+    fn project_id_explicit_value_wins_over_credential_and_environment() {
+        let credentials = json!({"project_id": "credential-project"});
+        assert_eq!(
+            project_id(Some("explicit-project".to_string()), Some(&credentials)).unwrap(),
+            "explicit-project"
+        );
+        assert_eq!(
+            project_id(None, Some(&credentials)).unwrap(),
+            "credential-project"
+        );
+        assert_eq!(
+            project_id(None, Some(&json!({"quota_project_id": "quota-project"}))).unwrap(),
+            "quota-project"
+        );
+    }
+}