diff --git a/install.ps1 b/install.ps1
index e8d89d8..0884242 100644
--- a/install.ps1
+++ b/install.ps1
@@ -357,6 +357,9 @@ if ($Global) {
     $envObj | Add-Member -NotePropertyName ANTHROPIC_AUTH_TOKEN       -NotePropertyValue $ApiKey     -Force
     $envObj | Add-Member -NotePropertyName ANTHROPIC_MODEL            -NotePropertyValue $Model      -Force
     $envObj | Add-Member -NotePropertyName ANTHROPIC_SMALL_FAST_MODEL -NotePropertyValue $Model      -Force
+    # The gateway rejects Claude Code's adaptive-thinking parameter; see the
+    # launcher for the full note. Remove when the gateway accepts "adaptive".
+    $envObj | Add-Member -NotePropertyName MAX_THINKING_TOKENS         -NotePropertyValue '0'        -Force
     $cfg | Add-Member -NotePropertyName env -NotePropertyValue $envObj -Force
 }
 Write-RawText $Settings ($cfg | ConvertTo-Json -Depth 100)
diff --git a/install.sh b/install.sh
index c20dec9..8a4e663 100755
--- a/install.sh
+++ b/install.sh
@@ -481,7 +481,8 @@ write_settings() {
     "ANTHROPIC_BASE_URL": "$GATEWAY_URL",
     "ANTHROPIC_AUTH_TOKEN": "$API_KEY",
     "ANTHROPIC_MODEL": "$MODEL",
-    "ANTHROPIC_SMALL_FAST_MODEL": "$MODEL"
+    "ANTHROPIC_SMALL_FAST_MODEL": "$MODEL",
+    "MAX_THINKING_TOKENS": "0"
   },
   "statusLine": { "type": "command", "command": "'$statusline_cmd'" }
 }
@@ -510,6 +511,9 @@ if os.environ["QC_GLOBAL"] == "1":
     env["ANTHROPIC_AUTH_TOKEN"] = os.environ["QC_TOKEN"]
     env["ANTHROPIC_MODEL"] = os.environ["QC_MODEL"]
     env["ANTHROPIC_SMALL_FAST_MODEL"] = os.environ["QC_MODEL"]
+    # The gateway rejects Claude Code's adaptive-thinking parameter; see the
+    # launcher for the full note. Remove when the gateway accepts "adaptive".
+    env["MAX_THINKING_TOKENS"] = "0"
 tmp = path + ".qbraid-code.tmp"
 with open(tmp, "w") as fh:
     json.dump(data, fh, indent=2)
diff --git a/qbraid-code b/qbraid-code
index 7df53d0..6be6a31 100755
--- a/qbraid-code
+++ b/qbraid-code
@@ -128,6 +128,14 @@ command -v claude >/dev/null 2>&1 || {
 # accepts. ANTHROPIC_API_KEY would work too, but it makes Claude Code ask the
 # user to approve a custom API key on first run — a prompt with no good answer
 # for someone who just wants to start working.
+#
+# MAX_THINKING_TOKENS=0: recent Claude Code sends `thinking: {type: "adaptive"}`,
+# which the gateway's Anthropic surface rejects (it accepts enabled|disabled —
+# qbraid-api ai-request.validators.ts), turning every request into a 400.
+# FORCED, not defaulted: an inherited MAX_THINKING_TOKENS from the user's
+# shell re-enables thinking and turns every request into that 400. Remove the
+# whole line once the gateway accepts "adaptive".
+MAX_THINKING_TOKENS=0 \
 ANTHROPIC_BASE_URL="$BASE_URL" \
 ANTHROPIC_AUTH_TOKEN="$TOKEN" \
 ANTHROPIC_MODEL="$MODEL" \
diff --git a/qbraid-code.cmd b/qbraid-code.cmd
index 7073698..e8ae7b9 100644
--- a/qbraid-code.cmd
+++ b/qbraid-code.cmd
@@ -50,6 +50,11 @@ rem ANTHROPIC_AUTH_TOKEN sends `Authorization: Bearer <key>`, which the gateway
 rem accepts. ANTHROPIC_API_KEY would work too, but it makes Claude Code ask the
 rem user to approve a custom API key on first run - a prompt with no good answer
 rem for someone who just wants to start working.
+rem MAX_THINKING_TOKENS=0: recent Claude Code sends thinking type "adaptive",
+rem which the gateway rejects (accepts enabled/disabled only) - every request
+rem would 400. Forced: an inherited value re-enables thinking and breaks every
+rem request. Remove once the gateway accepts adaptive.
+set "MAX_THINKING_TOKENS=0"
 set "ANTHROPIC_BASE_URL=%QBRAID_CODE_BASE_URL%"
 set "ANTHROPIC_AUTH_TOKEN=%QBRAID_CODE_TOKEN%"
 set "ANTHROPIC_MODEL=%QBRAID_CODE_MODEL%"