diff --git a/crates/anthropic/src/anthropic.rs b/crates/anthropic/src/anthropic.rs
index c499e79e12..cc33e4f06a 100644
--- a/crates/anthropic/src/anthropic.rs
+++ b/crates/anthropic/src/anthropic.rs
@@ -560,6 +560,15 @@ pub async fn stream_completion_with_rate_limit_info(
                             .strip_prefix("data: ")
                             .or_else(|| line.strip_prefix("data:"))?;
 
+                        // Some proxies and gateways append `data: [DONE]` as a
+                        // stream-termination sentinel (an OpenAI convention).
+                        // It is not part of the Anthropic streaming spec and is
+                        // not valid JSON, so skip it to avoid a spurious
+                        // deserialization error.
+                        if line.trim() == "[DONE]" {
+                            return None;
+                        }
+
                         match serde_json::from_str(line) {
                             Ok(response) => Some(Ok(response)),
                             Err(error) => Some(Err(AnthropicError::DeserializeResponse(error))),
diff --git a/crates/google_ai/src/google_ai.rs b/crates/google_ai/src/google_ai.rs
index 9cf4fdc494..71c0d4e031 100644
--- a/crates/google_ai/src/google_ai.rs
+++ b/crates/google_ai/src/google_ai.rs
@@ -42,6 +42,15 @@ pub async fn stream_generate_content(
                 match line {
                     Ok(line) => {
                         if let Some(line) = line.strip_prefix("data: ") {
+                            // Some proxies and gateways append `data: [DONE]` as a
+                            // stream-termination sentinel (an OpenAI convention).
+                            // Google's streaming spec does not include this sentinel,
+                            // but we tolerate it here for the same reason as the
+                            // anthropic crate: proxies that inject it would otherwise
+                            // cause a spurious JSON deserialization error.
+                            if line.trim() == "[DONE]" {
+                                return None;
+                            }
                             match serde_json::from_str(line) {
                                 Ok(response) => Some(Ok(response)),
                                 Err(error) => Some(Err(anyhow!(format!(