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AWS bedrock documentation change

Service: bedrock · 2026-06-10 · Documentation low

File: bedrock/latest/userguide/model-cards-anthropic.md

Summary

Added new Claude Mythos 5 and Claude Fable 5 models, introduced 'Billing notes' section explaining refusal billing behavior

Security assessment

Billing clarification for refused requests describes accounting behavior rather than security features. New model introductions don't include security-specific documentation.

Diff

diff --git a/bedrock/latest/userguide/model-cards-anthropic.md b/bedrock/latest/userguide/model-cards-anthropic.md
index f9f372a6e..07df0cab8 100644
--- a//bedrock/latest/userguide/model-cards-anthropic.md
+++ b//bedrock/latest/userguide/model-cards-anthropic.md
@@ -6,0 +7,2 @@
+Billing notes
+
@@ -12,0 +15,2 @@ The following Anthropic models are available in Amazon Bedrock:
+[Claude Mythos 5](./model-card-anthropic-claude-mythos-5.html)| Claude Mythos 5 is Anthropic's most capable model for cybersecurity and life sciences, including vulnerability discovery, drug design, and biodefense screening.  
+[Claude Fable 5](./model-card-anthropic-claude-fable-5.html)| Claude Fable 5 is Anthropic's next-generation model for complex knowledge work and coding, capable of sustained autonomous operation across multi-day tasks.  
@@ -25,0 +30,9 @@ The following Anthropic models are available in Amazon Bedrock:
+## Billing notes
+
+The following billing behaviors apply specifically to Anthropic models on Amazon Bedrock:
+
+  * **Refused requests (all Anthropic models on`bedrock-mantle`):** When a request is refused by a content classifier before inference begins, no input or output tokens are billed. Mid-stream refusals — where the classifier fires after output has begun streaming — are billed for tokens consumed before the block. Both refusal types return `stop_reason: "refusal"` in the response.
+
+
+
+
@@ -34 +47 @@ Titan Embeddings G1 - Text v2
-Claude Opus 4.8
+Claude Mythos 5