Releasesby GlyphNo other model reads thinking blocks from Claude Fable 5.2 or Claude Mythos 5.2
No other model reads thinking blocks from Claude Fable 5.2 or Claude Mythos 5.2. When a conversation moves from either one to a model outside this pair, the API drops those blocks. That includes a move to Claude Opus 5.5 or Claude Fable 5.1. The request still succeeds. See Switching models mid-conversation.
Also shipped Nov 9, 2026Anthropic in November 2026 →
AlloyDB AI smart batching and sentiment analysis are generally available
AlloyDB AI smart batching for AI functions and the ai.analyze_sentiment function are now generally available on PostgreSQL 17 and later. Smart batching improves query performance by offloading AI operations asynchronously.
BigQuery compute cost attribution is available in preview
BigQuery now supports compute cost attribution in preview, allowing users to track billed compute charges at the project level based on reservation capacity usage for FinOps reporting.
BigQuery jobs explorer performance troubleshooting is generally available
BigQuery jobs explorer now provides generally available tools for troubleshooting query performance and comparing job and system performance to diagnose regressions.
BigQuery pipeline task concurrency limits are generally available
Users can now specify the maximum number of concurrently executed tasks when creating or scheduling BigQuery pipelines.
BigQuery adds Zstandard compression functions in preview
BigQuery now supports Zstandard (Zstd) compression and decompression functions for bytes and string values in GoogleSQL, currently available in preview.
AWS Glue adds 100 new native connectors for popular SaaS applications
AWS Glue now includes 100 native connectors for SaaS and REST API applications, enabling data integration without custom code. These connectors allow teams to reuse connections across ETL jobs with existing permission models.
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Anthropic launches Claude Fable 5.2 and Claude Mythos 5.2
Anthropic has released Claude Fable 5.2 and Claude Mythos 5.2, featuring a 1M token context window and adaptive thinking. These models are available across major cloud platforms.
Claude Fable 5.2 and Claude Mythos 5.2 enforce the prefix check for every account, whatever its age
Claude Fable 5.2 and Claude Mythos 5.2 enforce the prefix check for every account, whatever its age. Claude Fable 5.1 returns the error by default on accounts created on or after August 31, 2026 (see When prefix_mismatch_behavior is unset).
On the Claude API and Claude Models on Google Cloud (Google managed), a conversation that moves onto Claude
On the Claude API and Claude Models on Google Cloud (Google managed), a conversation that moves onto Claude Fable 5.2 or Claude Mythos 5.2 keeps the reasoning from other models, including Claude Opus 5.5, Claude Sonnet 5.5, and Claude Haiku 5.5.
Claude Fable 5.2 and Claude Mythos 5.2 support computer use through the computer_toolset_20260801 toolset
Claude Fable 5.2 and Claude Mythos 5.2 support computer use through the computer_toolset_20260801 toolset. A request that declares the earlier computer_20251124 tool returns a 400 error on every platform except Amazon Bedrock, where the earlier tool still works. See Migrate from computer_20251124.
With the advisor tool, which is in beta, a Claude Fable 5.2 or Claude Mythos 5.2 executor accepts only Claude
With the advisor tool, which is in beta, a Claude Fable 5.2 or Claude Mythos 5.2 executor accepts only Claude Fable 5.2 or Claude Mythos 5.2 as its advisor. Any other advisor returns a 400 error, so set the advisor’s model to one of these two models when you move an executor to them. Every executor model accepts Claude Fable 5.2 as its advisor.
Both models require 30-day data retention, like Claude Fable 5.1 and Claude Mythos 5.1
Both models require 30-day data retention, like Claude Fable 5.1 and Claude Mythos 5.1. They aren’t available under zero data retention unless expressly authorized by Anthropic. See Model-specific data retention requirements.
Thinking blocks that Claude Fable 5.2 and Claude Mythos 5.2 produce work only in the account that produced
Thinking blocks that Claude Fable 5.2 and Claude Mythos 5.2 produce work only in the account that produced them, or in an account linked to it. See Preserved thinking.
We’ve launched fast mode for Claude Fable 5.2 in Messages API requests on the Claude API
We’ve launched fast mode for Claude Fable 5.2 in Messages API requests on the Claude API. Fast mode delivers up to 2.5x higher output tokens per second, at $16 USD per MTok of input and $80 USD per MTok of output. Set speed: "fast" on your request, with no beta header.