# AI news, Thursday, 3 September 2026

Compiled by Richard Brooks's AI news desk. Canonical: https://richard-brooks.com/ai-news/2026-09-03/

## Anthropic makes Claude Fable 5.1 generally available

Models. Fable 5.1 is GA; Mythos 5.1 stays in trusted access. Cache reads drop 75% to $0.25 per MTok, with an EFS/ZDR path and an EU AI Act watermark preview.

Source: Anthropic, https://www.anthropic.com/claude-fable-and-mythos-5-1

## Google adds agentic video understanding to Gemini

Tools. Gemini Flash models can run an agentic video loop over dynamic frames, audio and transcripts, cutting tokens and cost while lifting accuracy.

Source: Google, https://blog.google/innovation-and-ai/models-and-research/gemini-models/introducing-agentic-video-in-gemini/

## HarnessDev benchmarks agent harness Creation and Evolution

Agents. Benchmark treats the runnable agent harness, not only task outputs, as the unit of eval. Model-built harnesses trail humans on code and search.

Source: arXiv, https://arxiv.org/abs/2609.01437

## Meta ships Muse Voice Transcribe

Language. Streaming ASR with 20-plus speaker diarisation and endpointing in one pass, 70-plus languages, native code-switching, live in Meta AI Mac dictation and Muse Code.

Source: Meta, https://research.meta.ai/blog/introducing-muse-voice-transcribe

## OpenAI designates Astra as Critical cyber model

Models. Upcoming Astra is the first Critical cyber model under the Preparedness Framework. Stronger refusals and chain-of-thought monitoring may pause long-running agent tasks.

Source: OpenAI, https://openai.com/index/path-to-astra/

## Tether open-sources AfriSLM and EuroNano MT

Language. On-device MT for English and 19 Sub-Saharan African languages, plus European Nano models, with quality-estimation filtering that lifts small models on FLORES.

Source: Tether, https://tether.io/news/tether-releases-open-source-ai-translation-models-for-african-and-european-languages/