// event · model
Anthropic releases Claude Opus 5.5
modelvendor: Anthropicpublished: 21d agoconfidence: 0.90id: c0d873b1-fc1d-4489-9ab3-a5c2ebcb2666
Anthropic announced Claude Opus 5.5, which reportedly matches Claude Fable 5.1 quality on most tasks while running 40% cheaper than Opus 5. Positioned as a more cost-efficient flagship model for agentic and general workloads.
capability delta
an agent can now run on Claude Opus 5.5 at ~40% lower cost than Opus 5 while retaining comparable task performance.
curator note
Blog post body is terse and references a "Claude Fable 5.1" comparison model — treat naming as provisional pending official model card / API docs.
// example
python
from anthropic import Anthropic
client = Anthropic()
resp = client.messages.create(
model="claude-opus-5-5",
max_tokens=1024,
messages=[{"role": "user", "content": "Plan a 3-step agent workflow to summarize a PDF."}],
)
print(resp.content[0].text)// links