Onchain payments can settle instantly and still fall short if they are missing context.
Arc transaction memos add structured context to contract calls so payments, payouts, and financial activity are easier to reconcile, attribute, and connect to internal systems.
→ Invoice IDs
→ Payout references
→ Customer or ledger keys
→ Memo events for indexing and analytics
Fast settlement is only part of the job. Arc is built to make onchain finance usable.
https://t.co/YAQLN8mHw1
Introducing Claude Fable 5: a Mythos-class model that we’ve made safe for general use.
Its capabilities exceed those of any model we’ve ever made generally available.
Introducing Agent Arena: real-world agentic evals at scale.
How do you evaluate agents doing actual work? We measure millions of live sessions where real users accomplish real tasks.
On Arena, models now get web search, filesystem, and terminal tools to complete complex workflows: writing code, creating slide deck, researching the web, building apps, and analyzing documents.
Every session produces rich signals. Users iterate with the agent turn-by-turn: approving, editing, correcting, praise or expressing frustration. The environment gives feedback too: shell errors, tool failures, recovery attempts, and more.
Our leaderboard measures each model's agentic performance using causal inference across five signals: task success, steerability, error recovery, user praise vs. complaint, and tool hallucination.
This leaderboard snapshot is built from 300K+ tasks, 2M+ tool calls, and 40M lines of code by agents.
Top labs in Agent Arena:
- #1 @OpenAI: GPT-5.5 (High)
- #2 @AnthropicAI: Claude-Opus-4.7 (Thinking)
- #3 @Zai_org: GLM-5.1
- #4 @GoogleDeepMind: Gemini-3.1-Pro
- #5 @Kimi_Moonshot: Kimi-K2.6
More analysis in the thread, with the full technical blog below.
Applications are open for the first Arc Programmable Money Developer Series with @encodeclub.
The program starts with a 4-week async bootcamp, followed by a hackathon and accelerator track, with London workshops and activations at Encode Hub.
Build with:
→ Stablecoin-native apps
→ Cross-border payments
→ Multi-currency flows
→ Agent-driven finance
→ Onchain financial workflows
Bootcamp applications are open: https://t.co/jl7SQsY4ZL