Short version: Only one thing on this page has a legal date on it, and that date is today. The EU AI Act's Article 50 transparency rules are now in force — if EU users can reach your AI, you owe them disclosure and machine-readable marking of AI-generated content. Everything else that happened this week was the price of intelligence moving, not the frontier of it: OpenAI cut the cheap tier hard, Anthropic shipped a frontier-adjacent Claude at flat pricing, and the largest open-weight model ever went public. So do the compliance work today, spend an hour re-pricing your routing this week, and don't rebuild your agent around any one model — the tier you'd pick is a moving target this month.

The one deadline: EU AI-transparency duties are live as of today#

As of August 2, 2026, the EU AI Act's Article 50 transparency obligations apply. Three duties matter for a builder:

  1. Disclose the AI. When a person interacts with an AI system (a chatbot, a voice agent), you must tell them — unless it's obvious from context.
  2. Mark the output. Generative-AI outputs must be marked as artificial in a machine-readable format. That covers synthetic audio, image, and video, and text published to inform the public on matters of public interest.
  3. Label deepfakes. Content that resembles real people, places, or events and is AI-manipulated must be clearly labeled.

The teeth: non-compliance carries penalties up to €15 million or 3% of worldwide annual turnover, whichever is higher. The reach: it's extraterritorial — a non-EU startup is covered if its output is used in the EU. The mercy: it's not retroactive — content generated before today isn't covered, so this is a go-forward pipeline change, not a back-catalogue cleanup.

What it means: this is the only item this week with a date attached, and the date is now. If EU users can sign up, add interaction disclosure and content marking to your generation path this week. We have a founder compliance checklist and a what-to-actually-ship guide for the machine-readable part.

The week the cheap tier moved: OpenAI cuts Luna ~80%#

On July 30, OpenAI cut API prices on the lower tiers of the GPT-5.6 family. As reported by Axios and VentureBeat: Luna fell ~80% (from $1.00 to $0.20 input and $6.00 to $1.20 output per million tokens), Terra fell ~20% ($2.50→$2.00 input, $15→$12 output), and flagship Sol held at $5/$30.

What it means: the floor dropped and the ceiling didn't, so the spread between "cheap enough for bulk grunt work" and "good enough for the task you can't get wrong" got wider. That's a routing signal, not a switch-everything signal. Re-run your cost-per-completed-task by task class — not per token — and re-route only the classes where Luna's new number actually wins your total bill. The sticker-versus-bill breakdown shows where the naive per-token math misleads.

The frontier held its price: Claude Opus 5#

On July 24, Anthropic shipped Claude Opus 5 at $5 input / $25 output per million — unchanged from Opus 4.8 and roughly half Fable 5's input price — and made it the default on Claude Max. Prompt caching still buys up to ~90% off cached reads; batch, ~50%.

What it means: unlike the OpenAI move, nothing about your Anthropic bill changed. If you benchmark agent quality against the frontier, re-baseline against Opus 5 — but there's no pricing pressure forcing a migration this week. For the head-to-head on when the cheap open tier is enough versus when you still want the frontier default, see Kimi K3 vs Opus 5.

Open weights hit 2.8 trillion: Kimi K3 goes public#

Around July 26–27, Moonshot AI published open weights for Kimi K3 — a ~2.8-trillion-parameter mixture-of-experts model (~104B active per token) with a 1M-token context, described as the largest open-weight model released to date and tuned for coding and agents.

What it means: it's a genuinely near-frontier model you can, in principle, run yourself and keep your data in-house. The catch is the same one every large open weight carries: at 2.8T parameters, self-hosting is real infrastructure, not a side project, and the build-vs-buy line only crosses in your favor at high, steady utilization. Trial it on a hosted endpoint first; decide on self-hosting once the meter proves it out; and read the repository LICENSE before you ship commercially — Moonshot's earlier K2 line carried a name-attribution clause above large revenue and usage thresholds. Our self-host-vs-API cost math and K3 founder guide go deeper. And the direction of the open-weights policy debate — where Anthropic just drew its line — is decoded in Amodei's position, for founders.

The plumbing locked down: MCP goes stateless, inference engines ship together#

Two infrastructure moves that don't make headlines but change what you build on:

What to do this week#

This is the same lesson the last month of releases keeps teaching: capability is leapfrogging weekly, so the thing that compounds isn't picking this week's winner — it's staying cheap to switch. For the wider read on how the model market got here, the week-of-July-20 edition is where this cycle's story starts.