Sonnet 5: Opus quality at «half the price»… with two hidden catches

From the Friday July 3rd café · Today, black coffee: Javi flying solo — Rafa is back very soon

Anthropic launches Sonnet 5, a new version of its mid-tier family, promising to close the gap with Opus while keeping Sonnet's price: performance close to Opus 4.8 on agentic benchmarks, 1 million tokens of context and the new default model in Claude Code for Pro users.

But watch out for the «Opus quality for 60% less» headlines. First catch: the launch price ($2 input / $10 output per million tokens) is subsidized only until August 31st; after that, $3 and $15. Many comparisons out there are being made against the discounted price.

Second catch: the new tokenizer consumes 40% more tokens in English and 33% more in Spanish, according to Simon Willison. And your codebase is in English even if you prompt in Spanish, so the price difference is not that big anymore. They pee on us and tell us it's raining.

The café's conclusion: there is no magic wand. Run evals on your own codebase and compare price per task, not per token. Meanwhile, OpenAI answers with GPT Terra, Luna and Sol in preview. Watch in the video.

Git 2.55 takes out the scalpel: fixup to amend a single commit

A new minor version of our dearly beloved version control: multipack indexes to go faster and, above all, the fixup option in git history to change an earlier commit without rebasing all the others. The classic «I left out something that actually belonged in the first commit», and boom. Fully on board with that. Watch in the video.

Vercel open-sources konsistent, the conventions linter

Now open source: the CLI linter that AI SDK and Chat SDK use to enforce structural conventions in TypeScript codebases: deterministic, fast and covering patterns that TypeScript and ESLint don't model. They even ship a skill to generate your first konsistent.json. Deterministic feedback for humans and agents: top notch. Watch in the video.

The utility of the week

PhoneFlow

The Open Source Voice Agent Platform, by Adrià Blancafort (Factorial). Like an n8n built concretely and specifically for voice agents: you connect your number via SIP, manage it with your agent and monitor every call and its cost. «As a public version one, I'm turbo-thrilled: there's a spectacular amount of work in it.»

getphoneflow.com

The chat weighs in

@mcruffian: «I don't know if I fancy a future where I have to calculate all this crap every time a new model comes out, as if I were negotiating wheat by the ton…» — on Sonnet 5 pricing

@Jaime-c7v5z: «Ever since Elon became a trillionaire, $4,500 feels free/no-setup to him» — on the X MCP

@rafaoe: «I'm around!!! Coming back sooon!!» — replying to someone asking where Rafa is

The song of the week

Javi: «Si Miro Patrás» — La Plazuela (Amazing band: it takes me back to a lot of places where I've been very happy) Watch in the video.

The café's music playlist: cdly.to/playlist

The saying of the week

«Parto largo y parto malo, hija al cabo»

Spanish saying: after a long and painful process, the outcome still isn't the one you were hoping for. Watch in the video.

More Codely

Programación Agéntica

Caches, costs and agent harness so you don't overpay for tokens. Each café's summary, now also in your inbox: codely.com/newsletter

The joke of the week: Do you know why git jokes are never funny? Because everyone has their own version.

All the news we covered

#CaféConCodely · @CodelyTV · Previous cafés: cdly.to/cafe

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