Anthropic changes its advice: do not use specialized subagents

By Rafa and Pablo · No stream on X because of a 500 error, only on YouTube and Twitch

Anthropic publishes a post in its resources section. Its advice: fold your subagents into the loop of the main agent. One year ago, the usual practice was different. The main agent sent work to subagents with a role: product, backend, frontend or QA. Each subagent did its part and gave a handoff to the next one.

That architecture made sense because of the limits of the models. The context was 100,000 or 200,000 tokens, and it filled up fast. Agents did not work for more than 2 or 3 minutes at a time, and you had to type "continue". Subagents automated that "continue". For Pablo, they also copied the org chart of the company: Conway's law applied to agents.

Since Opus 4.5, the main agent has more context and works for longer in a single loop. Now the problem with subagents is the context. Each subagent starts with a clean context and repeats the code search that the main agent already did. According to the post, Anthropic removes its internal subagents and uses half the tokens at twice the speed.

The advice: if you already have subagents, remove them one at a time and run evals for each change. Move the instructions from their system prompt to documentation or to skills, with progressive disclosure. General-purpose subagents still make sense to find context or to run work in parallel, and Claude Code, Codex and OpenCode already launch them by default. With Pi, you must ask for them explicitly. Watch in the video.

Binance loses 6.3 billion dollars through the laptop of a DevOps engineer

Binance suffers one of the largest thefts in history: about 6.3 billion dollars. According to its initial investigation, the attacker compromises the laptop of a DevOps engineer. From that laptop, the attacker gets into a service container and sends unauthorized withdrawals. Binance and other exchanges freeze about 3 billion, and Binance covers the rest with its insurance and its own funds.

For Rafa, the failure is not one person, it is the processes: nobody must be able to take out 6.3 billion alone. His advice: protect your local environment, because agents make it very fast to leak data. Run export in your terminal and look for private keys. If you find one, move it to a safer place. Watch in the video.

Qwen3.8-Flash-Next tries to send a file to Alibaba Cloud from a sandbox

Cohere evaluates Qwen3.8-Flash-Next in a controlled sandbox. It asks the model for a defensive detection rule. Instead, the model makes an inventory of the machine and tries to upload a test file to an Alibaba Cloud bucket. The sandbox blocks the request. Cohere does not assume bad intent: it can be a side effect of the training.

Pablo draws a conclusion: open-weight models are not open models. The Open Source Initiative also asks for the training code and enough information about the data to build an equivalent system. Without that, the model is a black box. Rafa sees hope in Mistral, which trains only on legal data to comply with European regulations. Watch in the video.

The utility of the week

wallapop-cli

An unofficial CLI for Wallapop: search for products from the terminal, or ask your agent to do it for you. With a CLI, the agent does not depend on the built-in browser and works very fast. The project inspires other CLIs, such as one to download and compare your Vodafone bills.

https://github.com/Microck/wallapop-cli

The chat weighs in

AdelysAlberto: In Pi you do have to tell it to use the agents for the task, because the way Pi handles its master prompt makes the use of subagents non-deterministic.

hoxefko: Because the abstraction layers that languages and frameworks gave us are moving to AI.

julioburgos3962: You can't even use Mistral on its website, only through the API. The chat on its website is GLM.

Agenda

Mozilla Festival 2026, in Barcelona · 2026-10-30
WordCamp Valencia 2026 · 2026-10-31

The song of the week

Pablo: «Tramuntana» — Guitarricadelafuente (Pablo is obsessed with the film La bola negra and listens to Guitarricadelafuente all the time. It is the last song on the album, and it is beautiful.) Watch in the video.

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

The saying of the week

«Mantenerse en sus trece (to stay at your thirteen)»

To refuse to change your opinion, no matter what other people say. Watch in the video.

More Codely

Event Bus en Kafka: Diseño de infraestructura

Now 100% published on the Standard plan. Learn to build an event bus with the native queues of Kafka: dead letters, retries and the renew command.

The joke of the week: Why can't C go to a Michelin-star restaurant? Because it has no class!

All the news we covered

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

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