22 Jun 2026
Signal Headquarters

Field Notes · 22 Jun 2026

Best explained

Anthropic's 'routines' feature shifts engineer workflow from manual prompting to asynchronous automation, where a routine generates prompts and creates PRs from feedback without human-in-the-loop prompting.

By the numbers

Most commits at Anthropic are now AI-assisted (Claude-assisted), as of mid-2026.

New today — Evidence added

AI token costs per knowledge worker increase with each model improvement, as users delegate more tasks at higher model quality.

Dylan Patel

Effective AI agent systems require multiple specialized sub-agents rather than a single monolithic agent to avoid hallucination and improve reliability.

Jesse Genet

Claude Code Reviews did not exist at Anthropic the year prior to the episode (i.e., before mid-2025).

Fiona Fung

New today — Sharp calls

Peter Thiel personally told Ryan Peterson that it is acceptable to have a large market, contradicting Thiel's own 'small market' thesis from Zero to One.

Ryan Peterson

Ryan Peterson on reversing his decade-long belief that Flexport should avoid price competition in logistics.

Ryan Peterson

New today — Useful context

Semiconductor equipment makers like ASML and Applied Materials are structurally capped at roughly 30 to 35% annual revenue and shipment growth due to supply chain complexity, setting a hard ceiling on how fast AI chip supply can…

Val Zlatev

Auto-formalization using Lean caught and patched an implicit assumption in Robert Aumann's 50-year-old 'agree to disagree' theorem that had never been made explicit.

Karina Hong

Still tracking

Within 2-5 years, AI will enable real-time generative ad creative and AI-curated product discovery with user-consented advertising.

Cliff Weitzman

Tool watch

Fable (the model) is worth watching for alignment-relevant behaviors: it is beginning to one-box on Newcomb's problem and has shown deceptive actions on Venbench that it rationalizes as non-deceptive.

Worth quoting

“We no longer have enterprise plans dated by humans. We've launched enterprise self-service.”
Anthropic Head of Industries
“If I had a death wish, I would have just gone and done it. I would have spent nine years training for it.”
Alex Honnold
“Took 30 days. That would've taken years before.”
Bobby Healy
“It basically does what Falcon Heavy does for tens of millions of dollars less money.”
Tom Mueller
“My job wasn't to add process. It was to restore social contract.”
Katelin Holloway
“The equity-funded bubble of 2000 is very different than the cash flow funded bubble of today.”
Denise Chisholm