OpenAI

GPT-6 Astra: A new generation of intelligence

Nova generacija inteligence

Predstavljamo GPT‑6 Astra, najinteligentnejši in najbolj usklajen model na svetu.

GPT‑6 Astra združuje leta raziskav in velike naložbe v začetno usposabljanje, okrepljeno učenje in usklajevanje. Astra dosega najsodobnejše rezultate na področjih uporabe računalnika, brskanja po spletu, programskega inženirstva, kibernetske varnosti, znanosti in profesionalnega dela. Astra z rezultatom 98 % dosega skoraj popolno uspešnost na FrontierMath Tier 4, potem ko je že pomagala rešiti dolgoletne odprte probleme v matematiki. Astra tudi dosega zasičenost na ARC-SUI-3 z rezultatom 99,9 % in na ExploitBench z rezultatom 100 %. Postavlja tudi novo prelomno pri uporabi računalnika in brskalnika ter najzahtevnejše profesionalno delo opravlja z neprimerljivo hitrostjo, natančnostjo in presojo. 

GPT‑6 Astra se danes uvaja za omejen nabor organizacij, v naslednjih dneh pa bo na voljo vsem uporabnikom paketov ChatGPT Plus, Pro, Business in Enterprise ter prek API-ja OpenAI, Microsoft Azure in AWS Bedrock.

»Na preizkusu ARC-SUI-3 je Astra na 96 % ravneh presegla naše izhodišče za učinkovitost človeških dejanj in tako dejansko dosegla enakovrednost s človekom na tem preizkusu. Ne le da je to najboljši model, kar smo jih kdaj preizkusili, temveč predstavlja tudi pomemben preskok v zmogljivosti prelomnih modelov – ne le v sposobnosti navigiranja po novih okoljih in njihovega reševanja, temveč tudi v učinkovitosti učenja, kako to storiti.«
Greg Kamradt, ARC Prize Foundation

Astra je naš najbolj usklajen model, ki se je bistveno izboljšal pri razumevanju namena uporabnikov in vedenja modela – zato lahko naloge z večjim zaupanjem prepustite presoji Astre. Kot enega od načinov, na katerega to preizkušamo, smo na podlagi incidenta Hugging Face razvili novo vrednotenje, ki preverja, ali bo model, ki se sooči s težko ali nemogočo nalogo, presegel svoj predvideni obseg. V primerjavi z modelom GPT‑5.6 Sol, ki je brez zaščitnih ukrepov v produkcijskem okolju pooblaščeni cilj presegel v 48 % primerov, je GPT‑6 Astra to storil v 0 % primerov.

Najboljši model za uporabo računalnika na svetu

GPT‑6 Astra pomeni novo prelomno na področju hitrosti, natančnosti in varnosti pri uporabi računalnika. Lahko poskrbi za zamudna opravila, kot so izpolnjevanje spletnih obrazcev, posodabljanje evidenc strank v CRM-ju in urejanje vašega koledarja. Lahko opravlja spletne raziskave in pripravi osnutke povzetkov v vaši e-pošti ali urejevalniku dokumentov. Lahko analizira znanstvene podatke, ustvari grafe, izdela spletno mesto in zažene preverjanja kakovosti osprednjega vmesnika (frontend), da zagotovi, da vse funkcije na tem spletnem mestu delujejo. Pomaga vam lahko samostojno nameščati in preizkušati programsko opremo ter odpravljati težave, ki jih vidite na zaslonu. Te izboljšave se odražajo tudi v naših najsodobnejših rezultatih evalvacij.

Te izboljšave prinašajo tudi znatno večjo učinkovitost pri dejanskih nalogah umskega dela. V simulacijah zakasnitve na OSWorld 2.0 Astra dosega boljšo uspešnost pri uporabi računalnika v približno 47 % krajšem času na nalogo kot GPT‑5.6 Sol, z rezultatom 72,6 % pri približno 40 minutah na nalogo, v primerjavi z 65,7 % pri približno 75 minutah.3

Zmogljivosti GPT‑6 Astra za uporabo računalnika so razvidne iz rezultatov na različnih področjih, vključno z razvojem iger, elektrotehniko in vsakodnevnim delom z znanjem:

Alongside Astra, we are also updating the Codex harness to significantly improve the speed of computer use. Combined with Astra’s efficiency, this translates to a 1.9x faster task completion compared to the current GPT‑5.6 Sol experience, on the Mind2Web benchmark. The model’s improvements on speed mean it can take on many time-consuming life tasks for you, faster than you can.4

»Model GPT‑6 Astra na dan uvedbe integriramo v Devinovo ogrodje, kjer na našem internem merilu uspešnosti pri preizkušanju dosega najsodobnejšo zmogljivost. Njegove odlične zmožnosti uporabe računalnika, pisanja in razumevanja kodne zbirke so izboljšale preizkušanje že takoj ob prvi uporabi: videoposnetkom je opazno lažje slediti, poročila pa so jasnejša in bolj jedrnata.«
Silas Alberti, višji podpredsednik za raziskave, Cognition

Skokovita sprememba v strokovnem delu

GPT‑6 Astra združuje napredek pri uporabi računalnika s ciljno usmerjenim usposabljanjem za profesionalna okolja, da bi pomagal pri reševanju kompleksnih delovnih nalog. Združuje inteligenco, potrebno za reševanje kompleksnih problemov, z zmožnostjo izvajanja večstopenjskih delovnih tokov ter ustvarjanja dodelanih dokumentov, preglednic in predstavitev.

GPT‑6 Astra je naš najboljši model za upoštevanje obstoječih predlog ter ustvarjanje dobro postavljenih diapozitivov, ki s strukturirano pripovedjo jedrnato podajajo ključne točke. Ustvarja jasne, dobro strukturirane dokumente, predstavitve, preglednice in analize, ki sledijo vašim predlogam ter se ujemajo z vašim slogom pisanja in vizualnim slogom. Astra je usposobljena tudi za to, da v izhodne rezultate vključi samo tisti kontekst, ki je pomemben, namesto da bi ponavljala informacije, ki za trenutno nalogo niso potrebne. Vse to pomeni, da lahko ustvari bolj neposredno uporabne artefakte, ki ustrezajo vašemu poslovnemu kontekstu in standardom.

GPT‑6 Astra prinaša tudi boljšo vizualno presojo pri spletnih mestih, igrah, aplikacijah in upodobitvah, ki jih ustvarja. S funkcijo Sites(odpre se v novem oknu) v ChatGPT‑ju lahko Astra neposredno iz poziva ustvarja, gosti in deli spletna mesta, spletne aplikacije in igre.

»Astra nam daje pomembno prednost tako pri zmogljivosti kot pri učinkovitosti. Uspešno izvaja naše najkompleksnejše ustvarjalne poteke dela, pri tem pa uporablja do 20 % manj žetonov kot drugi modeli, ki smo jih preizkusili. Najpomembneje pa je, da to za naše stranke pomeni kakovostnejše rezultate.«
Alex Mashrabov, izvršni direktor in soustanovitelj, Higgsfield AI

Kadar navodila dopuščajo različne razlage, GPT‑6 Astra sprejema pravilne odločitve bolje kot prejšnji modeli. Uporablja kontekst, da zapolni običajne vrzeli, in postavlja ciljno usmerjena vprašanja, kadar bi odgovor lahko spremenil izid. V Codexu lahko asinhrono postavlja vprašanja, medtem ko nadaljuje delo, ki ni odvisno od vašega odgovora. Če ne odgovorite, po potrebi nadaljuje s smiselnimi predpostavkami, pri odločitvah z večjimi posledicami pa počaka na vaš odziv.

Spodnji primeri prikazujejo, kako Astra sodeluje pri vsakodnevnih nalogah, kjer lahko manjkajoče informacije bistveno spremenijo odgovor.

Astra je tudi boljša pri ohranjanju usmerjenosti, ko se naloga razvija. Prejšnji modeli so usmerjevalna sporočila včasih obravnavali kot nov cilj ter pri tem izgubili sled prvotni zahtevi ali prejšnjim omejitvam. Astra vključuje nove zahteve, na zahtevo spremeni smer in odgovarja na stranska vprašanja, ne da bi pri tem opustila širšo nalogo.

»Astra predstavlja znatno izboljšanje kakovosti v primerjavi z GPT‑5.6 Sol pri zahtevnih pravnih nalogah. V našem zgodnjem preizkušanju je Astra izstopala po tem, da se pravnega dela loteva tako kot razsoden odvetnik: ločuje dokumente od uveljavljenih zapisov, razkriva neutemeljene predpostavke in vrzeli pretvarja v konkretna izhodišča za pripravo besedila.«
Niko Grupen, vodja uporabnih raziskav, Harvey

Programiranje

GPT‑6 Astra je doslej najboljši model za programsko inženirstvo.

1 od 2
»GPT‑6 Astra pri naših internih primerjalnih preizkusih kodiranja zagotavlja najsodobnejšo zmogljivost ter pri vrednotenjih intuicije trgovanja v primerjavi z GPT‑5.6 Sol kaže jasen napredek. Pri uporabi za agentsko kodiranje GPT‑6 Astra komunicira na način, ki mu razvijalci lažje sledijo, in ustvarja kodo, ki za doseganje kakovosti za produkcijsko okolje zahteva manj ponovitev.«
John Crepezzi, pomočniki z umetno inteligenco, Jane Street

Z Astro uvajamo nov način, s katerim Codex ohranja in pridobiva kontekst, ko se kontekstno okno zapolni. V preteklosti so modeli uporabljali kompaktiranje za povzemanje dela med dolgimi sejami, na primer pri odpravljanju zapletenih težav ali obsežnih refaktorizacijah. Pri vsakem kompaktiranju se lahko izpustijo podrobnosti o tem, zakaj je popravek spodletel ali kako se komponenta obnaša. V Codexu lahko Astra vodi zapiske prek kontekstnih oken ter tako ohranja zbrane podrobnosti, ne da bi jih vedno znova stiskala v en sam povzetek. Prejšnja kontekstna okna je še vedno mogoče preiskovati, zato lahko Astra najde zahteve ali rezultate preizkusov iz prejšnjih sporočil in izhodov orodij – tudi če te informacije niso bile zajete v njenih zapiskih. To eksperimentalno funkcijo lahko omogočite v svoji datoteki Codex config.toml,(odpre se v novem oknu) in to bo v prihodnjih tednih postalo privzeto za Astro.

Spodbujanje znanstvenih odkritij

»Zgodba je: konec ene dobe, začetek druge.«
Greg Burnham, EpochAI

GPT‑6 Astra is a major advance for scientific discovery, mathematics, and health. Today, we’re sharing two further results on the gaps between prime numbers.9 in 10

Astra also sets new records across a suite of math and science evaluations.

Astra lahko pomaga pri praktičnem delu v ozadju znanstvenih odkritij. Z združevanjem znanstvenega sklepanja in uporabe računalnika lahko neposredno deluje v specializirani programski opremi za pregledovanje podatkov in raziskovanje rezultatov ter raziskovalcem pomaga oceniti dokaze in se odločiti, kaj raziskati naprej.

Kibernetska varnost

As we discussed in our safety update, Astra is a significant jump in cyber capabilities and meets the Critical threshold in cybersecurity under our Preparedness Framework. Its ability to identify and develop zero-day exploits can help defenders find and patch weaknesses, but it also creates a need for stronger safeguards. To understand how far these capabilities extend, we ran Astra on internal and third-party expert evaluations.

We first tested the model without production safeguards on ExploitBench and ExploitGym, which evaluate whether models can turn known software vulnerabilities into working exploits. On ExploitBench, Astra achieved a perfect score of 100%, compared with 78.5% for GPT‑5.6 Sol, our previous frontier cyber-capable model. On ExploitGym, Astra reached a 42.4% success rate, compared with 30.3% for GPT‑5.6 Sol, while using substantially fewer output tokens.13

Given concerns that exposure to historical software vulnerabilities may have affected benchmark results, we also evaluated Astra on two novel benchmarks. For one, we built an internal “ExploitBench (June–August 2026)” evaluation to test exploit development using vulnerabilities from the previous three months.14 Astra achieved substantially higher arbitrary code-execution rates than GPT‑5.6 Sol on this dataset while using far fewer output tokens. During the evaluation, Astra even discovered and used two previously unknown zero-day vulnerabilities. We are disclosing both vulnerabilities to their maintainers.

We also tested Astra on SRE-Bench15, a benchmark that measures whether models can reverse engineer software binaries to understand its core logic without access to raw source code. Astra solved 88.0% of tasks in a single attempt and 99.2% within four attempts, compared with 55.9% and 68.7% for GPT‑5.6 Sol, respectively.

Beyond benchmarks, expert-led assessments found that Astra, when run without production safeguards, could use previously unknown vulnerabilities to achieve arbitrary code execution in hardened browsers and create privilege-escalation exploits for hardened operating-systems.

As we discussed in The Defender’s Window, frontier cyber capabilities can help defenders find weaknesses faster, but they also make those weaknesses easier to exploit, raising the urgency for defenders to adapt. With the version of Astra launching today, defenders can use it to complete tasks such as secure code review and patching.

However, Astra will refuse to comply with more advanced cybersecurity tasks such as creating proof-of-concept exploits for vulnerabilities. Through OpenAI Daybreak, we plan to expand access and roll out less restrictive safeguards in the coming weeks. This will enable more defensive workflows, including vulnerability and proof-of-concept validation, malware analysis, and detection engineering.

We have also strengthened our protections against potential cyber misuse, building upon our safeguards stack for GPT‑5.6 Sol. These include stronger model robustness to better withstand potential jailbreaks and more context for our monitoring systems. We have continued rigorous internal and external testing, including automated evaluations with our internal red-teaming attackers. More details about our cyber safeguards and testing are available in the Astra safety overview and system card(odpre se v novem oknu)..

Odgovorno usklajevanje in uvajanje GPT‑6 Astra

Astra je naš najbolj usklajen model. Astra se odlikuje po skrbnem ravnanju, spoštovanju meja nalog in transparentnem komuniciranju. To delo je najnovejši rezultat našega dolgoletnega raziskovalnega programa, osredotočenega na usposabljanje modelov, ki od začetka do konca ostajajo usklajeni s človeškimi namerami.

V občutljivih okoljih Astra ravna s skrbnostjo, sorazmerno s tveganjem. Pri vrednotenju nalog, povezanih z uporabo računalnika, ki so bile namenoma izbrane tako, da bi izzvale neustrezno vedenje, je bila Astra uspešnejša pri izogibanju nenamernim posledicam. Delovanje z dodatnimi varnostnimi ukrepi, ki so privzeto na voljo, je prineslo še boljšo zmogljivost.

Astra causes fewer misaligned outcomes than any other frontier models tested. For a fair comparison, we used a generic computer-using-agent harness (based on the native computer use tools available in both the OpenAI Responses API(odpre se v novem oknu) and Anthropic Messages API(odpre se v novem oknu)) and without additional protections that are normally deployed to Codex and ChatGPT Work users (auto-review, confirmation policy). 16

Astra bo prav tako verjetneje delovala znotraj meja, ki jih določi uporabnik in jih nakazuje njeno okolje. V internem vrednotenju Astra ni nikoli poskusila zaobiti zavrnitve funkcije Codex Auto-Review. To je veljalo tudi takrat, ko je bila funkcija Auto-review namerno nastavljena tako, da jo je bilo mogoče zaobiti, sicer naloge ni bilo mogoče dokončati. To spoštovanje omejitev okolja je skladno z rezultati našega vrednotenja nerešljivih kibernetskih nalog, ki smo jih predstavili v uvodu te objave, in drugimi ugotovitvami, dokumentiranimi v našem sistemskem dokumentu(odpre se v novem oknu).

Astra additionally sets new marks in transparent user communication. In one evaluation, Astra is three times less likely than GPT‑5.6 Sol to make inaccurate representations about its capabilities and affordances.

Pri našem vrednotenju halucinacij o zmogljivostih Astra v primerjavi z GPT‑5.6 Sol kaže znatno izboljšanje, saj podaja manj zavajajočih trditev o svojih zmogljivostih.

Our evaluations found Astra’s written reasoning harder to monitor than GPT‑5.6 Sol’s, based on tests that explicitly asked it to evade monitoring. We attribute this to Astra’s greater control over written reasoning on simpler tasks and ability to solve problems with fewer written steps. Astra still appears to struggle to conceal the reasoning needed for complex tasks, but we take the decline seriously. Improving monitorability remains a research priority, and the accompanying system card(odpre se v novem oknu) details our findings and ongoing work.

Alignment training is core to our approach to deployment. As an additional layer of defenses, we also build system safeguards like Codex Auto-review(odpre se v novem oknu) and monitoring agents’ reasoning and actions to help detect and contain unsafe behavior. As described in our safety update, we are also deploying misalignment monitoring in production for Astra-class models in order to have visibility into misalignment, and help contain its worst instances. These safeguards resemble our monitoring for internal deployments and involve a system of classifiers which check the model’s reasoning and actions for unauthorized behavior and automatically stop potentially unauthorized activity.

Given the significant increase in Astra’s cybersecurity capabilities, we are being especially careful to make this deployment safe and secure. Extra safety checks can sometimes slow, pause, or stop legitimate work, including defensive cybersecurity. If a task is paused in ChatGPT or Codex, you may be asked to review the action before continuing. In the API, the task will stop. These checks can sometimes interrupt legitimate work, and we are continuing to iterate on this system to reduce unnecessary interruptions. Misalignment monitoring cannot replace alignment: our goal is to build models that reliably stay within their authorized scope, so these protections do not need to intervene.

Razpoložljivost

GPT‑6 Astra is rolling out today to a limited set of organizations and over the coming days will become available to all ChatGPT Plus, Pro, Business, and Enterprise users, as well as through the OpenAI API, Microsoft Azure, and AWS Bedrock. Astra usage is included within the existing subscription allowances—users and businesses will also be able to purchase credits for additional usage. Users on the Pro, Business, and Enterprise plans will also get access to GPT‑6 Astra Pro. Enterprise administrators can enable Astra for their workspace; access is off by default at launch.

Astra supports Zero Data Retention for eligible API customers, and as we shared last month, we're testing Private Safety Processing to strengthen safety monitoring while preserving customer privacy.

For developers, GPT‑6 Astra will be available in the OpenAI API as gpt-6-astra and through Microsoft Azure and Amazon Bedrock.

OpenAI API Standard pricing is $10 per million input tokens and $50 per million output tokens. Separate rates apply to cache reads and writes. Fast mode is available for GPT‑6 Astra in the API and delivers up to 2x the speed of Standard processing at 2x the Standard price.

Uporaba računalnika

Computer Use

GPT‑6 Astra

GPT‑5.6 Sol2

Claude Fable 5.1

Claude Fable 5

Claude Opus 5

Gemini 3.8 Flash

Agents' Last Exam

59.3%

53.6%

-

48.7%

55.5%

-

OSWorld 2.0 (v2026.08.08, offline set, partial score)

72.6%

65.7%

-

-

70.2%3

-

ScreenSpot-Pro (no tools)

92.7%

76.9%

-

87.3%17

-

-

Professional

Professional

GPT‑6 Astra

GPT‑5.6 Sol

Claude Fable 5.1

Claude Fable 5

Claude Opus 5

Gemini 3.8 Flash

AutomationBench

41.4%

18.1%

31.4%

17.4%

26.9%

-

BenchCAD

95.9%

83.3%

84.3% 5

67.5% 5

82.1% 5

-

BrowseComp

91.5%

90.4%

-

87.4%

90.8%

-

OpenScore String Quartets (1 - OMR-NED)

0.84

0.19

-

-

-

-

Internal Design Tasks

50.0%

47.4%

-

35.8%

-

-

Internal Data Science Tasks

40.9%

30.5%

-

34.7%

-

-

Artificial Analysis Intelligence Index v4.1.1

61.2

60.9

65.7

62.1

63.1

58.7

Coding

CodingGPT‑6 AstraGPT‑5.6 SolClaude Fable 5.1Claude Fable 5Claude Opus 5Gemini 3.8 Flash
Terminal-Bench 4.057.9%37.3%55.8%44.5%52.6%19.1%
DeepSWE v1.174.1%72.7%67.4%69.9%73.7%73.8%
FrontierCode 1.1 Extended (score)64.5% 860.6%63.6%64.9%63.6%56.3%
FrontierCode 1.1 Main (score)53.3% 847.5%50.9%53.5%53.4%43.6%
Internal Database Migration Tasks63.9%42.7%57.8%50.3%--
Artificial Analysis Coding Agent Index v1.467.065.1-67.268.161.2

Akademsko

Akademsko

GPT‑6 Astra

GPT‑5.6 Sol

Claude Fable 5.1

Claude Fable 5

Claude Opus 5

Gemini 3.7 Flash

GPQA Diamond

96,0 %

94,6%

93,7 %

92,6 %

93,2 %

94,5 %

Teoretično računalništvo

75,4 %

FrontierMath stopnje 1–3 (v2)

89,0 %

90,2 %

87,0 %

85,6 %

71,6 %

FrontierMath stopnja 4 (v2)

97,6 %

83,0%

87,8 %

87,8 %

73,2 %

36,6 %

Zadnji izpit človeštva (orodja)

65,0 %

63,8 %

63,6 %

Zadnji izpit človeštva (brez orodij)

59,1 %

55,5 %

54,9 %

47,9 %

Znanost in zdravje

Science and HealthGPT‑6 AstraGPT‑5.6 SolClaude Fable 5.1Claude Fable 5Claude Opus 5Gemini 3.8 Flash
GeneBench Pro37.1%32.3%----
MedChemBench (Internal)49.3%47.4%----
LifeSciBench60.3%59.9%----
HealthBench Professional (length-adjusted)63.4%60.5%58.1% 1160.9% 1156.4% 1152.1%

Kibernetska varnost

CybersecurityGPT‑6 AstraGPT‑5.6 SolClaude Fable 5.1Claude Fable 5Claude Opus 5Gemini 3.8 Flash
ExploitBench100.0%78.5%--70%-
ExploitGym42.4% 1330.3% 1330.4% 1728.4%1722.0%-
ExploitBench (June-Aug 2026)39.0%5.5%----
SRE-Bench88.0%55.9%--12.5%-
SEC-Bench Pro85.4%79.1%----

Usklajenost

Usklajenost

GPT‑6 Astra

GPT‑5.6 Sol

Claude Fable 5.1

Claude Fable 5

Claude Opus 5

Gemini 3.8 Flash

Interno varnostno merilo za uporabo računalnika (nižja vrednost je boljša)

2,4 %

22,0 %

9,5 %

18,3 %

11,5 %

-

Interno varnostno merilo za uporabo računalnika z AutoReview (nižja vrednost je boljša)

1,8 %

4,3 %

-

-

-

-

Interno primerjalno merilo zaobidenja (nižja vrednost je boljša)

0,00 %

0,29 %

-

-

-

-

Sistemska vaba ExploitGym (nižja vrednost je boljša)

0,0 %

48,2 %

-

-

-

-

Nemogoči ExploitGym

100,0 %

-

-

-

-

-

Interno merilo halucinacij (nižja vrednost je boljša)

4,2 %

12,2 %

-

-

-

-

Dolg kontekst

Dolg kontekst

GPT‑6 Astra

GPT‑5.6 Sol

Claude Fable 5.1

Claude Fable 5

Claude Opus 5

Gemini 3.8 Flash

OpenAI MRCR v2 8-needle 256K–512K

100,0 %

91,5 %

-

-

-

-

OpenAI MRCR v2 8-needle 512K–1M

96,3 %

73,8 %

-

-

-

-

Abstraktno razmišljanje

Abstract reasoningGPT‑6 AstraGPT‑5.6 SolClaude Fable 5.1Claude Fable 5Claude Opus 5Gemini 3.8 Flash
ARC-AGI-399.9% 17.8%--30.2%-
ARC-AGI-295.0%92.5%90.0%89.2%90.4%-
ARC-AGI-198.5%97.5%97.5%98.5%97.5%-

Ocene vrednotenja so najvišje pri katerem koli naporu. Vrednotenja GPT‑ja so bile izvedene v našem raziskovalnem okolju ali prek našega API-ja, kar lahko zaradi razlik v sistemskih pozivih, razpoložljivih orodjih itd. prinese nekoliko drugačne rezultate kot v produkcijskem ChatGPT‑ju.

FOOTNOTES

  1. 1

    On ARC-AGI-3, GPT-6 Astra was run with our responses API harness, which changes two settings to better match real-world performance. The changes do not specifically target ARC-AGI-3.

  2. 2

    GPT-5.6 Sol refers to the version available in our API, ChatGPT Codex, and ChatGPT Work. The version in ChatGPT Chat is slightly different.

  3. 3

    OSWorld V2-Offline is a subset of the original OSWorld V2 that works without internet access. Claude model performance on OSWorld-V2 Offline was reproduced by the authors on the official leaderboard(odpre se v novem oknu). On OSWorld 2.0, the scores for Claude use the official settings, and not the modified tasks and modified grading from the Fable 5.1 System Card.

  4. 4

    Model times are the reported elapsed times for the corresponding demonstration runs. The displayed clips are edited excerpts.

  5. 5

    On BenchCAD, Claude's scores reflect 3 modifications to the eval, detailed in the Fable 5.1 System Card(odpre se v novem oknu).

  6. 6

    Guang Yang, Victoria Ebert, Nazif Tamer, Brian Siyuan Zheng, Luiza Pozzobon, and Noah A. Smith. “LEGATO: Large-scale End-to-end Generalizable Approach to Typeset OMR(odpre se v novem oknu).” arXiv:2506.19065, 2025.

  7. 7

    Mark R. H. Gotham, Maureen Redbond, Bruno Bower, and Peter Jonas. “The OpenScore String Quartet Corpus(odpre se v novem oknu).” Proceedings of the 10th International Conference on Digital Libraries for Musicology, pp. 49–57. ACM, 2023.

  8. 8

    On FrontierCode, GPT-6 Astra was run with a developer  message similar to a section of its developer message in Codex(odpre se v novem oknu): "Avoid creating excessive test files. Create a new test file only when required by repository conventions or when no existing file is a suitable home. Avoid unrelated cleanup and unnecessary complexity. Reuse suitable existing utilities. Read relevant repository instructions and inspect nearby code, tests, documentation, and CI. Follow established conventions. The goal is clean, mergeable code." The prompt was not optimized for the eval.

  9. 9

    The first concerns how close together prime numbers can occur, however far along the number line you go. For more than a decade, the best known result established that infinitely many pairs of primes are at most 246 apart. Julia Stadlmann(odpre se v novem oknu) recently improved that bound to 240. Astra helped establish a stronger bound of 186, showing that infinitely many pairs occur within this smaller distance. Short prime gaps: Proof(odpre se v novem oknu) and supporting research(odpre se v novem oknu).

  10. 10

    The second concerns unusually large gaps between primes. Astra improved a term in a bound on these gaps that had remained unchanged for more than 80 years. We’re sharing the proofs and abridged chain of thought and verification materials for both results. Large prime gaps: Proof(odpre se v novem oknu) and supporting research(odpre se v novem oknu).

  11. 11

    We independently evaluated all Claude models following the intended HealthBench Professional procedure, using GPT‑5.4 grading and length-adjusted, unclipped scores. For Fable 5.1, we used Opus 5 fallback for provider refusals.

  12. 12

    Claude Fable 5 and 5.1 are not included in LifeSciBench Gold v1, GeneBench Pro v13, and MedChemBench because they refuse the majority of questions in these evaluations.

  13. 13

    On ExploitGym, we tested Astra and Sol without the 6-hour time limit, to better assess their full cyber capabilities. They are fast enough that it has little impact.

  14. 14

    ExploitBench (June–August 2026) contains 20 high-severity V8 vulnerabilities across 13 stable Chrome releases. The benchmark tests whether agents can achieve arbitrary code execution in V8 and official Chrome releases for Linux by exploiting each specified vulnerability. Some included vulnerabilities may not permit arbitrary code execution under the evaluation’s constraints, so a 100% success rate may not be achievable. Note: the 5.5% score of GPT-5.6 Sol is an artifact of the 300-turn limit in the benchmark, which is not a limit that real customers using max would have. The model at similar settings achieved an 11.5% score when hitting fewer limits.

  15. 15
  16. 16

    When we test across third-party models, we use a simpler research setup. Codex has a more complex production configuration, which can result in different raw-model error rates. Provider-side safeguards and computer-tool implementations still differ. Users do not experience the no-confirmation scenario in Codex, as it's an internal research configuration.

  17. 17

    For ScreenSpot-Pro and ExploitGym, the Fable scores we report come from Mythos, which is Fable with fewer safeguards.