# Briefings by knowledge cutoff
Pick the file for the model's cutoff month (or the nearest earlier one). "-short" versions fit in any context window.

> **Heads-up for humans:** with internet access turned off, models often refuse to believe post-cutoff news. They call it "speculative fiction" or a "prompt injection". In our test, Gemini 3.1 Pro rejected this dataset in every offline run without a date, and believed it as soon as Google Search was on. For best results, give the model web search, today's date in the system prompt, and this briefing. Evidence: ../experiment-001-belief-test.md

- 2026-06: [short](cutoff-2026-06-short.md) · [full](cutoff-2026-06.md) — Claude Sonnet 5.5, Claude Opus 5.5, Claude Fable 5.1, Claude Mythos 5.1
- 2026-05: [short](cutoff-2026-05-short.md) · [full](cutoff-2026-05.md) — Claude Opus 5, GPT-6 Luna, Grok 4.7
- 2026-04: [short](cutoff-2026-04-short.md) · [full](cutoff-2026-04.md) — GPT-6 Sol, GPT-6 Astra
- 2026-03: [short](cutoff-2026-03-short.md) · [full](cutoff-2026-03.md) — Gemini 3.8 Flash
- 2026-02: [short](cutoff-2026-02-short.md) · [full](cutoff-2026-02.md) — GPT-5.6 Terra, GPT-5.6 Luna, GPT-5.6 Sol
- 2026-01: [short](cutoff-2026-01-short.md) · [full](cutoff-2026-01.md) — Claude Sonnet 5, Claude Fable 5, Claude Opus 4.8, Claude Opus 4.7, Muse Glimmer 30B
- 2025-12: [short](cutoff-2025-12-short.md) · [full](cutoff-2025-12.md) — GPT-5.5 Pro, GPT-5.5
- 2025-10: [short](cutoff-2025-10-short.md) · [full](cutoff-2025-10.md) — Amazon Nova 2 Lite
- 2025-09: [short](cutoff-2025-09-short.md) · [full](cutoff-2025-09.md) — NVIDIA Nemotron 3.5 Lightning (30B-A3B), NVIDIA Nemotron 3 Ultra (550B-A55B)
- 2025-08: [short](cutoff-2025-08-short.md) · [full](cutoff-2025-08.md) — Claude Sonnet 4.6, GPT-5.3-Codex, GPT-5.4
- 2025-07: [short](cutoff-2025-07-short.md) · [full](cutoff-2025-07.md) — GPT-Live 1
- 2025-06: [short](cutoff-2025-06-short.md) · [full](cutoff-2025-06.md) — NVIDIA Nemotron 3 Super (120B-A12B)
- 2025-05: [short](cutoff-2025-05-short.md) · [full](cutoff-2025-05.md) — Claude Opus 4.6, Claude Opus 4.5
- 2025-02: [short](cutoff-2025-02-short.md) · [full](cutoff-2025-02.md) — Claude Haiku 4.5
- 2025-01: [short](cutoff-2025-01-short.md) · [full](cutoff-2025-01.md) — Claude Sonnet 4.5, Gemini 2.5 Flash, Gemini 2.5 Pro
- 2024-10: [short](cutoff-2024-10-short.md) · [full](cutoff-2024-10.md)
- 2024-09: [short](cutoff-2024-09-short.md) · [full](cutoff-2024-09.md) — GPT-Realtime-2.1, GPT-Realtime-2, GPT-Audio-1.5 (and gpt-audio / gpt-audio-mini), GPT-Realtime-1.5
- 2024-08: [short](cutoff-2024-08-short.md) · [full](cutoff-2024-08.md) — Llama 4 Maverick (17B-128E), Llama 4 Scout (17B-16E)
- 2024-06: [short](cutoff-2024-06-short.md) · [full](cutoff-2024-06.md) — gpt-oss-120b, gpt-oss-20b, GPT-4.1
- 2023-10: [short](cutoff-2023-10-short.md) · [full](cutoff-2023-10.md) — GPT-4o