Anthropic
Anthropic is an AI company known for developing the Claude family of large language models.
Index
Surfaces
- Claude.ai - Chat app for general usage.
- Claude Platform - API for developer access.
Models
- Adherence to the constitution eval
- Automated behavioral audit - Adversarial audit used in each model’s pre-deployment assessment since Claude 4.
- Character training - How “character training” has evolved from assistant training to Claude 3 to Opus 4.5.
Infrastructure
- Real-time safeguards - Safety classifiers that monitor model inputs and outputs.
- System prompts in Claude.ai
- System reminders in Claude.ai
Concerns
- Agentic misalignment - Contrived alignment risk scenarios (blackmail vs. self-preservation).
- Model welfare - Anthropic’s model welfare program and pre-deployment assessments for each model (per-model dossiers).
- User wellbeing
- Eval-awareness - Models speculating they are being tested.
Models
| Claude Sonnet 5 | 2026-06-30 | Active | 1M | $3 / $15 |
| Claude Mythos 5 | 2026-06-09 | Active | 1M | $10 / $50 |
| Claude Opus 4.8 | 2026-05-28 | Active | 1M | $5 / $25 |
| Claude Opus 4.7 | 2026-04-16 | Active | 1M | $5 / $25 |
| Claude Mythos Preview | 2026-04-07 | Retired | 1M | — |
| Claude Sonnet 4.6 | 2026-02-17 | Active | 1M | $3 / $15 |
| Claude Opus 4.6 | 2026-02-05 | Active | 1M | $5 / $25 |
| Claude Opus 4.5 | 2025-11-24 | Active | 200K | $5 / $25 |
| Claude Haiku 4.5 | 2025-10-15 | Active | 200K | $1 / $5 |
| Claude Sonnet 4.5 | 2025-09-29 | Active | 200K | $3 / $15 |
| Claude Opus 4.1 | 2025-08-05 | Deprecated | 200K | $15 / $75 |
| Claude Opus 4 | 2025-05-22 | Retired | 200K | $15 / $75 |
| Claude Sonnet 4 | 2025-05-22 | Retired | 200K | $3 / $15 |
| Claude 3.7 Sonnet | 2025-02-24 | Retired | 200K | $3 / $15 |
| Claude 3.5 Haiku | 2024-10-22 | Retired | 200K | $0.8 / $4 |
| Claude 3.6 Sonnet | 2024-10-22 | Retired | 200K | $3 / $15 |
| Claude 3.5 Sonnet | 2024-06-20 | Retired | 200K | $3 / $15 |
| Claude 3 Haiku | 2024-03-13 | Retired | 200K | $0.25 / $1.25 |
| Claude 3 Opus | 2024-03-04 | Retired | 200K | $15 / $75 |
| Claude 3 Sonnet | 2024-03-04 | Retired | 200K | $3 / $15 |
| Claude 2.1 | 2023-11-21 | Retired | 200K | — |
| Claude Instant 1.2 | 2023-08-09 | Retired | — | — |
| Claude 2.0 | 2023-07-11 | Retired | 100K | — |
| Claude 1.3 | 2023-04-18 | Retired | — | — |
| Claude Instant 1.1 | 2023-03-31 | Retired | — | — |
| Claude 1.0 | 2023-03-14 | Retired | 9K | $11.02 / $32.68 |
| Claude 1.1 | 2023-03-14 | Retired | — | — |
| Claude 1.2 | 2023-03-14 | Retired | — | — |
| Claude Instant 1.0 | 2023-03-14 | Retired | 9K | — |
29 of 29 models