No longer listed in Cursor's docs, so mainly historical now that Composer 2.5 is current.
Kenning's take
What it does
Composer 1.5 took the same base model as Composer 1 and scaled reinforcement learning about 20 times further. It thinks briefly on easy problems and longer on hard ones, and can summarise its own work to keep going when it runs out of context. It has since been replaced by Composer 2 and 2.5.
- Reinforcement learning scaled 20x beyond Composer 1
- Thinking model that adjusts effort to task difficulty
- Self-summarisation for long tasks
- Same pretrained base as Composer 1
Who it suits. Developers using Cursor who want a fast in-house coding model for agent work.
Key facts
- Category
- AI models
- Part of
- Cursor
- Made by
- Anysphere, Inc. (Cursor)
- Released
- 9 February 2026
- How to get it
- Released inside Cursor; No longer listed in Cursor's models and pricing docs as of 2026-10-11; Composer 2.5 is the current version
- Works on
- Cursor (desktop, web, CLI, iOS)
- In the UK
- Yes
FAQ
When was Composer 1.5 released?
Cursor released Composer 1.5 on 9 February 2026.
Is Composer 1.5 still available?
It is no longer listed in Cursor's models and pricing docs. Composer 2.5 is the current version.
Facts from the maker's own pages and the sources listed. Checked 2026-10-11.
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Cursor Composer 2
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Cursor Composer 2.5
Current Cursor in-house coding model, tuned for long agent sessions and more reliable behaviour
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