Composer 2 classic use fast mode on custom ACP agent with CLI in IntelliJ

Support Bug Reports
, ,
1

Where does the bug appear (feature/product)?

Cursor CLI

Describe the Bug

Model Composer 2 classic cannot be used in IntelliJ when cursor cli is added as custom acp agent. Composer 2 fast is used when choosing composer 2 and Composer 2 fast option is not available.

Steps to Reproduce

  • Install cusor cli
  • Install IntelliJ IDEA 2026.1 + AI plugin (without enabling AI)
  • add custom ACP server :
    {
    “default_mcp_settings”: {},
    “agent_servers”: {
    “Cursor Agent”: {
    “command”: “cursor-agent”,
    “args”: [
    “acp”
    ],
    “env”: {
    “CURSOR_LOG_LEVEL”: “info”
    }
    }
    }
    }
  • Choose Composer 2
  • check in usage wich model has been used

Expected Behavior

Composer 2 classic should be used and Composer 2 fast should be available

Operating System

MacOS

Version Information

Cursor Agent v2026.03.30-a5d3e17
IntelliJ IDEA v2026.1

Additional Information

I cannot add ACP cursor agent using intelliJ ACP registry because of org policy.

Does this stop you from using Cursor

No - Cursor works, but with this issue

4

Thanks for the feedback @THIBAULT! Right now, ACP supports a fixed variant for each model.

For Composer 2, that fixed variant is Fast mode. Unfortunately, there’s no workaround at the moment.

I’ll send your feedback about wanting to use Composer 2 (non-fast) in ACP to the team!

7

Understood ! Thanks for the response and for passing on my feedback to the team.

I do find it a bit confusing that the model selection doesn’t explicitly indicate when the ‘Fast mode’ variant of Composer 2 is being used.