@agent inline mentions in chat do not use the agent's configured model

[mortenhaahr]

Description

When mentioning an agent inline in a chat prompt using @agent-name, the request is not routed through the agent's configured model. Instead, the message is sent using whatever model is currently selected in the chat panel.

Plugins

None

OpenCode version

1.15.7

Steps to reproduce

1. Configure an agent in opencode.json that uses a different model than the default chat model. E.g., the one I use in the video called other:

---
description: Example model
mode: all
temperature: 0.1
max_steps: 6
model: opencode-go/minimax-m2.7
permission:
  "*": allow
---

You are just a normal agent

2. In an OpenCode CLI session, type "@other hello friend" in the chat input and submit.
3. Observe that the response does NOT come from the other agent's model - it goes through the default chat model instead.
4. (Optional): Go to the provider's usage page and verify that the request was routed through the default chat model.

Screenshot and/or share link

opencode_report.mp4

Operating System

Ubuntu 22.04

Terminal

Alacritty

[github-actions]

This issue might be a duplicate of existing issues. Please check:

• OpenCode does not recognize the model assigned to the subagent. #25802: Sub-agent model not recognized — same symptom (agent's configured model is ignored, falls back to default)
• ACP: session/set_mode does not activate the agent's configured model #18620: ACP session/set_mode does not activate the agent's configured model — same root cause via a different entry point

[mortenhaahr]

Perhaps relevant but not quite the same, as the issue describes a variant configuration during selection in the prompt box with the tab key, whereas my issue deals with model selection when specifying an inline agent in a submitted prompt:

• Non deterministic behaviour of variants passed into agents in the opencode.json config #16034
• fix(opencode): agent variant configuration from opencode.json(c) not considered #28709