Parent LLM ignores subagent isolation when using `@agent` references

[joshuadavidthomas]

Description

When using @agent references (e.g., @oracle) multiple times in a session, the parent LLM sends prompts assuming the subagent remembers previous calls - "continue your analysis", "refine what you said earlier". Each @agent triggers the Task tool, which creates an isolated session. The parent LLM doesn't internalize this.

task.txt:21 says "Each agent invocation is stateless..." but this doesn't register. I've seen the parent LLM send follow-up prompts with "Updated Context" and "as previously thought" - phrases that only make sense if the subagent saw the prior request.

Might be minor - the subagent usually figures it out from context, but it sometimes causes confusion.

Suggested fix

Make the instruction more prominent in task.txt:

IMPORTANT: Each @agent call creates a NEW session with NO memory. Do NOT reference "previous analysis" or assume continuity - include ALL context every time.

OpenCode version

1.0.152

Steps to reproduce

1. Start a session and ask the LLM to analyze something complex
2. Use @agent to call a subagent
3. Ask a follow-up that requires calling the same agent again
4. Observe the parent LLM sending a prompt like "Updated Context" or referencing what the subagent "previously" found

Screenshot and/or share link

https://opncd.ai/share/1igWcU6U

Operating System

Linux

Terminal

Ghostty

[github-actions[bot]]

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

• #2390: Switching to a child session doesn't send subsequent messages to that session but to the parent one - describes the parent LLM continuing to interact with the parent session instead of the subagent
• #4483: Subagents inappropriately inherit main agent instructions from CLAUDE.md/AGENTS.md - describes context pollution between parent and subagents
• #4422: Primary agent responds in subagent view; delegated subagent views become inaccessible - related issue with parent/subagent context confusion

Feel free to ignore if none of these address your specific case.

[joshuadavidthomas]

Not a duplicate. Those issues are about UI routing (#2390, #4422) or config inheritance (#4483). This is about the parent LLM's understanding of subagent isolation - it generates prompts assuming continuity ("Updated Context", "as previously thought") when each subagent call is stateless.

[rekram1-node]

There is this part here so they aren't stateless in this case, perhaps we should reword it:

unless you provide a session_id.

[joshuadavidthomas]

There is this part here so they aren't stateless in this case, perhaps we should reword it:

unless you provide a session_id.

Yeah, I'm totally oblivious on the "art" of prompting given how fast things are changing these days -- but I would assume some **bold** or UPPERCASE callouts might help? I don't mind opening a PR to get the ball rolling, assuming there's interest in pursuing some sort of tweak to the wording.

[rekram1-node]

I guess some helpful info:

what model were u using?

can you share anything about your oracle agent?

can you share the session where this happened?

[joshuadavidthomas]

Sure! I was using a mixture of Sonnet 4.5 and Opus 4.5 -- though I think primarily Opus was the one calling the subagent.

The oracle agent basically straight lifted from the Amp Code agent of the same name. I found a prompt here and also saw a version of it in the Oh My OpenCode codebase. I used GPT-5.2 as the model for the subagent oracle.

I shared the session in my initial description, but for some reason the page is blank when I try to load it:

Screenshot and/or share link

opncd.ai/share/1igWcU6U

Looking in the console I see logs that show the actual chat.

---

After having a sleep on it, I think I'm just going to do some tinkering with overriding the task tool with a custom tool and see if anything comes from that. I'll go ahead and close this to reduce the issue noise in the repo. Thanks for taking the time to reply!