anomalyco/opencode
1
0
Fork 0
mirror of https://github.com/anomalyco/opencode.git synced 2026-07-22 02:05:26 -04:00
Code Issues 5.9k Packages Projects Releases 19 Wiki Activity

Some models are overeager to add | head -n or | tail -n to commands #7612

New Issue
Open
opened 2026-02-16 18:07:43 -05:00 by yindo · 1 comment
yindo commented 2026-02-16 18:07:43 -05:00
Owner
Copy Link
Copy Source

Originally created by @smola on GitHub (Jan 26, 2026).

Originally assigned to: @thdxr on GitHub.

Description

Some models are overeager to add | head -n or | tail -n to commands. This makes sense with some other coding agents (e.g. gemini-cli will just fall apart on large outputs) but large outputs from Bash is handled gracefully in OpenCode, so it should not be needed.

In some cases, overeager use of head or tail leads to command repetition because the limit was too small to capture the required output. Even worse, sometimes the use of head will just make the main command file on a broken pipe.

There's a related case in overeager use of tee that could probably be addressed too, but it's practical impact in task performance is lower.

System prompt and tool call descriptions should be refined to mitigate this issue.

Plugins

None

OpenCode version

1.1.35

Steps to reproduce

No response

Screenshot and/or share link

No response

Operating System

Linux

Terminal

Ghostty

Originally created by @smola on GitHub (Jan 26, 2026). Originally assigned to: @thdxr on GitHub. ### Description Some models are overeager to add `| head -n` or `| tail -n` to commands. This makes sense with some other coding agents (e.g. `gemini-cli` will just fall apart on large outputs) but large outputs from Bash is handled gracefully in OpenCode, so it should not be needed. In some cases, overeager use of `head` or `tail` leads to command repetition because the limit was too small to capture the required output. Even worse, sometimes the use of `head` will just make the main command file on a broken pipe. There's a related case in overeager use of `tee` that could probably be addressed too, but it's practical impact in task performance is lower. System prompt and tool call descriptions should be refined to mitigate this issue. ### Plugins None ### OpenCode version 1.1.35 ### Steps to reproduce _No response_ ### Screenshot and/or share link _No response_ ### Operating System Linux ### Terminal Ghostty
yindo added the bug label 2026-02-16 18:07:43 -05:00
yindo commented 2026-02-16 18:07:43 -05:00
Author
Owner
Copy Link
Copy Source

@github-actions[bot] commented on GitHub (Jan 26, 2026):

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

  • #10438: gemini-3-pro-preview tends to avoid grep/glob due to system prompt issues affecting model behavior
  • #10640: Feature request to intercept known bash patterns (cat, head, tail, grep, find) and replace them with specialized tools
  • #10634: Compaction overflow check doesn't account for large tool outputs, which may incentivize models to limit output

These related issues discuss the root cause (system prompts and tool interception) and potential solutions to prevent models from being overeager about limiting command output.

Feel free to ignore if your case is specifically different from these.

@github-actions[bot] commented on GitHub (Jan 26, 2026): This issue might be a duplicate of existing issues. Please check: - #10438: gemini-3-pro-preview tends to avoid grep/glob due to system prompt issues affecting model behavior - #10640: Feature request to intercept known bash patterns (cat, head, tail, grep, find) and replace them with specialized tools - #10634: Compaction overflow check doesn't account for large tool outputs, which may incentivize models to limit output These related issues discuss the root cause (system prompts and tool interception) and potential solutions to prevent models from being overeager about limiting command output. Feel free to ignore if your case is specifically different from these.
Sign in to join this conversation.
No Branch/Tag Specified
Branches Tags
Labels
Clear labels
acp
bad
bug
discussion
docs
documentation
enhancement
extension
good first issue
growth
help-wanted
mcp
model-problem
needs:compliance
nix
opentui
perf
pull-request
Mirrored from GitHub Pull Request
 tui
web
windows
zen
No Label bug
Milestone
No items
No Milestone
Projects
Clear projects
No project
Assignees
Clear assignees
yindo
No Assignees
1 Participants
Notifications
Due Date
No due date set.
Dependencies

No dependencies set.

Reference: anomalyco/opencode#7612
Delete Branch "%!s()"

Deleting a branch is permanent. Although the deleted branch may continue to exist for a short time before it actually gets removed, it CANNOT be undone in most cases. Continue?