fix(cli): mapToDisplay uses unbounded JSON.stringify for ErroredToolCall description

[TravisHaa]

Bug Description

In packages/cli/src/ui/hooks/toolMapping.ts, when a tool call errors before its invocation is built, the display description falls back to the raw serialized args:

if (call.status === CoreToolCallStatus.Error) {
  description = JSON.stringify(call.request.args);
}

There is no length cap. Tools called with large payloads — write_file with a full file body, execute_code with a long script, MCP tools with structured input — produce descriptions that are hundreds of kilobytes long. This string is rendered as a single line in the tree node row, causing:

• Layout overflow in the task tree and flat tool list
• Excessive re-render cost as Ink tries to measure and wrap the string
• Potential terminal emulator slowdowns from a single massive text node

Fix

Truncate to 120 characters with an ellipsis:

const rawArgs = JSON.stringify(call.request.args);
description = rawArgs.length > 120 ? rawArgs.slice(0, 117) + '...' : rawArgs;

[gemini-cli]

👋 @student-ankitpandit, thanks for your interest in this issue! We're reserving self-assignment for issues that have been marked with the help wanted label. Feel free to check out our list of issues that need attention.

[TravisHaa]

@student-ankitpandit You were never assigned in the first place because this issue doesn't have a help-wanted label assigned to it. Please pay more attention next time.

[student-ankitpandit]

Yeah, my bad I didn't saw that earlier but now i'll put more attention before fixing one.

[cocosheng-g]

Triage Summary

This is a well-defined bug fix that ensures errored tool call descriptions are truncated in the UI state, preventing layout overflow and performance issues when tools are called with large payloads. Since it is a safe and localized UI fix that improves the community experience, it is categorized as a Help-wanted task.

@TravisHaa, apologies! It looks like your PR #22594 was incorrectly closed by our bot. I have reopened it and assigned this issue to you. Would you like to continue working on it?