feat(cli): add /perf performance monitoring dashboard

[1nonlyasta]

Summary

Add an in-CLI performance monitoring dashboard accessible via /perf command.

What's included:

• /perf — overview dashboard (timing, memory, session stats)
• /perf memory — detailed heap/RSS breakdown with utilization bars
• /perf tools — per-tool execution table (calls, avg latency, success rate)
• /perf api — per-model API latency and token usage
• /perf export — JSON performance report

Files changed:

• New: perfCommand.ts — slash command with 5 subcommands
• New: PerfDisplay.tsx — Ink dashboard component with 4 view panels
• Modified: types.ts — added PerfSnapshot, PERF_DASHBOARD MessageType
• Modified: HistoryItemDisplay.tsx — wired PerfDisplay rendering
• Modified: BuiltinCommandLoader.ts — registered /perf command

Context

This aligns with GSoC 2026 Project Idea #5: Performance Monitoring and Optimization Dashboard.

Relates to #21142
Relates to #22403

[gemini-code-assist]

Summary of Changes

Hello, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request introduces a new performance monitoring dashboard accessible through the /perf command in the CLI. This feature provides users with detailed insights into various aspects of the application's performance, including session duration, memory usage, tool execution times, and API latency. By offering a comprehensive view of these metrics, the dashboard aims to empower users to identify bottlenecks and optimize their CLI experience, aligning with the goal of improving overall application efficiency.

Highlights

• New /perf Command: Introduced a new CLI command /perf with subcommands (overview, memory, tools, api, export) for comprehensive performance monitoring.
• Interactive Performance Dashboard: Added PerfDisplay.tsx, an Ink-based React component, to visualize performance metrics in an interactive dashboard within the CLI.
• Performance Data Structures: Defined new TypeScript types (PerfSnapshot, HistoryItemPerfDashboard, PERF_DASHBOARD MessageType) to structure and manage performance-related data.
• UI Integration: Integrated the PerfDisplay component into HistoryItemDisplay.tsx to enable rendering of the performance dashboard within the CLI's history view.
• Command Registration: Registered the new perfCommand within BuiltinCommandLoader.ts to make it available for use in the CLI.

Changelog

• packages/cli/src/services/BuiltinCommandLoader.ts
  • Imported perfCommand.
  • Registered perfCommand in the list of built-in commands.
• packages/cli/src/ui/commands/perfCommand.ts
  • Added a new file defining the perfCommand slash command.
  • Implemented collectPerfSnapshot function to gather session performance metrics.
  • Defined subcommands for overview, memory, tools, api, and export of performance data.
• packages/cli/src/ui/components/HistoryItemDisplay.tsx
  • Imported PerfDisplay component.
  • Added conditional rendering for PerfDisplay when itemForDisplay.type is perf_dashboard.
• packages/cli/src/ui/components/PerfDisplay.tsx
  • Added a new file defining the PerfDisplay React component.
  • Implemented StatRow, SubStatRow, Section, and ProgressBar reusable components.
  • Created OverviewPanel, MemorySummaryPanel, MemoryDetailPanel, ToolsPerfPanel, and ApiPerfPanel for different dashboard views.
  • Included helper functions for formatting and coloring performance metrics.
• packages/cli/src/ui/types.ts
  • Defined the PerfSnapshot interface to structure collected performance data.
  • Defined HistoryItemPerfDashboard type for displaying performance dashboard items in history.
  • Added PERF_DASHBOARD to the MessageType enum.
  • Included HistoryItemPerfDashboard in the HistoryItemWithoutId union type.

Activity

• The author, 1nonlyasta, initiated this pull request to add a performance monitoring dashboard.
• The PR description clearly outlines the purpose, the various subcommands available, and the specific files modified or added.
• The work is explicitly linked to GSoC 2026 Project Idea Configure linter + prettier. #5 and relates to existing issues feat(cli): add /stats perf subcommand for memory and startup timing display #21142 and Feature: Add performance monitoring dashboard command (/perf) #22403, indicating a planned and contextualized feature addition.

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[gemini-code-assist]

Code Review

This pull request introduces a valuable performance monitoring dashboard accessible via the /perf command. The implementation is well-structured, with new components for displaying performance metrics and a new command to gather and present the data.

My review includes two main points for improvement, both in packages/cli/src/ui/commands/perfCommand.ts:

1. Refactoring duplicated logic in the command actions to improve maintainability.
2. Optimizing data aggregation to be more efficient by reducing redundant loops.

These changes will make the new feature more robust and easier to maintain in the future. Overall, this is a great addition to the CLI.

[gemini-cli]

Hi there! Thank you for your interest in contributing to Gemini CLI.

To ensure we maintain high code quality and focus on our prioritized roadmap, we have updated our contribution policy (see Discussion #17383).

We only guarantee review and consideration of pull requests for issues that are explicitly labeled as 'help wanted'. All other community pull requests are subject to closure after 14 days if they do not align with our current focus areas. For this reason, we strongly recommend that contributors only submit pull requests against issues explicitly labeled as 'help-wanted'.

This pull request is being closed as it has been open for 14 days without a 'help wanted' designation. We encourage you to find and contribute to existing 'help wanted' issues in our backlog! Thank you for your understanding and for being part of our community!

[cocosheng-g]

@1nonlyasta, apologies for the bot closing this PR! We have reopened it. Please sync your branch to the latest main and we will have someone review it shortly.

[cocosheng-g]

Closing this PR as we have re-evaluated the feature request (#22483). Because it touches core telemetry and API usage statistics, it requires internal maintainer alignment and is not currently open for community contribution. Thank you for your efforts and understanding!