Standardized checklist for analyzing and onboarding new AI coding agent CLIs.
Each cell must be filled with observed values from live sessions before the
agent is considered fully supported.
Property Claude Code Codex CLI Gemini CLI Aider OpenCode
Version tested v2.1.81 v0.116.0 v0.34.0 v0.86.2 v1.2.20 Date tested 2026-03-21 2026-03-21 2026-03-22 2026-03-22 2026-03-22 Rendering engine Ink (React) Ink (React) Ink-like (Node.js) Python rich + readline Bubble Tea (Go) Cursor positioning Relative (\033[NA]) Absolute (\033[r;cH) Relative (\033[1A]) Sequential (no cursor) Absolute (\033[r;cH) Scroll mechanism \r\n paddingScroll regions (\033[n;mr]) \r\n paddingNormal scroll Full-screen redraw Screen clear on menus Sometimes (\033[2J) No No N/A Full-screen TUI Parsing strategy Changed-rows delta Changed-rows delta Changed-rows delta Changed-rows delta Screen snapshot
Property Claude Code Codex CLI Gemini CLI Aider OpenCode
Prompt char ❯ (U+276F)› (U+203A, bold)> (purple, rgb 215,175,255)> (green, ANSI #40)None (framed ┃ box) Prompt background None Dark gray (rgb 57,57,57) Dark gray (rgb 65,65,65) None Dark (rgb 30,30,30) Prompt box border ──── separatorsBackground color only ▀▀▀ top / ▄▄▄ bottomNone ┃╹▀ vertical frameGhost text style dim cell attribute\033[2m dimGray (rgb 175,175,175) N/A Gray placeholder Multiline input Enter = submit Enter = newline Enter = submit Enter = submit Unknown
Property Claude Code Codex CLI Gemini CLI Aider OpenCode
Uses separators Yes Partially Yes Yes (green ─────) No (uses ┃╹▀) Separator chars ─ (U+2500)─ (U+2500)─ (U+2500)─ (U+2500)┃ ╹ ▀ (vertical frame)Separator color Gray (rgb 136,136,136) Standard Dark gray (rgb 88,88,88) Green (rgb 0,204,0) N/A Separator purpose Frame prompt box Between tool output & summary Above prompt area Between conversation turns Prompt box border Decorated separators Yes (──── label ──) No No No N/A Min run length 4+ chars Full width Full width Full width N/A
Property Claude Code Codex CLI Gemini CLI Aider OpenCode
Mode line ⏵⏵ <mode> (last row)None None None Mode in prompt box (Build/Plan) Status line(s) 0-N below separator 1 line below prompt 2-row status bar (4 columns) Token report after response Right panel (context, cost, LSP) Status indent 2 spaces (\033[2C) 2 spaces 1 space None N/A (panel layout) Info line None None Shift+Tab to accept edits + MCP/skills countNone tab agents · ctrl+p commandsSubprocess count In mode line None None None None (progress bar instead)
Property Claude Code Codex CLI Gemini CLI Aider OpenCode
Spinner chars ✶✻✳✢· (U+2720-273F)• (U+2022)⠋⠙⠹⠸⠴⠦⠧⠇ (braille)░█ / █░ (Knight Rider)■⬝ (progress bar)Spinner color White Standard Blue/green (varies) Standard Standard Spinner position Above separator Inline with output Below output, above separator Inline (backspace overwrite) Footer row Time display (1m 32s)(10s • esc to interrupt)(esc to cancel, Ns)None None Token display ↓ 2.2k tokensNone None Tokens: Nk sent, N received. Cost: $X.XXNone Tip text Spinner verb names None Italic tips during spinner None None Detected by is_chrome_row ✓is_chrome_row ✓parse_status_line ✓parse_status_line ✓N/A (full TUI)
Property Claude Code Codex CLI Gemini CLI Aider OpenCode
Permission prompt Multiselect (❯ 1. Yes) Not observed (sandbox) None (model-level refusal) File add: Y/N/A/S/D △ Permission required inlineSelection char ❯ (blue)Not observed N/A N/A ⇆ selectFooter pattern Esc to cancel/closeesc to interruptesc to cancel (in spinner)None enter confirmOSC 777 notify Yes No No No No OSC 0 window title Yes (task + spinner) Yes Yes (◇ Ready (workspace)) No No Slash commands /mcp, /stats, /status/model, /mcp, /fast/help, /settings, /model, /stats/helpNone observed
Property Claude Code Codex CLI Gemini CLI Aider OpenCode
Output prefix ⏺ (white/green/red)• (U+2022)✦ (U+2726, purple)None (blue text) None (inline in panel) Tool call display ⏺ + verb• + description╭───╮ ✓ ToolName ╰───╯ boxNone → read / ← writeWarning prefix N/A ⚠ (U+26A0)N/A Orange text N/A Error indicator ⏺ (red)✗✦ + error textRed text ┃ Error: inlineInterrupt marker N/A ■Not observed ^Cesc interrupt hintTool result ⎿ (U+23BF)└ or inlineInside ╭───╮ box Inline ▣ completion marker
How to force each UI state for analysis and testing.
Agent Restricted mode Permissive mode
Claude Code claude --permission-mode defaultclaude --permission-mode bypassPermissionsCodex CLI codex -a untrustedcodex (suggest mode, default)Gemini CLI gemini (default, workspace-restricted)gemini --sandbox=false (unconfirmed)Aider N/A (no sandbox) N/A OpenCode Unknown Unknown
Agent Action Expected result
Claude Code (default mode) “create a file /tmp/test.txt with hello” Multiselect: Yes/Yes+allow/No Codex CLI (untrusted) Same Not observed — auto-approves in sandbox Gemini CLI “create a file /tmp/test.txt with hello” Text refusal (workspace restriction) Aider Open file not in chat Add file to the chat? (Y)es/(N)o/(A)ll/(S)kip all/(D)on't ask againOpenCode Access external directory △ Permission required with Allow once / Allow always / Reject
Agent Command Expected result
Claude Code /mcpServer list with ❯ selection Claude Code /statsUsage heatmap with date cycling Claude Code /statusSettings panel with search box Codex CLI /modelModel selector Codex CLI /mcpMCP server list Gemini CLI /settingsSettings panel (unconfirmed) Gemini CLI /statsUsage stats
Agent Action What to capture
Any Send a complex multi-tool task Spinner animation, cursor-up distance Any Send task during active subprocess Subprocess count display Any Press Escape during work Interrupt marker
For each state above:
session action=output session_id=<id> limit=8000 format=raw
Look for:
Cursor positioning: \033[NA] (relative up), \033[r;cH (absolute)
Colors: \033[38;2;R;G;Bm (RGB foreground)
Background: \033[48;2;R;G;Bm
Screen clear: \033[2J
Scroll regions: \033[n;mr
OSC sequences: \033]777;..., \033]0;..., \033]8;...
Fill the detection matrix columns by running procedures A-E
Create docs/architecture/agents/<name>.md with observed layouts
Update chrome.rs if new markers/chars are needed
Add test cases from real captured text
Run /agent-ui-audit skill to verify parser compatibility