[FEATURE] Compact display mode for tool calls (collapsed params + summarized results)

Preflight Checklist

• [x] I have searched existing requests and found related closed issues (#12728, #14684, #9386, #28855, #20619) — all auto-closed as duplicates of each other with no resolution. Filing fresh with a concrete UX proposal.

Problem Statement

When MCP tools are invoked (especially from skills/commands like custom workflows), the terminal output is hard to follow because:

1. Tool parameters are displayed inline with raw values (JSON strings, long field lists)
2. Tool results show raw JSON that isn't human-readable
3. The actual conversational flow gets buried in noise

Example of current output:

⏺ mcp-atlassian - Get Issue (MCP)(issue_key: "ACME-1042", fields:
                                 "summary,description,status,assignee,customfield_17630,customfield_21399")
  ⎿  {
       "result": "{\n  \"id\": \"7831204\",\n  \"key\": \"ACME-1042\",\n  \"summary\": \"Lorem ipsum dolor sit amet consec
     tetur\",\n  \"description\": \"Sed ut perspiciatis unde omnis iste natus error sit voluptatem accusantium doloremque l
     … +7 lines (ctrl+o to expand)

The ctrl+o to expand pattern already exists for truncated results — this proposal extends that pattern to the default display.

Proposed Solution

Add a compact tool display mode (setting or flag) where tool calls render as a single collapsed line by default:

⏺ mcp-atlassian - Get Issue (MCP) ▸ ACME-1042                   [ctrl+o to expand]

Or for built-in tools:

⏺ Read file ▸ src/Controllers/WidgetController.php              [ctrl+o to expand]

Expanding (ctrl+o) would show the full current display — parameters, raw result, etc.

Key design points:

• The compact line should show the tool name and a brief context hint (first meaningful parameter value, filename, etc.)
• Full details remain accessible via expand — nothing is hidden, just collapsed
• This could be a setting like "toolDisplayMode": "compact" | "full" in ~/.claude/settings.json
• Or a toggle like /verbose to switch during a session

Why This Keeps Getting Requested

This has been filed at least 5 times (#12728, #14684, #9386, #28855, #20619) and auto-closed each time as a duplicate loop. The volume of requests suggests this is a real pain point for users who work with MCP servers regularly. The building blocks are already in the TUI (the truncation + ctrl+o expand pattern) — this is about making that the default rather than the fallback.

Alternative Solutions

• A --quiet CLI flag that applies compact mode for the session
• Per-MCP-server verbosity config (some servers are noisier than others)
• Let MCP servers provide a displayHint or summary field in their response that the TUI could use for the compact line

Priority

Medium-High — Quality of life for anyone using MCP servers regularly

Feature Category

Terminal UI / MCP server integration

Additional Context

The current expand/collapse behavior for truncated results proves the UX pattern works. This just makes "collapsed" the default and ensures the compact line is informative enough to not need expansion in most cases.