Feature Request: DisplayStructuredOutput Tool (Inverse of AskUserQuestion)

[alexeyv]

Feature Request: DisplayStructuredOutput Tool (Inverse of AskUserQuestion)

Summary

Add a tool that allows Claude to send hierarchical, expandable structured data to the terminal — enabling users to drill down into details without additional LLM round-trips.

The Problem

Currently, when Claude needs to present information with varying levels of detail:

1. Wall of text — Everything shown at once, eyes glaze over
2. Summary only — User asks follow-up, burns tokens + latency
3. No middle ground — Can't show summary with accessible drill-downs

Terminal constraints (no columns, no hover, limited width) make this worse. Users either get overwhelmed or have to keep asking "show me more about X."

Proposed Solution

A DisplayStructuredOutput tool — the inverse of AskUserQuestion:

AskUserQuestion	DisplayStructuredOutput
Structured input collection	Structured output presentation
Options, multi-select, headers	Tables, columns, collapsibles
Terminal renders nicely	Terminal renders adaptively

Example usage:

type: hierarchical
title: "Sprint Status"
sections:
  - header: "Epics"
    summary: "1 in-progress, 2 backlog"
    expandable: true
    content:
      - "epic-1: in-progress (4 stories)"
      - "epic-2: backlog (3 stories)"
  - header: "Stories" 
    summary: "2 active, 4 pending"
    expandable: true
    content:
      type: table
      headers: [Story, Status, Epic]
      rows:
        - [1-2-login, in-progress, epic-1]
        - [1-3-settings, review, epic-1]
  - header: "Next Action"
    emphasis: high
    content: "Run `dev-story` for 1-2-login"

Rendered in terminal:

📊 Sprint Status
├─ Epics: 1 in-progress, 2 backlog      [+]
├─ Stories: 2 active, 4 pending         [+]
└─ Next Action: Run `dev-story` for 1-2-login

User clicks [+] → instant local expansion, no LLM call.

Key Benefits

1. Zero tokens for exploration — Data pre-fetched, expansion is client-side
2. Instant response — No round-trip latency for drill-downs
3. User controls depth — Scan summary, expand what's interesting
4. Better terminal UX — Avoids wall-of-text, uses horizontal space intelligently
5. Graceful degradation — Falls back to plain text in dumb terminals

Primitives Needed

• table — Headers + rows, auto-column-width based on terminal
• columns — Side-by-side layout when width permits, stacked when narrow
• collapsible — Summary visible, content on click/keypress
• cards — Titled blocks with emphasis levels
• list — Grouped items with optional nesting

Prior Art

• AskUserQuestion already proves structured terminal I/O works
• TodoWrite sends structured data (per #8723) — display side could be richer
• ctrl+o expansion for bash output (#10636) — same concept, limited scope

Use Cases

• Sprint/project status dashboards
• Code review summaries with expandable file details
• Search results with preview + full content
• Error reports with stack traces collapsed by default
• Any "summary + details on demand" pattern