CLI AI: Add --json flag for headless NDJSON output

[wesleyfantinel]

Related issues

• Related to sandboxed/Docker deployment of Studio AI agent

How AI was used in this PR

Claude was used to brainstorm the design, write the implementation plan, and implement the changes. All code was reviewed and validated by the author.

Proposed Changes

• Add --json flag and positional message argument to studio ai command for headless mode
• Introduce AiOutputAdapter interface with two implementations:
  • InteractiveAdapter — wraps existing AiChatUI (zero changes to TUI code)
  • JsonAdapter — streams typed NDJSON events to stdout
• Add autoApprove option to AiAgentConfig — in JSON mode, all tool permissions are auto-approved (sandbox is trusted)
• In JSON mode, agent questions are emitted as question.asked events and the process exits (service resumes via session)
• Define NDJSON event schema: message, progress, info, error, question.asked, turn.started, turn.completed
• Add 4 new tests for JSON mode (single turn, SDK message streaming, error handling, autoApprove flag)

Usage

# Single turn, streams NDJSON events to stdout
studio ai "create a theme for my site" --json

# Validation: --json requires a message
studio ai --json  # Error: --json requires an initial message argument

Files changed

File	Change
apps/cli/ai/json-events.ts (new)	NDJSON event types and emitEvent() helper
apps/cli/ai/output-adapter.ts (new)	AiOutputAdapter interface, InteractiveAdapter, JsonAdapter
apps/cli/ai/agent.ts	Add autoApprove field to AiAgentConfig, short-circuit canUseTool
apps/cli/commands/ai/index.ts	Positional message, --json flag, adapter pattern, single-turn path
apps/cli/commands/ai/sessions/resume.ts	Pass InteractiveAdapter to updated runCommand signature
apps/cli/commands/ai/tests/ai.test.ts	4 new JSON mode tests

Testing Instructions

1. Build the CLI: npm run cli:build
2. Run in JSON mode:

   node apps/cli/dist/cli/main.js ai "hello, what can you do?" --json

3. Verify NDJSON events are streamed to stdout (one JSON object per line)
4. Verify turn.started is the first event and turn.completed is the last
5. Run in interactive mode (no --json flag) and verify the TUI works as before:

   node apps/cli/dist/cli/main.js ai

6. Verify --json without a message shows an error:

   node apps/cli/dist/cli/main.js ai --json

7. Run tests: npm test -- apps/cli/commands/ai/tests/ai.test.ts

Pre-merge Checklist

• Have you checked for TypeScript, React or other console errors?

[draganescu]

Edited