Permission Resolution (State-Based)

This document explains how permission mode is resolved for session messages, depending on current state in the app and CLI.

Scope

• App-side state resolution (session defaults, persisted values, outbound message metadata)
• Claude CLI resolution (startup mode, per-message updates, sandbox policy)
• Final mode sent to Claude SDK

Permission Modes

• Shared mode type: default | acceptEdits | bypassPermissions | plan | read-only | safe-yolo | yolo
• Claude SDK supports: default | acceptEdits | bypassPermissions | plan
• Mapping to Claude happens in packages/happy-cli/src/claude/utils/permissionMode.ts:
  • yolo -> bypassPermissions
  • safe-yolo -> default
  • read-only -> default

App-Side Resolution

1) Session state load/merge

packages/happy-app/sources/sync/storage.ts

When sessions are merged, the app resolves session.permissionMode using this order:

1. Existing in-memory session mode (if non-default)
2. Persisted per-session mode from local storage (if non-default)
3. Mode from server session payload (if non-default)
4. Sandbox fallback:
   • If session.metadata.sandbox.enabled === true: bypassPermissions
   • Otherwise: default

2) New-session draft fallback

packages/happy-app/sources/sync/persistence.ts

If draft permission mode is missing:

• Draft default: default

3) New session UI defaults

packages/happy-app/sources/app/(app)/new/index.tsx packages/happy-app/sources/components/NewSessionWizard.tsx

Default selection:

• default

If selected mode is invalid for the currently selected agent, UI resets to agent default above.

4) Outbound message mode

packages/happy-app/sources/sync/sync.ts

On send:

• If session.permissionMode is non-default, send it.
• Otherwise:
  • If session.metadata.sandbox.enabled === true: send bypassPermissions
  • Else send default

This value is sent in:

• encrypted message meta.permissionMode
• socket envelope permissionMode

Claude CLI Resolution

1) Startup resolution

packages/happy-cli/src/claude/runClaude.ts packages/happy-cli/src/claude/utils/permissionMode.ts

Initial mode comes from:

1. --dangerously-skip-permissions (highest priority) -> bypassPermissions
2. --permission-mode VALUE or --permission-mode=VALUE
3. Provided options.permissionMode

Then sandbox policy is applied:

• If sandbox enabled: force bypassPermissions
• If sandbox disabled: keep resolved mode

2) Per-message updates in remote flow

packages/happy-cli/src/claude/runClaude.ts

When a user message includes meta.permissionMode:

• If sandbox enabled: forced to bypassPermissions
• If sandbox disabled: use incoming mode

3) Local Claude process

packages/happy-cli/src/claude/claudeLocal.ts

If sandbox is enabled, launcher appends --dangerously-skip-permissions before spawn.

Effective Result Matrix

Sandbox enabled

• App fallback mode is bypassPermissions when session mode is default/missing
• Claude CLI sandbox policy still forces bypassPermissions in remote flow

Sandbox disabled

• If app/session mode is non-default: that mode is used
• If app/session mode is default or missing:
  • App sends default
  • CLI uses normal mode resolution (no sandbox forcing)

Why this is stable now

• Client fallback only forces skip-permissions for sandboxed sessions.
• CLI sandbox policy guarantees sandboxed Claude sessions cannot re-enable permission prompts via message metadata.