SKILL.md
Automating Messages (JXA-first with UI/DB fallbacks)
Contents
- [Permissions and scope](#permissions-and-scope)
- [Default workflow](#default-workflow-happy-path)
- [Quick recipe](#quick-recipe-defensive-send)
- [Attachments and UI fallback](#attachments-and-ui-fallback)
- [Data access and forensics](#data-access-and-forensics)
- [Validation Checklist](#validation-checklist)
- [When Not to Use](#when-not-to-use)
- [What to load](#what-to-load)
Permissions and scope
- Grants needed: Automation + Accessibility; Full Disk Access for any
chat.db reads.
- Keep automation scoped and auditable; avoid unsolicited sends and DB writes.
- Pairs with
automating-mac-apps for common setup (permissions, osascript invocation, UI scripting basics).
Default workflow (happy path)
- [ ] Resolve transport: pick
serviceType (iMessage or SMS) before targeting a buddy.
- [ ] Identify recipient: filter buddies by
handle (phone/email). Avoid ambiguous names.
- [ ] Send via app-level
send: pass Buddy object to Messages.send().
- [ ] Verify window context: activate Messages when mixing with UI steps.
- [ ] Fallbacks: if send/attachments fail, use UI scripting; for history, use SQL.
Quick recipe (defensive send)
const Messages = Application('Messages');
Messages.includeStandardAdditions = true;
function safeSend(text, handle, svcType = 'iMessage') {
const svc = Messages.services.whose({ serviceType: svcType })[0];
if (!svc) throw new Error(`Service ${svcType} missing`);
const buddy = svc.buddies.whose({ handle })[0];
if (!buddy) throw new Error(`Buddy ${handle} missing on ${svcType}`);
Messages.send(text, { to: buddy });
}
- Wrap with
try/catch and log; add small delays when activating UI.
- For groups, target an existing chat by GUID or fall back to UI scripting; array sends are unreliable.
Attachments and UI fallback
- Messages lacks a stable JXA attachment API; use clipboard + System Events paste/send.
- Ensure Accessibility permission, bring app forward, paste file, press Enter.
- See
references/ui-scripting-attachments.md for the full flow and ObjC pasteboard snippet.
Data access and forensics
Reading messages limitation: The AppleScript/JXA API for Messages is effectively write-only. While send() works reliably, reading messages via chat.messages() or similar methods is broken/unsupported in modern macOS. The only reliable way to read message history is via direct SQLite access to ~/Library/Messages/chat.db.
Security consideration: Reading chat.db requires Full Disk Access permission, which grants broad filesystem access beyond just Messages. This is a significant security trade-off - granting Full Disk Access to scripts or applications exposes all user data. Consider whether reading message history is truly necessary before enabling this permission.
- Use SQL against
chat.db for history; JXA chat.messages() is unreliable/non-functional.
- Requires: System Settings > Privacy & Security > Full Disk Access for your terminal/script.
- Remember Cocoa epoch conversion (nanoseconds since 2001-01-01); use
sqlite3 -json for structured results.
- See
references/database-forensics.md for schema notes, typedstream handling, and export tooling.
Example read query (requires Full Disk Access):
sqlite3 ~/Library/Messages/chat.db "SELECT
CASE WHEN m.is_from_me = 1 THEN 'Me' ELSE 'Them' END as sender,
m.text,
datetime(m.date/1000000000 + 978307200, 'unixepoch', 'localtime') as date
FROM message m
JOIN handle h ON m.handle_id = h.rowid
WHERE h.id LIKE '%PHONE_NUMBER%'
ORDER BY m.date DESC LIMIT 10;"
Bots and monitoring
- Implement polling daemons with
launchd now that on-receive handlers are gone.
- Track
rowid, query diffs, dispatch actions, and persist state.
- See
references/monitoring-daemons.md for the polling pattern and plist notes.
Validation Checklist
When Not to Use
- For reading message history without Full Disk Access (AppleScript/JXA cannot read messages)
- For cross-platform messaging (use platform APIs or third-party services)
- For business SMS automation (use Twilio or similar APIs)
- When iMessage/SMS features are not available on the target system
- For bulk messaging (rate limits and security restrictions apply)
- When security policy prohibits Full Disk Access grants (required for any read operations)
What to load
- Control plane and send reliability:
references/control-plane.md
- UI scripting + attachments fallback:
references/ui-scripting-attachments.md
- SQL/history access:
references/database-forensics.md
- Polling bots/launchd:
references/monitoring-daemons.md