Cos 1.0.0

Cos 1.0.0

Cos 1.0 is the first public open-source release of the native macOS app and Cos harness.

Highlights

• One native provider-neutral harness for every supported model.
• Persistent /goal state, bounded token budgets, and context compaction.
• Direct provider streaming with model-specific reasoning effort and Fast Mode controls.
• Native SwiftUI chat, sidebar, settings, work traces, True Dark mode, and quiet updates.
• Built-in Computer Use with macOS Accessibility setup and intent-scoped execution.
• In-app plugin marketplace, portable skill import, and guarded Cos self-management.
• Verified update downloads with SHA-256, bundle identity, version, and structural signature checks.
• Secure BYOK storage through device-only macOS Keychain items.

Downloads

• Cos-1.0.0.dmg — drag-and-drop app image for Apple silicon.
• Cos-1.0.0-macOS-arm64.zip — updater-compatible app archive.
• Cos-Source.zip — source snapshot.
• SHA256SUMS.txt — checksums for release artifacts.

Signing note

This community build is ad-hoc signed and structurally verified, but it is not Developer ID signed or Apple-notarized. macOS may require System Settings → Privacy & Security → Open Anyway on first launch. Review the repository before granting Full Access or Accessibility permission.

Requirements

• Apple silicon Mac
• macOS 15 or later