app-console-keys — console chassis and F-key framework

app-console-keys is the always-installed base chassis of os-console. All other console modules — email, content, SLM monitoring, and the rest — are optional cartridges that plug into the framework app-console-keys defines. The module is mandatory: an os-console binary built without it will not compile.

Naming note: "keys" in app-console-keys refers to keyboard function keys — the F1 through F12 strip that navigates between cartridge slots. It does not refer to cryptographic keys. Cryptographic pairing and machine-based authorization are implemented by system-gateway-mba, a separate crate.

[edit]The Cartridge trait

app-console-keys defines the Cartridge trait — the interface every app-console-* module must implement. The trait is minimal: a module declares which F-key slot it occupies, what to render when that slot is active, and how to handle keyboard input while active. The chassis handles everything else: slot registration, input dispatch, focus management, and the status bar.

Because cartridges are compiled directly into the os-console binary rather than loaded at runtime, the trait is a compile-time contract. A module that fails to implement it produces a build error, not a runtime failure.

[edit]The F-key navigation strip

The primary interface element managed by app-console-keys is the horizontal F-key tab strip at the top of the console. The strip shows one slot per registered cartridge. The active slot is highlighted; inactive slots are greyed when not installed.

The strip does not re-order slots at runtime. Each cartridge's slot position is fixed at the F-key number it claims. app-console-input is permanently fixed at F12 per SYS-ADR-10.

[edit]The status bar

The app-console-keys status bar runs along the bottom of the console and is always visible, regardless of which cartridge slot is active. It displays:

Component	Content
Identity	Username and tenant set during the pairing ceremony
Authorization state	MBA LINK ACTIVE, MBA LINK INACTIVE <reason>, or MBA LINK PENDING
Active slot	Name of the currently focused cartridge
SLM tier	Tier A (local), Tier B (cloud burst), or Tier C (frontier API)
Session duration	Elapsed time since console start

The tier indicator reflects the last routing decision made by the inference gateway. It does not poll the gateway — it updates when a request is routed.

[edit]Authorization client

app-console-keys maintains the outbound machine-based authorization connections to paired os-* services. Each pairing is independent: the console can hold an active link to os-totebox while the link to os-privategit is inactive.

When an authorization link is inactive, the affected cartridge degrades gracefully. Locally cached content remains accessible; backend requests fail with an explicit status rather than silently. No cartridge crashes the chassis when its backend is unreachable.

[edit]Configuration

Profile-based configuration is stored at ~/.config/os-console/config.toml. The configuration file controls which backend services the console attempts to pair with at startup, display preferences, and the SSH server port (if the SSH server feature is compiled in).

[edit]PDF rendering and graphics support

app-console-keys provides the graphics infrastructure used by cartridges that render images or PDFs. PDF pages are rendered to RGB bitmaps using the pdfium-render library. The display path uses the Kitty graphics protocol as the primary path, with Sixel encoding as a fallback, and an error message for terminal environments that support neither.

[edit]See also

• console-os — the os-console product overview, including the F-key surface and operating modes
• os-console-platform — the complete cartridge architecture and F-key map
• app-console-input — the F12 mandatory input gate; always compiled alongside app-console-keys
• machine-based-auth — the authorization mechanism the chassis client manages
• three-ring-architecture — the Ring 1/2/3 architecture the authorization client connects to