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Termind architecture

Termind is one application target, one unit-test target, and one first-party package: AgentKit, developed in a sibling repository and consumed through SPM. Inside the app target, directories describe dependency boundaries even though Swift does not enforce them as separate modules. The package boundary is enforced, which is the point of it.

Dependency direction

  • Domain contains platform-independent values and rules.
  • Application contains repositories, feature state, use cases, events, and service protocols.
  • Infrastructure implements persistence, security, SSH, and SFTP clients.
  • Features contains SwiftUI presentation and sends intents to Application.
  • Platform/macOS contains AppKit adapters.
  • App constructs dependencies and owns application/window lifetimes.

There is deliberately no Core or generic shared layer. A value belongs to Domain, orchestration and ports belong to Application, concrete I/O belongs to Infrastructure, and presentation-only parsing or formatting stays with its Feature. This prevents a catch-all directory from bypassing dependency review.

Domain must not import SwiftUI, SwiftData, AppKit, Ghostty, CSSH2, or OpenSSL. Views must not construct network clients, access SwiftData/Keychain directly, or coordinate cross-domain cleanup. Runtime side effects belong to application services and durable outbox handlers.

The app remains one target, so ArchitectureBoundaryTests enforces the framework and concrete-client restrictions that directory layout alone cannot — including that no type AgentKit owns is redefined here.

State lifetimes

  • Repository snapshots are application-wide and shared by every window.
  • A window owns one top-level shell, quick-open, and context-panel state.
  • Metrics is a fixed window destination below Welcome and above the Vault group.
  • The shell always starts with Vault and Assistant; Settings is the final Navigator page after the dynamic SSH/SFTP Workspaces.
  • Vault owns its navigation column, including quick-connect Recents, and routes for Hosts, Keychain, Snippets, Known Hosts, Welcome, and Host Editor. These routes never enter the Workspace deck.
  • Known Hosts is an independent Vault card manager below Snippets. Host edits and deletion never move or remove trust records. Plain endpoints and OpenSSH |1| hashed endpoints use one matcher across all SSH callers. Hashed tokens retain their original hostname wire field; their port field is ignored because the port is part of the hashed input. No Host record is required to retain trust.
  • SSH folder imports stage selectable public metadata in a window-owned model; their actor-owned reader retains private keys until commit or cancellation. File picking and native drag-and-drop feed the same source validation and preview. File access is scoped to explicitly selected directories/files. Config parsing never executes commands. New credentials are written before a single Vault snapshot save and removed on failure. Existing records are never overwritten. Imported trust does not clear existing mismatch warnings.
  • Assistant owns its conversation list through AssistantLibraryModel; conversations are not panes and do not participate in Workspace drag, split, close, or reconnect lifecycles.
  • A workspace owns SSH/SFTP/serial panes plus its session-scoped assistant conversation. Workspace content is full width and has no left sidebar.
  • Session models own live SSH/SFTP/serial resources and terminal/file-browser state.
  • Settings uses app-wide preference storage but window-scoped navigation. It opens as a top-level window destination, remembers the content it replaced, and restores that destination when its index page goes back.
  • App appearance is an app-wide UserDefaults preference, defaulting to the system. The app delegate owns AppAppearanceController, which applies changes through NSApplication.appearance so existing and new windows, native controls, and terminal surfaces inherit one appearance without rebuilding sessions. Following the system clears the override; explicit light/dark choices reuse the corresponding terminal theme.
  • Opening at login is SMAppService's registration, not a preference. The user can revoke it in System Settings without telling the app, so LoginItemController reads the system status every time Settings is shown rather than mirroring it into UserDefaults. Only how that launch behaves is stored here. A quiet login launch hides the app rather than suppressing its window, because a quiet login launch must not present an empty foreground window.

Repository data is persistent truth. Runtime connection state is kept in a connection registry and is never persisted onto domain records.

SSH command history is created only after an authenticated shell-integration start event. A matching completion event enriches that row with exit status and the duration measured by the remote shell; both remain optional so interrupted commands, old protocol events, and history migrated from older versions preserve an honest unknown outcome. Duration is never inferred from client receive time, because SSH buffering can deliver start and completion events together.

Feature views receive aggregate-facing Application Models rather than a generic store API: HostLibraryModel, CredentialLibraryModel, KnownHostsLibraryModel, SnippetLibraryModel, ForwardingLibraryModel, TransferLibraryModel, AIConfigurationModel, SkillLibraryModel, CommandHistoryModel, and ToolAuditModel. Aggregates that share one persisted vault snapshot still expose separate intent surfaces, so a feature cannot gain unrelated write operations merely because its records are saved together.

The shared Vault transaction is isolated behind VaultStore. Feature facades keep their backing aggregate private, and Terminal/SFTP sessions depend on the narrow RemoteSessionHostStore port rather than the complete Vault mutation surface.

Serial sessions are temporary and local: IOKit/termios discovery and descriptors stay in Infrastructure, parameters live only with the open pane, and no serial path is persisted or exposed as an Agent host.

Window navigation has one Navigator plus three tool sidebars: Assistant, Snippets, and History. Dynamic SSH/SFTP containers are consistently named Workspaces; “tab” is reserved for keyboard or native UI tab semantics. Vault selection belongs to VaultPageStates, not to sidebar state.

Speech authorization and callbacks

Speech service and coordinator state belong to MainActor. System authorization callbacks can arrive on arbitrary queues; SFSpeechRecognizer.queue controls recognition callbacks, not authorization callbacks. The speech authorization handler is created in a nonisolated factory as an explicitly Sendable closure that only resumes its checked continuation. The awaiting service returns to MainActor to interpret the result. Moving work to the main queue inside an actor-inherited callback is too late to avoid its entry isolation check.

Authorization does not own a recording session: the coordinator rechecks its session token after waiting, so a cancelled request's late result cannot start recording or affect a newer session.

Agent runtime and security

The runtime is AgentKit, a separate package with no dependencies and no knowledge of hosts, transports, or SwiftUI. What Termind keeps is everything that reaches a machine or a person: the SSH and SFTP tools, the connection pool, the Vault resolver, the SwiftData store, and every view.

The two meet at four seams, all additive:

  • AgentToolCatalog.registry(builtIn:additional:). The package's built-in tools are selected by AgentToolGroup — scratch, web, user interaction, planning, tasks, skills, MCP — and TermindAgentTools supplies ours after them, so a Termind name can never shadow a built-in and a remote MCP name can shadow neither.
  • AgentToolServices, a typed bag a run carries to the tools it registered. AgentSSHInteraction travels in it, which is what keeps credential and host-key prompts out of the package's own protocols — and, structurally, off AgentEventChannel and out of durable history.
  • TermindAgentPolicy, which owns the texts and judgements that are ours: the system prompt, the plan contract, and the ssh_exec rule injected into AgentPlanModeHook.hostDecision. The package ships neutral defaults for each and Termind's stay byte-identical to what shipped, because every provider cache is a prefix cache.
  • TermindAgentPresentation, which extends the package's open card vocabularies with the values only we need — sshConnecting, remoteFile, and the rest. Their raw values are unchanged, so cards persisted before the split still decode and still render.

AgentRuntime is an actor holding a run's state — transcript snapshot, tool registry, steering queue, secret broker — and the loop over it. Each phase of the loop is a separate value it drives:

  • AgentContextPipeline rewrites what is sent at the model boundary: tool results reordered to match the calls they answer, orphaned results dropped, older results trimmed head-and-tail, session context inserted in front of the turn it describes. It shapes only the request. Run snapshots and stored history keep everything.
  • AgentTurnDriver streams one assistant turn and assembles its tool calls.
  • AgentToolScheduler plans and runs the turn's batch.
  • AgentToolExecutor takes one call through schema validation, preflight, the card, hooks, authorization, and execution, in that order.
  • AgentEventChannel is the single ordered path for events, fanning out to the UI and to a serial durable recorder.

OpenAI Responses, OpenAI Chat Completions, Anthropic Messages, and Gemini are adapters at the LLM boundary. Models without tool capability receive no tools. Stop cancels the active stream and actions that have not started; steering messages are consumed at the next turn boundary.

Model purposes are chat, embedding, rerank, image_generation, and video_generation. Only recognised purpose values from model discovery are asserted as reported metadata. Unknown values, including Anthropic's model object discriminator, leave catalog and name inference available and otherwise default to chat. Only chat models enter conversation pickers. Persisted unknown purpose strings also default to chat; there are no legacy purpose aliases.

A turn's tool calls run concurrently only when every call in it is marked parallel; one sequential call makes the whole turn serial rather than being fenced into its own segment. Concurrency is declared per tool and may be overridden per call by preflight — ssh_exec is parallel exactly when CommandRiskClassifier proves the command safe, the same evidence that decides its safety. MCP tools are parallel by default; a server's destructive hint or Ask First makes them sequential, so remote metadata can only tighten concurrency, never grant it. Whatever the order of execution, results reach the transcript in the order the model asked for them, and every call is answered even when the turn is cancelled or refused — an assistant turn with unanswered tool calls is rejected outright on the next request.

Approvals and agent questions are queued and presented one at a time. Run state is derived from what is outstanding rather than asserted by whichever call moved last.

Extension points, all additive: AgentToolCatalog registrations for tool definitions, AgentToolServices for what a host lends them, AgentLoopHook for willExecute / didExecute / shouldStop, AgentContextTransforming for the model boundary, AgentModelStreaming for providers. Authorization is deliberately not among them — AgentApprovalHandling is a structural stage of the executor that no configuration can remove, and hooks run on either side of it.

Skills are the one exception to "tool output is data". A skill is a Markdown procedure the user installed through Settings; only SkillLibraryModel writes one, so no tool, MCP server or fetched page can add, edit or enable a skill. That provenance is what lets load_skill return a body outside the <untrusted-data> framing every other built-in result carries, and the system prompt states the boundary: the instructions may be followed, whatever they then cause to be read comes back through the ordinary tools and is untrusted as usual. A skill authorizes nothing — imported allowed-tools is recorded and never honoured, on the same footing as an MCP annotation. The catalog the model sees is names and descriptions only, injected at the model boundary by AgentSkillCatalogInjection rather than into the system prompt, for the prefix-cache reason AgentSessionContextInjection states; bodies arrive only through load_skill, which is .locallyReadOnly and therefore allowed in every permission mode and while planning. The enabled set is snapshotted when the run starts, like isPlanning, and is empty for a model without tool capability, so the catalog never names a tool the run was not given. A loaded skill is exempt from AgentToolResultTrimming — it is the procedure still being followed rather than output already reasoned about — and bounded instead by AgentSkill.maximumBodyBytes. AgentSkillLibrary ships starter skills that are copied in once, tracked by a generation mark so a deleted one never returns; the only way back is resetToBuiltInSkills, which replaces the library wholesale and is confirmed before it runs.

Tools never receive a reference to the interactive PTY. Server commands use a dedicated SSH exec channel and file operations use run-scoped SFTP clients. Vault secrets are resolved behind AgentHostResolver. User-entered secrets are single-use handles bound to run, tool, host, and purpose; plaintext is passed directly to the executor and is excluded from model input, reviews, events, logs, and SwiftData. Fetch treats public HTTP(S) reads as locally read-only and routes private or otherwise non-public unicast targets through the active permission policy. DNS is revalidated on every redirect; a redirect that first enters a restricted origin pauses for another authorization decision. Explicit request headers follow every redirect, including cross-origin redirects, to match curl -H -L; sensitive values are redacted from review, UI, and durable history. MCP discovery retains schemas and annotations, but remote annotations are risk hints rather than proof of safety.

AgentScratchWorkspace is a per-conversation staging directory under Application Support, inside the sandbox container, named for the app that owns it (TermindAgentPolicy.scratchDirectoryName) and deleted with the conversation that owns it. Paths are relative, .. is refused rather than resolved, symlinks are refused even when they point back inside, and every resolved path is proven to still be under the scope; writes are bounded per file, per conversation, and by entry count. It is an actor, so it is also the per-path mutation queue — a read and a write of the same file in one batch serialize there rather than by taking the whole turn serial, which is why every scratch tool is parallel. scratch_pull and scratch_push move bytes between a host and the workspace without the bytes entering the transcript, so a remote file can be pulled, edited and pushed back without a copy of it crossing the model boundary in either direction; scratch_edit returns a unified diff rather than the new file for the same reason. scratch_search recursively searches UTF-8 content inside that same scope and returns bounded matching-line previews, so locating a small region does not require reading a large staged file into the transcript. scratch_pull and scratch_push are Termind's rather than the package's, precisely because they are the two ends that touch a host. The SFTP tools are unchanged and know nothing about the workspace. Because a push is approved by filename rather than by content, its preflight puts the size, digest and a redacted head into the approval reasons, and binds the approval to that digest through execution-only metadata so a file rewritten while the user was deciding is refused rather than written.

The permission modes share structural validation but differ at the action gate. Safety is a property of the call, established locally: locallyReadOnly for calls proven to change nothing, locallyContained for calls that change only storage the app owns, and requiresAuthorization for everything else. The first two are allowed in every mode — a staging area that has to be approved into is not a staging area, and dialogs nobody can act on teach the reader to click through the one that matters.

  • Ask for approval executes locally proven read-only and contained calls and presents every other action to the user.
  • Approve for me sends those same non-read-only actions to Security Review. Missing credentials, timeout, transport errors, or malformed review JSON fail closed and are persisted as review failures.
  • Full access skips action approval and Security Review while retaining host-key, secret, schema, host/path, fetch protocol/header/address-classification, sandbox, and tool-capability boundaries.

Agent conversations, runs, visible messages, tool calls/results, and reviews are stored in SwiftData after truncation and redaction. Launch marks unfinished runs interrupted; history is restored but remote actions are never resumed or replayed.

A process that dies mid-batch — force quit, crash, the OS reclaiming the app — leaves tool calls that nothing answered, which the next request would be rejected for. Restore closes that in two steps. Results are recorded as each tool finishes but their transcript rows wait for the run's next snapshot save, so loadConversations first materializes any recorded result whose transcript row was never written. Whatever is still unanswered is answered at the model boundary by AgentUnansweredToolCallRepair, which says the outcome is unknown rather than that the tool did not run: the process died after the command was dispatched, and a model told otherwise would repeat it.

Pro purchases and trial access

ProAccessController owns application-wide StoreKit access and purchase activity. The permanent non-consumable Pro product supports Family Sharing; the separate, zero-price non-consumable trial does not. Trial eligibility comes from verified StoreKit history, including revoked purchases, rather than current entitlements alone. Resolution also includes the verified purchase/update being delivered because history caches may lag behind that result. Concurrent refreshes await the latest resolution before purchase preflight proceeds. The trial expires exactly 14 × 24 hours after originalPurchaseDate; restores and repeated transactions never restart it. A valid permanent entitlement always wins. Product metadata loading is independent of entitlement resolution, and purchasing/pending approval does not replace existing access with an operation state. The trial purchase path checks zero price, product type, sharing settings, and availability of the permanent price before invoking the App Store.

Domain's ProTrial contains only date and history rules; StoreKit stays outside Domain. Infrastructure's TrialClock persists a per-original-transaction maximum observed date in UserDefaults. This best-effort rollback guard can only shorten a verified trial and is never a second source of purchase eligibility. Legacy local proofs, trial Keychain keys, and trial CloudKit records are neither read nor written; previous trial users may claim the new IAP. Vault sync and credential storage remain separate from commerce.

Trial expiration is rechecked on app activation and at most every minute while an active trial is observed. Expiration disables gated features, but previously granted workspace composition remains available for the current launch so an existing workspace is not dismantled. A fresh launch has no such workspace grant. The review demo only simulates expired access and cannot grant paid or trial access.

Server metrics

Debug screenshot launches inject a frozen ServerMetricsModel into AppModel. Its in-memory preferences never read or write saved monitor configuration, and it cannot start samplers or host-key discovery. The metrics overview and detail fixtures render the production views using deterministic, fictitious data. Screenshot launches explicitly create an AppKit window hosting the same RootView as the normal WindowGroup and disable restoration; window preparation waits for a visible key-capable window before sizing and activation; their ready log records both focus conditions before capture. Vault captures clear the initial disclosure-button focus without resigning the key window.

ServerMetricsModel is application-owned, with one serial SSH exec sampler per monitored saved host. Metrics navigation and the menu-bar popover consume the same observable rows. Rows are created synchronously from saved selections, before credential resolution or networking starts, and expose connecting, connected/collecting, live, paused, sleeping, and actionable failure states. The menu-bar setting defaults on. Closing the last window keeps the process alive while that setting or any enabled monitor requires it; explicit Quit cancels monitoring. NSWorkspace sleep/wake and native window reopening belong to Platform/macOS, not to the sampling coordinator.

Connection preparation snapshots route, identity, public-key and trust metadata on MainActor. SSHConnectionPreparation resolves the Sendable secret store on a detached worker: Keychain access must never block first paint or state updates. Cancellation is checked again before connecting, so late credential results cannot revive a paused monitor. Secrets remain memory-only, are never written with selections or history, and are cleared when monitoring is paused/removed or the app terminates. Known-host verification still gates every SSH connection; interactive trust and authentication are presented in Metrics.

Linux procfs and optional nvidia-smi -q -x are read by Infrastructure with bounded output and command deadlines. GPU failure does not erase base metrics. Servers without NVIDIA hardware omit the GPU section entirely. Missing values and invalid counter deltas remain unknown; remote uptime determines rates. History is an in-memory five-minute window; only host/device selections persist in local preferences. GPU identity uses NVIDIA UUID, and XML external entities are disabled. There is no WidgetKit extension, App Group, remote agent, or dependency on AgentKit for monitoring.

get_metrics gives the built-in Agent and the authenticated MCP server the same read-only view of existing monitoring. MetricsSnapshotReading copies Sendable values on MainActor; tools cannot admit hosts, start sampling, register detail observers, or access authentication state through this port. A structured monitor state accompanies the snapshot independently of localized UI text. The tool validates host IDs against the Agent host listing; known unmonitored targets return not_monitored. It is locally read-only, parallel, and allowed while planning. MCP exports it by default and preserves the injected reader when tools are disabled or re-enabled, under the existing server access and audit rules.

The default output contains core metrics and sample means/peaks over the available points within the preceding five minutes, with actual bounds and per-metric valid sample counts. Optional device, GPU, process, and filesystem sections expose only already collected values; processes retain the existing CPU ordering and are limited to 20 with explicit counts. Each section carries its own timestamp, age, availability and stale flag (30 seconds, or 60 for filesystems). Failed sections may retain older values without presenting them as fresh. Missing/non-finite numbers are null. JSON uses UTC ISO 8601 timestamps, bytes, bytes per second, and percent; process CPU remains 100% per core. This projection belongs to Termind's Agent tools; monitoring itself still has no AgentKit dependency.

MetricsMenuBarController owns an AppKit NSStatusItem and NSPopover for the application lifetime. The menu view receives its monitoring model and open callback explicitly, rather than relying on a window scene's environment. Preference notifications reconcile item visibility without writing defaults back, preventing insertion/render feedback loops.

Metrics overview uses an adaptive grid of compact server cards. Per-window selection opens a fixed two-column detail page. System panels scroll on the left and the native process Table scrolls independently on the right; there is no outer detail-page scroll view or trend tab. CPU breakdown, uptime, load, free/cached memory and per-device traffic/I/O are displayed in separate panels; GPU details join the left column only when hardware has been detected. Process counters are collected only while at least one window observes that host's details; multiple windows still share the same sampler. procfs process CPU is computed from adjacent process/system tick deltas (100% per logical core), RSS uses the remote page size, and PID plus start time prevents reused PIDs from inheriting prior counters. Process reads have separate output and time limits so errors leave base metrics available. No command arguments or process environment variables are collected.

Metrics uses ManagedCardPage/CardTile for the same surfaces, hover, native selection, marquee, drag ghosts, and reordering contract as Hosts. Its local monitor order is persisted independently of Vault host order and moving rows does not reconnect them. Metrics opts into single-click activation; drag gestures retain the shared reordering behavior and Shift-click extends selection without opening details. Add Server is a window-toolbar creation action backed by the shared host chooser; Show in Menu Bar lives only in Settings. The page does not duplicate its title or creation controls inside the card canvas.

Both metrics routes use the shared titlebar search field: the overview filters servers and the detail filters processes, with separate window-owned queries. The process Table has PID first, user-selectable column sorting, and uniform row backgrounds. Overview cards fill the available grid width and omit GPU rows; GPU data belongs to the detail panels. Normal sampling has no redundant Live badge. Free Memory is a contextual localization key, separate from the commerce Free label. Native host-chooser row roots explicitly receive AppModel because an independent NSHostingView does not inherit the parent environment.

Healthy metrics render no status/timer footer. Detail controls (pause/resume, retry, device selection and removal) belong beside the toolbar Back button, not in a duplicate server-name card. Add Server is overview-only. Connection and authentication notices remain visible when action or waiting is required.

Overview cards reserve a fixed instrument-body height. Connecting, initial sampling, paused and attention states replace that body with a centered status instead of appending a footer or expanding authentication controls. Clicking an authentication-required card opens ConnectionJourneyView, not metric detail. Journey owns the familiar identity/passphrase and host-key UI; the metrics coordinator retains the only transport owner. Temporary host-key acceptance is scoped to that enabled monitor and cleared on pause/removal/configuration change. Successful collection completes the Journey before displaying metrics. Rejection pauses monitoring without accepting a key or creating a terminal workspace.

Filesystem panels are identified by mount point, with device path, filesystem type and df capacity. mountinfo major:minor links the mount to per-partition diskstats; whole-device totals still exclude stacked devices and partitions. Capacity refreshes every 30 seconds only while details are observed, with its own bounded command so failures do not discard base samples. Subdirectory bind mounts and pseudo-filesystems are excluded (root overlays and Btrfs subvolumes remain representable). Network metadata classifies sysfs-backed hardware versus virtual interfaces. Hardware interfaces are expanded, virtual ones collapsed; default aggregate traffic uses hardware when available and otherwise non-loopback interfaces. Explicit user selections still override aggregation. TCP counters are host-wide and the traffic ring compares transmitted and received bytes, not link utilization.

The Termind menu-bar popover stacks servers vertically with horizontal separator rules. Each row preserves the overview's horizontal instrument layout through MetricsInstrumentBody, without CardTile backgrounds. Larger fleets scroll vertically. Open and Quit are accessible icon buttons in the upper-right corner. CPU steal is labeled virtualization wait in Chinese; per-core process CPU semantics remain unchanged without an explanatory banner.

The menu popover has one continuous surface: header and rows use matching content insets, separators span the full width, and the list has no nested scroll background/edge effects. Pointer opening resets input modality and clears AppKit's automatic first-button focus after presentation. Real keyboard input keeps the normal accessible focus behavior.

Free metrics admission is capped at three added cards, including paused cards; Pro and an active trial allow unlimited additions. The Application model checks an injected live limit and inserts deduplicated batches atomically, so concurrent windows and bulk selection cannot overrun the cap. Batch admission happens after the chooser dismisses, before presenting the existing Pro paywall. Restored or previously purchased configurations are retained rather than deleted on downgrade; all retained cards count against future additions.

Settings replication

The iCloud page has one master preference and separate Vault/Settings selections. Vault is selected by default; Settings is opt-in. Disabling the master preserves both selections. Upgrading with Vault sync disabled keeps the master disabled. Pro access gates both CloudKit coordinators, whose zones, subscriptions, account bindings and journals are independent. Settings use TermindAIConfigurationV1; the existing TermindVaultV1 protocol is unchanged.

SettingsSyncPersistence commits configuration and upload intent together in SwiftData V14. V13 already exists in installed development stores: its PersistentAIConfigurationSync* names and defaults stay frozen. V14 adds only PersistentTerminalPreferences; the Settings rename preserves the original CloudKit identifiers as well. Providers (including their models), MCP clients, skills, role assignments, model selection, Web Search and Terminal preferences have separate records. Terminal custom configuration text is included. Remote commits refresh the application models without entering the local mutation path. Web Search and Terminal preferences are migrated from UserDefaults once, then mirrored there for existing runtime readers. Active agent runs retain their configuration snapshots. Conversations, approval mode, local MCP listener settings and other app preferences are excluded. Only explicitly selected settings are projected, never all defaults.

The journal retains tombstones and unresolved references across partial fetches. Preexisting defaults use baseline versions and yield to cloud records. Built-in skills use stable IDs; migration preserves customized skills and records deleted built-ins. Duplicate skill names or MCP namespaces retain their data but only the lowest UUID is eligible for execution until the conflict is resolved.

AI credentials use AISecretStore. First Settings sync checks the iCloud account before migrating local Keychain entries. A verified cloud copy and durable local storage marker precede local-copy cleanup. Migrated entries remain in iCloud Keychain when configuration sync pauses. Production reads do not cache secrets; missing synchronized credentials may arrive later. Pending credential deletion markers prevent delayed Keychain deliveries from reviving a cleared value. Explicit credentials stay out of CloudKit; custom MCP headers and custom terminal configuration are ordinary user-authored settings. The private-account sync adapter is the only additional trusted source of skill-library snapshots.