kandev/docs/plans/managed-runtime-default-activation/task-02-activate-defaults-at-startup.md

id, title, status, wave, depends_on, plan, requirements, acceptance_criteria, system_design

id	title	status	wave	depends_on	plan	requirements	acceptance_criteria	system_design
02-activate-defaults-at-startup	Activate defaults during startup	done	2	01-reconcile-default-generations	plan.md	REQ-AGENTS-RUNTIME-UPDATES-002	AC-AGENTS-RUNTIME-UPDATES-002.1 AC-AGENTS-RUNTIME-UPDATES-002.2 AC-AGENTS-RUNTIME-UPDATES-002.4 AC-AGENTS-RUNTIME-UPDATES-002.5 AC-AGENTS-RUNTIME-UPDATES-002.6	../../specs/agents/system-design/runtime-default-activation.md

Task 02: Activate Defaults During Startup

Summary

Wire default-generation reconciliation into service startup. The backend must finish this operation before discovery, probes, launches, or readiness.

In scope

• Build trusted generations from registered managed agents.
• Run reconciliation before runtime consumers start.
• Stop startup when reconciliation returns an error.
• Add structured logs for changed generations and errors.
• Prove that later resume commands use the reconciled effective version.

Out of scope

• npm metadata requests or candidate ACP probes during startup.
• Replacement of active agent processes.
• Frontend changes.

Acceptance

• Startup removes stale selections before any effective-version consumer starts.
• An unchanged generation preserves a selection through another startup.
• A reconciliation error prevents readiness and leaves the operation retryable.

Verification

go test ./internal/backendapp ./internal/agent/registry ./internal/agent/hostutility ./internal/agent/runtime/lifecycle ./internal/agent/settings/controller -run 'ManagedRuntime|RuntimeVersion|AgentUpdate|BuildAgentCommand' -count=1

Run the command from apps/backend.

Files likely touched

• apps/backend/internal/backendapp/services.go
• apps/backend/internal/backendapp/managed_runtime_defaults_test.go
• apps/backend/internal/agent/runtime/lifecycle/managed_runtime_command_test.go
• Focused registry, host-utility, or Settings tests affected by startup order.

Dependencies

Task 01.

Risks

• Reconciliation must run before a boot probe reads the old selection.
• Mock and custom agents must remain outside the built-in managed generation list.

Parallelism

sequential

Inputs

• Task 01 store contract.
• docs/specs/agents/system-design/runtime-default-activation.md
• Existing backendapp.provideServices and effective-version command builders.

Results

Startup now reconciles managed runtime generations after trusted agent registration and before discovery. Reconciliation errors are logged and returned from provideServices, preventing readiness; future launches fall back to the reviewed default when a selection was cleared.

Verification: the work-order command passed, including backendapp, registry, hostutility, lifecycle, and Settings controller tests.