@xandreed/sdk-core

The pure domain of the efferent agent — entities, ports, and use cases. Runtime dependencies are effect and @effect/ai (provider-agnostic) and nothing else.

This is the inward end of the ports & adapters architecture: cli → sdk-adapters → sdk-core. sdk-core imports nothing from its siblings — it declares what the agent does as Effects over Context.Tag ports; the adapters supply how.

What's inside

• entities/ — Schema-backed types the loop manipulates: Conversation (the AgentMessage union, Checkpoint), AgentContext (context-tree nodes), AgentEvent (the wire event union), Model (selections, roles, the generated context-window catalogue), Settings, Scope, Skill, AgentDefinition, AgentHooks, Job (the control-plane submission unit), Memory, Directive. Pure values, no IO.
• ports/ — Context.Tag services for everything the domain needs from outside: ConversationStore, ContextTreeStore, FileSystem, Shell, Http, WebSearch, AuthStore, SettingsStore, ModelRegistry, LlmInfo, UtilityLlm, Approval, AuthFlow. Each port file pairs its tagged errors with the Tag.
• usecases/ — Effects over the ports: the agent loop (runAgent.ts, agentLoop.ts, promptMapping.ts, agentPhase.ts); the orchestration substrate lifted here from the CLI — agentBus.ts (the Supervisor, exported as type Supervisor = AgentBus; not a Context.Tag port but a per-session stateful value carrying the event sink, threaded via makeAgentBus), buildScopeRuntime.ts (sub-agent spawning over the context tree), codingToolkit.ts (the coding tools), discoverScopeTree.ts, loadTools.ts, schedule.ts, staleness.ts, parseFrontmatter.ts; the loop primitives runContext.ts + tokenBudget.ts; context management (handoff.ts, compaction.ts, compactionContent.ts); approval (autoApproval.ts); and helpers (generateTitle.ts). (Workspace-shaped discovery — loadSkills.ts, loadAgents.ts, loadMemory.ts, teamAgents.ts — lives in efferent.)
• prompts/ — system-prompt strings/functions: handoff.ts, title.ts, plus the shared fleet/scope pieces lifted from the CLI — sections.ts (subAgentsSection / coordinationSection / renderAgentsSection / renderMemorySection) and scopeAgent.ts (renderScopeSystemPrompt). (The root coder prompt coder.ts lives in efferent.)

Rules

• Never import from @xandreed/sdk-adapters or the CLI. If a use case needs a capability, declare a port — the only SDK allowed here is @effect/ai (provider packages live in adapters).
• No try/catch/throw/.catch() in src/ — error handling is Effect's typed errors (Effect.fail, Effect.catchTag, …), enforced by scripts/banTryCatch.ts in bun run typecheck.
• camelCase files export functions; PascalCase files export types / Context.Tag classes. Tags carry a fully-qualified id: Context.Tag("@xandreed/sdk-core/FileSystem").

Part of efferent — an agent runtime on Effect.ts + Bun.