ironclaw/crates/loop/ironclaw_loop_host

ironclaw_loop_host

The concrete implementation of every ironclaw_loop_contracts port over kernel services — the one crate licensed to hold both Loop*Port types and kernel handles in the same module. Since the WS3 sheds it also owns the model-gateway adapter (the family's single sanctioned provider client), the model-route policy vocabulary, the driver-host port adapters, progressive tool disclosure, and the loop tier's system-prompt content assets.

• Family / layer: loop / loops · Package: ironclaw_loop_host · Manifest: crates/loop/ironclaw_loop_host/Cargo.toml
• Use this when: implementing or decorating a loop port over a kernel or domain service; adding prompt-safe context builders; changing tool disclosure or model routing.
• Don't use this when: deciding what a turn does next → ironclaw_agent_loop; composing the decorator chain for a claimed run or registering drivers → ironclaw_turn_runner (the runner orders the pieces; this crate supplies them); policy/audit middleware → ironclaw_hooks.

Public surface

• Base Loop*Port adapters: capability port + surface filtering (capability_port.rs, capability_surface_filter.rs, capability_allow_set.rs), input queue, cancellation, compaction, checkpoint store, budget accountant, subagent-spawn port.
• Model gateway (model_gateway.rs, thread_resolving_model_gateway.rs) and the model_routes.rs policy vocabulary (ModelRoute, ModelSlot, ModelRouteResolver, …).
• Driver-host port adapters (driver_host_port_adapters.rs): HostManagedLoopCheckpointPort, HostManagedLoopProgressPort, NoExtraLoopInputPort.
• Progressive tool disclosure (tool_disclosure*.rs): catalog/selector, the deferring LoopCapabilityPort decorator, the REBORN_TOOL_DISCLOSURE switch.
• Prompt-context builders (identity_context.rs, skill_context.rs) and skill_activation/ (the dissolved ironclaw_first_party_extension_ports crate, WS8).
• system_prompt_assets.rs + prompts/*.md — the system-prompt content (composition keeps assembly and on-disk SYSTEM.md seeding, never the text).

Depends on / consumed by

• Normal workspace deps (17): contracts (ironclaw_common, ironclaw_host_api, ironclaw_loop_contracts), kernel services the adapters wrap (ironclaw_capabilities, ironclaw_host_runtime, ironclaw_turns, ironclaw_processes, ironclaw_approvals, ironclaw_resources), domains/substrates the context builders need (ironclaw_filesystem, ironclaw_memory, ironclaw_observability, ironclaw_outbound, ironclaw_safety, ironclaw_skills, ironclaw_threads) — and ironclaw_llm (default-features = false) for the model-gateway adapter alone, an exception by charter (PROPOSAL §6.7.2), not drift.
• Consumed by (4): ironclaw_turn_runner (composes the base adapters into each claimed run's host), ironclaw_composition (assembly), ironclaw_extension_host, and ironclaw_assistant — the last is the measured products → loops debt edge PROPOSAL §6.10.1 scopes (6 files / 4 seams), not a pattern to extend.

Invariants

• No other module may reach a provider client — the gateway is the single adapter; ironclaw_turn_runner must not regain ironclaw_llm (--test reborn_dependency_boundaries reborn_runner_llm_wiring_is_isolated).
• The WS3 shed items are defined here and absent from the runner (--test reborn_runner_sheds).
• skill_activation/ keeps its old crate boundary as a module-import equality (--test reborn_dependency_boundaries dissolved_ports_module_keeps_its_crate_boundary).
• Prompt content stays out of the composition root (--test reborn_composition_boundaries composition_root_embeds_no_prompt_content).
• No decorator performs a turn-lifecycle state transition, and nothing here bypasses CapabilityHost or dispatcher authority paths.

Tests

cargo test -p ironclaw_loop_host
cargo test -p ironclaw_turns -p ironclaw_turn_runner   # when host-port contracts change
cargo test -p ironclaw_architecture_tests              # after dependency/API changes

See also

Family rules: crates/loop/AGENTS.md · working rules: AGENTS.md beside this file · design record: docs/reborn/target-architecture/families/loop.md (§6.7.2).