refactor: extract shared agent loop engine

README.md

@@ -23,6 +23,10 @@ Version `0.1.x` contains the converged foundation layer:
 - streamed tool-call recovery checks for missing required arguments.
 - LLM binding, response normalization, streaming assembly/watchdogs, retry
   classification, runaway recovery, and physical-call orchestration.
+- model profiles, thinking/history normalization, and multi-format tool-call
+  parsing;
+- parallel tool execution and the complete agent-loop orchestration engine,
+  with product behavior isolated behind typed hooks.
 
 The initial extraction is based on the already-merged integration branches:
 
@@ -32,10 +36,10 @@ The initial extraction is based on the already-merged integration branches:
 Those revisions are provenance, not runtime dependencies. AgentCore tests and
 builds without either product checkout.
 
-The agent loop remains in the products until tool execution, model profiles,
-tool-call parsing, and execution-context storage have converged boundaries.
-The LLM runtime accepts the three remaining product decisions through explicit
-hooks: wall-deadline lookup, provider-chain state, and sticky-session policy.
+The shared loop accepts product decisions through explicit hooks. Products own
+execution-context storage, endpoint registries, metering, deadline policy,
+result spilling and aggregate budgets; they no longer need private copies of
+the orchestration or parsing engines.
 
 ## Repository boundary
 
@@ -115,7 +119,8 @@ edit both products' core copies, that is evidence it belongs here.
    classification, and explicit product hooks are shared.
 3. **LLM runtime** (complete): binding, calls, streaming, response
    normalization, runaway recovery, and the public `llm_client` facade.
-4. **Agent loop:** model/tool parsing, tool execution, and `agent_loop`.
+4. **Agent loop** (complete in AgentCore): model/tool parsing, hook-driven tool
+   execution, and `agent_loop` orchestration.
 5. Remove product compatibility facades after downstream imports have moved to
    `agent_core`.
 

agent_core/runtime/loop/__init__.py

@@ -1,5 +1,6 @@
 """Shared loop foundation primitives."""
 
+from agent_core.runtime.loop.agent_loop import AgentLoopHooks, run_agent_loop
 from agent_core.runtime.loop.compact import (
     DefaultCompactionPolicy,
     DefaultMessageCompactor,
@@ -28,28 +29,56 @@
     NullTrimmer,
     TaskBoundaryTrimmer,
 )
+from agent_core.runtime.loop.model_profile import (
+    DefaultThinkingParser,
+    HistoryPolicy,
+    ModelProfile,
+    NativeMessageNormalizer,
+    configure_model_registry,
+)
+from agent_core.runtime.loop.tool_call_parser import (
+    DefaultToolCallParser,
+    MultiFormatToolCallParser,
+)
+from agent_core.runtime.loop.tool_exec import (
+    DefaultToolResultPostProcessor,
+    ToolExecutionHooks,
+    execute_tools,
+)
 
 __all__ = [
     "RUNAWAY_STATE_KEY",
     "TRUNCATION_CONTINUATION_GUIDANCE",
+    "AgentLoopHooks",
     "DefaultCompactionPolicy",
     "DefaultMessageCompactor",
+    "DefaultThinkingParser",
+    "DefaultToolCallParser",
+    "DefaultToolResultPostProcessor",
+    "HistoryPolicy",
     "LLMCallExhausted",
     "LLMDeadlineExceeded",
     "LLMReasoningRunaway",
     "LLMStreamStalled",
     "MessageTrimmer",
+    "ModelProfile",
+    "MultiFormatToolCallParser",
+    "NativeMessageNormalizer",
     "NullTrimmer",
     "TaskBoundaryTrimmer",
     "ThinkTagSplitter",
+    "ToolExecutionHooks",
     "bind_max_tokens",
     "bind_session_id",
     "bind_temperature",
     "bind_tools",
     "call_llm",
+    "configure_model_registry",
+    "execute_tools",
     "extract_final_content",
     "extract_leaked_reasoning",
     "extract_model_name",
     "extract_usage",
     "is_truncated_with_text",
+    "run_agent_loop",
 ]