docs(subsystems): open core.md on agent creation/ownership and the Agent contract; enforce a complete folder index

core.md claimed to be the packages/core reference but opened on repo-wide type patterns and never documented the ownership vocabulary: AgentHandle, CreateAgentOptions, ResumeAgentOptions, and AgentFactory were TYPE_LINK_EXEMPTIONS pointing at a package README, invisible to the folder that calls itself the type reference. The page now reads spine map -> creation and ownership (AgentHandle pasted; the options and factory summarized with links into the generated registry section) -> the Agent handle (AgentStatus, AgentOptions, SteeringOutcome, SteeringReceipt, and SettleReason now pasted; the one settlement prose wall split by topic; delivery vocabulary ordered as a message travels) -> initiator -> interception -> a Sessions summary -> the ToolDefinition pointer -> an explicitly framed repo-wide patterns tail (the ...Map pattern, branded ids). The duplicate SessionEvent paste is gone -- session.md owns it and LINK_MAP follows -- the four ownership types moved from TYPE_LINK_EXEMPTIONS into LINK_MAP -> core.md, and three dead LINK_MAP entries (ContinuationDecision, ContinuationStop, HookContext) no longer name types absent from the source tree. The "what this page owns" meta-section folds into the intro.

The subsystems README index silently lost tasks.md and session-reference.md on both language sides during a base absorption; the rows are restored and scripts/project-doc-site.spec.ts now fails when any page misses either side of the index (proven red on a removed row). tools.md links ToolSchema to its llm-streaming.md declaration instead of calling it core; subagent.md links AgentHandle and CreateAgentOptions.seed to the new section. A new Agent Note records the package-anchored page-scoping decision; the 2026-06-20 catalog note marks its spine-vs-seam rule superseded as the page-scoping rule while keeping the type-equiv mechanism current, and docs/AGENTS.md cites the new note.

scripts/type-equiv.manifest.json

@@ -22,17 +22,17 @@
       "source": "packages/llm/llm/src/message.ts"
     },
     {
-      "doc": "docs/subsystems/core.md",
+      "doc": "docs/subsystems/llm-streaming.md",
       "symbol": "ContextForm",
       "source": "packages/llm/llm/src/message.ts"
     },
     {
-      "doc": "docs/subsystems/core.md",
+      "doc": "docs/subsystems/llm-streaming.md",
       "symbol": "ContextSnapshotSection",
       "source": "packages/llm/llm/src/message.ts"
     },
     {
-      "doc": "docs/subsystems/core.md",
+      "doc": "docs/subsystems/llm-streaming.md",
       "symbol": "ContextFormed",
       "source": "packages/llm/llm/src/message.ts"
     },
@@ -57,12 +57,12 @@
       "source": "packages/llm/llm/src/types.ts"
     },
     {
-      "doc": "docs/subsystems/core.md",
+      "doc": "docs/subsystems/llm-streaming.md",
       "symbol": "LlmModelDiscoveryRequest",
       "source": "packages/llm/llm/src/types.ts"
     },
     {
-      "doc": "docs/subsystems/core.md",
+      "doc": "docs/subsystems/llm-streaming.md",
       "symbol": "LlmDiscoveredModel",
       "source": "packages/llm/llm/src/types.ts"
     },
@@ -111,11 +111,6 @@
       "symbol": "LlmCallConfigAdapterDefaults",
       "source": "packages/llm/llm/src/call-config.ts"
     },
-    {
-      "doc": "docs/subsystems/core.md",
-      "symbol": "SessionEvent",
-      "source": "packages/core/session/src/types.ts"
-    },
     {
       "doc": "docs/subsystems/core.md",
       "symbol": "InboxTarget",
@@ -1689,6 +1684,21 @@
       "doc": "docs/subsystems/session-projection.md",
       "symbol": "ProjectionChangeListener",
       "source": "packages/session/session-projection/src/index.ts"
+    },
+    {
+      "doc": "docs/subsystems/core.md",
+      "symbol": "AgentHandle",
+      "source": "packages/core/agent/src/index.ts"
+    },
+    {
+      "doc": "docs/subsystems/core.md",
+      "symbol": "AgentStatus",
+      "source": "packages/core/agent/src/types.ts"
+    },
+    {
+      "doc": "docs/subsystems/core.md",
+      "symbol": "AgentOptions",
+      "source": "packages/core/agent/src/types.ts"
     }
   ]
 }