docs: anchor each subsystem page to its package group; make group READMEs thin tables

core.md read as a type grab-bag: LLM wire vocabulary up front, the agent/loop story buried, and no correspondence to packages/core. It now opens on the packages/core control spine — the package-by-package loop map with a Page column into session/system-prompt/tools/scope — and keeps only what the spine group declares plus the repo-wide patterns: the Agent handle with its delivery/cancellation/interception contracts, the SessionEvent envelope, branded ids, the …Map pattern. The conversation vocabulary (Message/ContentBlock, the model request, adapters — 17 type-equiv blocks) moves to llm-streaming.md, which now declares packages/llm end-to-end; the duplicate ContentBlockMap paste near its seam section folds into the moved section, and the manifest, LINK_MAP, README table rows, website label (Core data structures → Core), and inbound anchors follow.

Every packages/<group>/README pair is now a thin front door in one shape: a why-first intro (bash's seam-pattern-first paragraph rewritten as 'shell execution for the agent'), the package table, and a closing pointer to the owning docs/subsystems page — the bash-style table stays the load-bearing middle. Load-bearing trailing paragraphs relocate rather than vanish: the fs no-timeout rationale becomes a filesystem.md section (both languages), session's four sectioned tables merge into one 12-row table, examples' legacy-bin H2 collapses to a pointer at jsonrpc-demo's README, and design rationale that already lives in an Agent Note or subsystem page is now linked instead of restated. All 40 pair records re-recorded.

packages/web/README.i18n.yaml

@@ -2,5 +2,5 @@
 # side as of the last confirmed-consistent state. Both languages carry equal authority;
 # after editing either side, bring the other along and re-record with:
 #   pnpm run verify-translation-pairing --write packages/web/README.md
-README.md: 65b3dde1e2f9c35c308a10ca80245064f7a0361e
-README.zh.md: 43b8b7d9c53336e984d9c61fa9b612fc1733e31f
+README.md: 811c8b3439a8962116df0e8b3ab4f6e282ecb3d2
+README.zh.md: e328447d5d026c0abc815b269179ba6c4cd9acfc

packages/web/README.md

@@ -14,3 +14,5 @@ This family provides provider-neutral web search and fetch operations plus the m
 | [`tool-web/`](tool-web/README.md) | Exposes web search and fetch to the model | registers on `ctx.tools` |
 
 The [web capability decision](../../.agents/notes/implemented/architecture/2026-06-24-web-capability-seam.md) records why search and fetch share one provider-selection service.
+
+The subsystem reference — search/fetch requests and results, availability, `WebError` — is [docs/subsystems/web.md](../../docs/subsystems/web.md); rationale (including deferred SSRF protection) in the [web capability seam Agent Note](../../.agents/notes/implemented/architecture/2026-06-24-web-capability-seam.md).

packages/web/README.zh.md

@@ -14,3 +14,5 @@
 | [`tool-web/`](tool-web/README.md) | 向模型公开 web 搜索和抓取 | 注册到 `ctx.tools` |
 
 [web 能力决策](../../.agents/notes/implemented/architecture/2026-06-24-web-capability-seam.md)记录了搜索和抓取共用一项提供方选择服务的原因。
+
+子系统参考——搜索/抓取请求与结果、可用性、`WebError`——见 [docs/subsystems/web.md](../../docs/subsystems/web.md)；依据（含延后的 SSRF 防护）见 [web 能力 seam Agent Note](../../.agents/notes/implemented/architecture/2026-06-24-web-capability-seam.md)。