Root wiki: consult sub-wikis as read-only reference for scope/terminology (hybrid)

[ppsplus-bradh]

Summary

Make the monorepo root wiki consult each subproject's sub-wiki as read-only
reference material when writing its repository-wide overview, so the root's
scope/terminology stays consistent with how each subproject describes itself —
without making sub-wiki regeneration an invalidation trigger for the root.

This is the "hybrid" (Option C) from a design discussion: get the
summary-of-summaries consistency benefit while keeping the dependency graph
clean (source → sub-wiki → root as a read-only reference, never an
invalidation edge, so no churn loops).

Background — how the root wiki works today

The root run (recursionRole: "root", src/agent/repository-prompts.ts:32-37)
is told to: not deep-document subprojects; link DOWN to each subproject's
openwiki/quickstart.md; describe repository-wide concerns (architecture, how
subprojects fit together, shared tooling, cross-cutting workflows); and treat
the deterministically-generated openwiki/workspaces.md as the sub-wiki catalog.

The root writes its overview from repo-wide source — the root-excluding-nested
planner-evidence scope excludes generated **/openwiki/** but includes all
subproject source. It regenerates on every recursive run (its no-op check is
repo-wide). So it already reacts to real subproject scope changes via the
underlying source; it just doesn't consult the sub-wikis' own distilled framing.

Read access already exists: src/agent/docs-only-backend.ts gates reads only
by .openwikiignore/.claims (the openwiki-tree confinement applies to
writes only), and the root run is rooted at the repo root — so it can already
read packages/*/openwiki/quickstart.md. No backend or ignore change is needed.

Scope of work

1. Prompt (recursionRoleGuidance("root") in
   src/agent/repository-prompts.ts): add guidance instructing the root to
   consult each subproject's sub-wiki entrypoint (its openwiki/quickstart.md,
   enumerated from openwiki/workspaces.json / openwiki/workspaces.md) for
   scope, naming, and terminology, then write a repo-wide overview that is
   consistent with them — while keeping the existing rules (link down, do NOT
   deep-document or copy sub-wiki content; workspaces.md stays generated).
2. Tests: extend test/agent/repository-prompts.test.ts to assert the root
   guidance directs consulting the sub-wiki quickstarts (and that the subproject
   guidance is unchanged).

Explicit non-goals (keep the dependency graph clean)

• Do NOT add nested **/openwiki/** to the root's planner evidence
  (plannerEvidenceScope("root") stays root-excluding-nested) or to the root
  fingerprint (fingerprintScope("root") stays repo-wide/unscoped). Sub-wikis
  remain a read-only reference, never an invalidation edge — this is what
  prevents a sub-wiki-regen → root-regen churn loop.
• Do NOT have the root deep-document or duplicate sub-wiki content; it
  synthesizes a repo-wide overview and links down.
• No change to the deterministic workspaces.md aggregation.

Acceptance criteria

• Root role guidance instructs consulting each sub-wiki's quickstart for
  scope/terminology consistency, via the workspaces manifest.
• Subproject role guidance and all evidence/fingerprint scoping are
  unchanged (no new invalidation edge; verify plannerEvidenceScope /
  fingerprintScope for root are untouched).
• test/agent/repository-prompts.test.ts covers the new root guidance.
• typecheck / build / lint clean; full test suite green.

[ppsplus-bradh]

Resolved — implemented, reviewed, pushed to PR langchain-ai#439

Commit 6e74852 on feat/recursive-monorepo-docs (pushed). Prompt-only change, as scoped.

What landed: a new bullet in recursionRoleGuidance("root") (src/agent/repository-prompts.ts) directing the root run to CONSULT each subproject's openwiki/quickstart.md (enumerated from openwiki/workspaces.json / the generated openwiki/workspaces.md) as read-only reference — aligning the repo-wide overview's scope, naming, and terminology with how each subproject describes itself, while explicitly not copying/quoting sub-wiki content or substituting it for the repository-wide synthesis. Existing root bullets (link down; workspaces.md is generated) preserved verbatim.

Non-goals held (no invalidation edge / no churn loop): plannerEvidenceScope("root") stays root-excluding-nested and fingerprintScope("root") stays repo-wide — both unchanged. Subproject/default guidance and the workspaces.md aggregation are untouched. Sub-wikis remain a read-only reference, never a trigger.

Read access: already available — docs-only-backend.ts gates reads only by .openwikiignore/.claims (docs-only confinement is writes-only), and the root run is rooted at the repo root. No backend/ignore change needed.

Tests: new root role consults sub-wiki quickstarts as read-only reference in test/agent/repository-prompts.test.ts — asserts the guidance text, its propagation into both planner and page prompts, and that the subproject role does NOT gain the directive. Verified fix-sensitive (fails without the change).

Verification: typecheck ✓ · build ✓ · lint ✓ · full suite 3681 passed / 3 skipped.

Closing as fixed; lands on main when PR langchain-ai#439 merges.