Use Effect fn for RAG helpers

ts/EFFECT_NATIVE_REWRITE_AUDIT.md

@@ -2122,6 +2122,27 @@ Notes:
   - `cd ts && bun run lint`
   - `git diff --check`
 
+### 2026-06-04: Retrieval RAG Effect.fn Helper Slice
+
+- Status: migrated and package-verified.
+- Completed:
+  - `ts/packages/flow/src/retrieval/document-rag.ts` now defines its reusable
+    document RAG query program with `Effect.fn` instead of a function returning
+    `Effect.gen`.
+  - `ts/packages/flow/src/retrieval/graph-rag.ts` now defines the graph RAG
+    query, concept extraction, vector lookup, entity lookup, edge traversal,
+    edge scoring, and synthesis helpers with named `Effect.fn` providers.
+  - Public Promise facades and requestor compatibility surfaces are unchanged.
+  - The focused scan for retrieval `return Effect.gen(...)` helper patterns is
+    clean.
+- Verification:
+  - `cd ts/packages/flow && bunx --bun vitest run src/__tests__/retrieval-rag.test.ts`
+  - `cd ts && bun run check:tsgo`
+  - `cd ts && bun run build`
+  - `cd ts && bun run test`
+  - `cd ts && bun run lint`
+  - `git diff --check`
+
 ## Subagent Findings To Preserve
 
 - MCP/workbench:
@@ -2281,8 +2302,8 @@ Notes:
     slices found no production normal `Error`, raw `try`/`catch`, native
     `switch`, or Effect-focused type assertions under `ts/packages`.
   - Remaining real helper-normalization targets from the fresh sweep are
-    retrieval/document-rag, retrieval/graph-rag, embeddings/ollama, base
-    processor flow helpers, and one workbench atom helper.
+    embeddings/ollama, base processor flow helpers, and one workbench atom
+    helper.
   - Remaining real long-lived native collection targets include base processor
     registries, Librarian service / collection manager state, prompt template
     cache, and a workbench module cache. Local traversal sets and test fakes

ts/packages/flow/src/retrieval/document-rag.ts

@@ -93,12 +93,11 @@ export function makeDocumentRag(clients: DocumentRagClients): DocumentRag {
   };
 }
 
-function queryDocumentRag(
+const queryDocumentRag = Effect.fn("DocumentRagEngine.queryDocumentRag")(function* (
   clients: DocumentRagClients,
   queryText: string,
   options?: DocumentRagQueryOptions,
-): Effect.Effect<string, DocumentRagEngineError> {
-  return Effect.gen(function* () {
+) {
     const collection = options?.collection ?? "default";
 
     const embResp = yield* clients.embeddings.request({ text: [queryText] }).pipe(
@@ -139,4 +138,3 @@ function queryDocumentRag(
 
     return resp.response;
   });
-}

ts/packages/flow/src/retrieval/graph-rag.ts

@@ -149,13 +149,12 @@ export function makeGraphRag(
   };
 }
 
-function queryGraphRag(
+const queryGraphRag = Effect.fn("GraphRagEngine.queryGraphRag")(function* (
   clients: GraphRagClients,
   queryText: string,
   options?: GraphRagQueryOptions,
   rawConfig?: GraphRagConfig,
-): Effect.Effect<GraphRagResult, GraphRagEngineError> {
-  return Effect.gen(function* () {
+) {
     const config = normalizeGraphRagConfig(rawConfig);
     yield* Effect.log(`[GraphRag] Query: "${queryText.slice(0, 80)}..."`);
 
@@ -185,10 +184,11 @@ function queryGraphRag(
 
     return { answer, subgraph: scoredEdges };
   });
-}
 
-function extractConcepts(clients: GraphRagClients, query: string): Effect.Effect<string[], GraphRagEngineError> {
-  return Effect.gen(function* () {
+const extractConcepts = Effect.fn("GraphRagEngine.extractConcepts")(function* (
+  clients: GraphRagClients,
+  query: string,
+) {
     const promptResp = yield* requestClient(
       clients.prompt,
       "extract-concepts-prompt",
@@ -212,22 +212,21 @@ function extractConcepts(clients: GraphRagClients, query: string): Effect.Effect
       .map((concept) => concept.trim())
       .filter((concept) => concept.length > 0);
   });
-}
 
-function getVectors(clients: GraphRagClients, concepts: string[]): Effect.Effect<number[][], GraphRagEngineError> {
-  return Effect.gen(function* () {
+const getVectors = Effect.fn("GraphRagEngine.getVectors")(function* (
+  clients: GraphRagClients,
+  concepts: string[],
+) {
     const resp = yield* requestClient(clients.embeddings, "get-vectors", { text: concepts });
     return resp.vectors;
   });
-}
 
-function getEntities(
+const getEntities = Effect.fn("GraphRagEngine.getEntities")(function* (
   clients: GraphRagClients,
   config: NormalizedGraphRagConfig,
   vectors: number[][],
   collection?: string,
-): Effect.Effect<Term[], GraphRagEngineError> {
-  return Effect.gen(function* () {
+) {
     const resp = yield* requestClient(
       clients.graphEmbeddings,
       "get-entities",
@@ -240,15 +239,13 @@ function getEntities(
     );
     return resp.entities;
   });
-}
 
-function followEdges(
+const followEdges = Effect.fn("GraphRagEngine.followEdges")(function* (
   clients: GraphRagClients,
   config: NormalizedGraphRagConfig,
   entities: Term[],
   collection?: string,
-): Effect.Effect<Triple[], GraphRagEngineError> {
-  return Effect.gen(function* () {
+) {
     const visited = new Set<string>();
     const subgraph: Triple[] = [];
     let currentLevel = new Set<string>(
@@ -301,15 +298,13 @@ function followEdges(
 
     return subgraph.slice(0, config.maxSubgraphSize);
   });
-}
 
-function scoreEdges(
+const scoreEdges = Effect.fn("GraphRagEngine.scoreEdges")(function* (
   clients: GraphRagClients,
   config: NormalizedGraphRagConfig,
   query: string,
   triples: Triple[],
-): Effect.Effect<Triple[], GraphRagEngineError> {
-  return Effect.gen(function* () {
+) {
     if (triples.length === 0) return [];
 
     if (triples.length <= 500) {
@@ -372,15 +367,13 @@ function scoreEdges(
 
     return result;
   });
-}
 
-function synthesize(
+const synthesize = Effect.fn("GraphRagEngine.synthesize")(function* (
   clients: GraphRagClients,
   query: string,
   edges: Triple[],
   chunkCallback?: ChunkCallback,
-): Effect.Effect<string, GraphRagEngineError> {
-  return Effect.gen(function* () {
+) {
     const context = edges
       .map((triple) => `${termToString(triple.s)} -> ${termToString(triple.p)} -> ${termToString(triple.o)}`)
       .join("\n");
@@ -431,7 +424,6 @@ function synthesize(
 
     return resp.response;
   });
-}
 
 const ScoredEdge = S.Struct({
   id: S.String,