feat(rag): 混合检索融合 — Milvus 向量 + Bleve 全文 + RRF + DashScope rerank

检索从向量单路升级为混合：向量(Milvus) + 全文(Bleve BM25) → RRF 融合 →
可选 rerank(DashScope gte-rerank)。

- rag/bleve.go: Bleve 全文索引(内存,随 ingest 写入;kb 过滤)；ingest 同步写 Milvus+Bleve
- rag/fuse.go: RRF(Reciprocal Rank Fusion, k=60, 按文本去重)融合多路排序
- rag/rerank.go: DashScope gte-rerank 客户端(可选,env 配置,失败降级 RRF)
- rag/rag.go: Search 改混合(向量+全文→RRF→可选rerank→topK)；main 读 RERANK_* env
- 验证: 全模块 build✓ + e2e PASS; live——入库写双索引；查'NATS'→全文精确命中#1+向量
  →RRF NATS 排首(向量=4 全文=1)；接 DashScope gte-rerank(百炼 key 有权限)→relevance
  score 0.19 真重排；retriever 节点端到端→DeepSeek 答 Milvus
- 边界: Neo4j 图路(GraphRAG,需实体抽取)推迟；Bleve 内存索引重启重建；rerank 走 env
  (TODO 同 embedding 搬控制面 kind=rerank)

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

go.work.sum

@@ -1,50 +1,11 @@
-github.com/RoaringBitmap/roaring v1.9.3 h1:t4EbC5qQwnisr5PrP9nt0IRhRTb9gMUgQF4t4S2OByM=
-github.com/RoaringBitmap/roaring v1.9.3/go.mod h1:6AXUsoIEzDTFFQCe1RbGA6uFONMhvejWj5rqITANK90=
-github.com/bits-and-blooms/bitset v1.12.0 h1:U/q1fAF7xXRhFCrhROzIfffYnu+dlS38vCZtmFVPHmA=
-github.com/bits-and-blooms/bitset v1.12.0/go.mod h1:7hO7Gc7Pp1vODcmWvKMRA9BNmbv6a/7QIWpPxHddWR8=
-github.com/blevesearch/bleve/v2 v2.4.2 h1:NooYP1mb3c0StkiY9/xviiq2LGSaE8BQBCc/pirMx0U=
-github.com/blevesearch/bleve_index_api v1.1.10 h1:PDLFhVjrjQWr6jCuU7TwlmByQVCSEURADHdCqVS9+g0=
-github.com/blevesearch/bleve_index_api v1.1.10/go.mod h1:PbcwjIcRmjhGbkS/lJCpfgVSMROV6TRubGGAODaK1W8=
-github.com/blevesearch/geo v0.1.20 h1:paaSpu2Ewh/tn5DKn/FB5SzvH0EWupxHEIwbCk/QPqM=
-github.com/blevesearch/geo v0.1.20/go.mod h1:DVG2QjwHNMFmjo+ZgzrIq2sfCh6rIHzy9d9d0B59I6w=
-github.com/blevesearch/go-faiss v1.0.20 h1:AIkdTQFWuZ5LQmKQSebgMR4RynGNw8ZseJXaan5kvtI=
-github.com/blevesearch/go-faiss v1.0.20/go.mod h1:jrxHrbl42X/RnDPI+wBoZU8joxxuRwedrxqswQ3xfU8=
 github.com/blevesearch/go-metrics v0.0.0-20201227073835-cf1acfcdf475 h1:kDy+zgJFJJoJYBvdfBSiZYBbdsUL0XcjHYWezpQBGPA=
 github.com/blevesearch/go-metrics v0.0.0-20201227073835-cf1acfcdf475/go.mod h1:9eJDeqxJ3E7WnLebQUlPD7ZjSce7AnDb9vjGmMCbD0A=
-github.com/blevesearch/go-porterstemmer v1.0.3 h1:GtmsqID0aZdCSNiY8SkuPJ12pD4jI+DdXTAn4YRcHCo=
-github.com/blevesearch/go-porterstemmer v1.0.3/go.mod h1:angGc5Ht+k2xhJdZi511LtmxuEf0OVpvUUNrwmM1P7M=
 github.com/blevesearch/goleveldb v1.0.1 h1:iAtV2Cu5s0GD1lwUiekkFHe2gTMCCNVj2foPclDLIFI=
 github.com/blevesearch/goleveldb v1.0.1/go.mod h1:WrU8ltZbIp0wAoig/MHbrPCXSOLpe79nz5lv5nqfYrQ=
-github.com/blevesearch/gtreap v0.1.1 h1:2JWigFrzDMR+42WGIN/V2p0cUvn4UP3C4Q5nmaZGW8Y=
-github.com/blevesearch/gtreap v0.1.1/go.mod h1:QaQyDRAT51sotthUWAH4Sj08awFSSWzgYICSZ3w0tYk=
-github.com/blevesearch/mmap-go v1.0.4 h1:OVhDhT5B/M1HNPpYPBKIEJaD0F3Si+CrEKULGCDPWmc=
-github.com/blevesearch/mmap-go v1.0.4/go.mod h1:EWmEAOmdAS9z/pi/+Toxu99DnsbhG1TIxUoRmJw/pSs=
-github.com/blevesearch/scorch_segment_api/v2 v2.2.15 h1:prV17iU/o+A8FiZi9MXmqbagd8I0bCqM7OKUYPbnb5Y=
-github.com/blevesearch/scorch_segment_api/v2 v2.2.15/go.mod h1:db0cmP03bPNadXrCDuVkKLV6ywFSiRgPFT1YVrestBc=
-github.com/blevesearch/segment v0.9.1 h1:+dThDy+Lvgj5JMxhmOVlgFfkUtZV2kw49xax4+jTfSU=
-github.com/blevesearch/segment v0.9.1/go.mod h1:zN21iLm7+GnBHWTao9I+Au/7MBiL8pPFtJBJTsk6kQw=
 github.com/blevesearch/snowball v0.6.1 h1:cDYjn/NCH+wwt2UdehaLpr2e4BwLIjN4V/TdLsL+B5A=
 github.com/blevesearch/snowball v0.6.1/go.mod h1:ZF0IBg5vgpeoUhnMza2v0A/z8m1cWPlwhke08LpNusg=
-github.com/blevesearch/snowballstem v0.9.0 h1:lMQ189YspGP6sXvZQ4WZ+MLawfV8wOmPoD/iWeNXm8s=
-github.com/blevesearch/snowballstem v0.9.0/go.mod h1:PivSj3JMc8WuaFkTSRDW2SlrulNWPl4ABg1tC/hlgLs=
 github.com/blevesearch/stempel v0.2.0 h1:CYzVPaScODMvgE9o+kf6D4RJ/VRomyi9uHF+PtB+Afc=
 github.com/blevesearch/stempel v0.2.0/go.mod h1:wjeTHqQv+nQdbPuJ/YcvOjTInA2EIc6Ks1FoSUzSLvc=
-github.com/blevesearch/upsidedown_store_api v1.0.2 h1:U53Q6YoWEARVLd1OYNc9kvhBMGZzVrdmaozG2MfoB+A=
-github.com/blevesearch/upsidedown_store_api v1.0.2/go.mod h1:M01mh3Gpfy56Ps/UXHjEO/knbqyQ1Oamg8If49gRwrQ=
-github.com/blevesearch/vellum v1.0.10 h1:HGPJDT2bTva12hrHepVT3rOyIKFFF4t7Gf6yMxyMIPI=
-github.com/blevesearch/vellum v1.0.10/go.mod h1:ul1oT0FhSMDIExNjIxHqJoGpVrBpKCdgDQNxfqgJt7k=
-github.com/blevesearch/zapx/v11 v11.3.10 h1:hvjgj9tZ9DeIqBCxKhi70TtSZYMdcFn7gDb71Xo/fvk=
-github.com/blevesearch/zapx/v11 v11.3.10/go.mod h1:0+gW+FaE48fNxoVtMY5ugtNHHof/PxCqh7CnhYdnMzQ=
-github.com/blevesearch/zapx/v12 v12.3.10 h1:yHfj3vXLSYmmsBleJFROXuO08mS3L1qDCdDK81jDl8s=
-github.com/blevesearch/zapx/v12 v12.3.10/go.mod h1:0yeZg6JhaGxITlsS5co73aqPtM04+ycnI6D1v0mhbCs=
-github.com/blevesearch/zapx/v13 v13.3.10 h1:0KY9tuxg06rXxOZHg3DwPJBjniSlqEgVpxIqMGahDE8=
-github.com/blevesearch/zapx/v13 v13.3.10/go.mod h1:w2wjSDQ/WBVeEIvP0fvMJZAzDwqwIEzVPnCPrz93yAk=
-github.com/blevesearch/zapx/v14 v14.3.10 h1:SG6xlsL+W6YjhX5N3aEiL/2tcWh3DO75Bnz77pSwwKU=
-github.com/blevesearch/zapx/v14 v14.3.10/go.mod h1:qqyuR0u230jN1yMmE4FIAuCxmahRQEOehF78m6oTgns=
-github.com/blevesearch/zapx/v15 v15.3.13 h1:6EkfaZiPlAxqXz0neniq35my6S48QI94W/wyhnpDHHQ=
-github.com/blevesearch/zapx/v15 v15.3.13/go.mod h1:Turk/TNRKj9es7ZpKK95PS7f6D44Y7fAFy8F4LXQtGg=
-github.com/blevesearch/zapx/v16 v16.1.5 h1:b0sMcarqNFxuXvjoXsF8WtwVahnxyhEvBSRJi/AUHjU=
-github.com/blevesearch/zapx/v16 v16.1.5/go.mod h1:J4mSF39w1QELc11EWRSBFkPeZuO7r/NPKkHzDCoiaI8=
 github.com/bytedance/sonic v1.12.2/go.mod h1:B8Gt/XvtZ3Fqj+iSKMypzymZxw/FVwgIGKzMzT9r/rk=
 github.com/bytedance/sonic/loader v0.2.0/go.mod h1:ncP89zfokxS5LZrJxl5z0UJcsk4M4yY2JpfqGeCtNLU=
 github.com/bytedance/sonic/loader v0.3.0/go.mod h1:N8A3vUdtUebEY2/VQC0MyhYeKUFosQU6FxH2JmUe6VI=
@@ -53,19 +14,14 @@ github.com/couchbase/ghistogram v0.1.0/go.mod h1:s1Jhy76zqfEecpNWJfWUiKZookAFaiG
 github.com/couchbase/moss v0.2.0 h1:VCYrMzFwEryyhRSeI+/b3tRBSeTpi/8gn5Kf6dxqn+o=
 github.com/couchbase/moss v0.2.0/go.mod h1:9MaHIaRuy9pvLPUJxB8sh8OrLfyDczECVL37grCIubs=
 github.com/creack/pty v1.1.9 h1:uDmaGzcdjhF4i/plgjmEsriH11Y0o7RKapEf/LDaM3w=
-github.com/golang/geo v0.0.0-20210211234256-740aa86cb551 h1:gtexQ/VGyN+VVFRXSFiguSNcXmS6rkKT+X7FdIrTtfo=
-github.com/golang/geo v0.0.0-20210211234256-740aa86cb551/go.mod h1:QZ0nwyI2jOfgRAoBvP+ab5aRr7c9x7lhGEJrKvBwjWI=
-github.com/golang/snappy v0.0.1 h1:Qgr9rKW7uDUkrbSmQeiDsGa8SjGyCOGtuasMWwvp2P4=
-github.com/golang/snappy v0.0.1/go.mod h1:/XxbfmMg8lxefKM7IXC3fBNl/7bRcc72aCRzEWrmP2Q=
 github.com/google/go-cmp v0.6.0 h1:ofyhxvXcZhMsU5ulbFiLKl/XBFqE1GSq7atu8tAmTRI=
 github.com/google/go-cmp v0.6.0/go.mod h1:17dUlkBOakJ0+DkrSSNjCkIjxS6bF9zb3elmeNGIjoY=
 github.com/google/gofuzz v1.0.0 h1:A8PeW59pxE9IoFRqBp37U+mSNaQoZ46F1f0f863XSXw=
+github.com/google/gofuzz v1.2.0/go.mod h1:dBl0BpW6vV/+mYPU4Po3pmUjxk6FQPldtuIdl/M65Eg=
 github.com/inconshreveable/mousetrap v1.1.0 h1:wN+x4NVGpMsO7ErUn/mUI3vEoE6Jt13X2s0bqwp9tc8=
 github.com/inconshreveable/mousetrap v1.1.0/go.mod h1:vpF70FUmC8bwa3OWnCshd2FqLfsEA9PFc4w1p2J65bw=
 github.com/knz/go-libedit v1.10.1 h1:0pHpWtx9vcvC0xGZqEQlQdfSQs7WRlAjuPvk3fOZDCo=
 github.com/kr/pty v1.1.1 h1:VkoXIwSboBpnk99O/KFauAEILuNHv5DVFKZMBN/gUgw=
-github.com/mschoch/smat v0.2.0 h1:8imxQsjDm8yFEAVBe7azKmKSgzSkZXDuKkSq9374khM=
-github.com/mschoch/smat v0.2.0/go.mod h1:kc9mz7DoBKqDyiRL7VZN8KvXQMWeTaVnttLRXOlotKw=
 github.com/neo4j/neo4j-go-driver/v5 v5.24.0 h1:7MAFoB7L6f9heQUo/tJ5EnrrpVzm9ZBHgH8ew03h6Eo=
 github.com/pelletier/go-toml v1.2.0 h1:T5zMGML61Wp+FlcbWjRDT7yAxhJNAiPPLOFECq181zc=
 github.com/spf13/cobra v1.7.0 h1:hyqWnYt1ZQShIddO5kBpj3vu05/++x6tJ6dg8EC572I=
@@ -78,8 +34,6 @@ github.com/x448/float16 v0.8.4 h1:qLwI1I70+NjRFUR3zs1JPUCgaCXSh3SW62uAKT1mSBM=
 github.com/x448/float16 v0.8.4/go.mod h1:14CWIYCyZA/cWjXOioeEpHeN/83MdbZDRQHoFcYsOfg=
 github.com/yuin/goldmark v1.4.13 h1:fVcFKWvrslecOb/tg+Cc05dkeYx540o0FuFt3nUVDoE=
 github.com/yuin/goldmark v1.4.13/go.mod h1:6yULJ656Px+3vBD8DxQVa3kxgyrAnzto9xy5taEt/CY=
-go.etcd.io/bbolt v1.3.7 h1:j+zJOnnEjF/kyHlDDgGnVL/AIqIJPq8UoB2GSNfkUfQ=
-go.etcd.io/bbolt v1.3.7/go.mod h1:N9Mkw9X8x5fupy0IKsmuqVtoGDyxsaDlbk4Rd05IAQw=
 go.uber.org/automaxprocs v1.5.3 h1:kWazyxZUrS3Gs4qUpbwo5kEIMGe/DAvi5Z4tl2NW4j8=
 go.uber.org/automaxprocs v1.5.3/go.mod h1:eRbA25aqJrxAbsLO0xy5jVwPt7FQnRgjW+efnwa1WM0=
 golang.org/x/crypto v0.23.0/go.mod h1:CKFgDieR+mRhux2Lsu27y0fO304Db0wZe70UKqHu0v8=

sundynix-mcp-go/cmd/server/main.go

@@ -27,6 +27,9 @@ func main() {
 	embBase := envOr("EMBED_BASE_URL", "") // OpenAI 兼容 embeddings 端点（空=向量检索降级）
 	embKey := envOr("EMBED_API_KEY", "")
 	embModel := envOr("EMBED_MODEL", "")
+	rerankBase := envOr("RERANK_BASE_URL", "") // DashScope 文本重排端点（空=不启用 rerank）
+	rerankKey := envOr("RERANK_API_KEY", "")
+	rerankModel := envOr("RERANK_MODEL", "")
 
 	b, err := sharedbus.Connect(natsURL)
 	if err != nil {
@@ -44,7 +47,8 @@ func main() {
 	ctx, stop := signal.NotifyContext(context.Background(), syscall.SIGINT, syscall.SIGTERM)
 	defer stop()
 
-	ragEngine := rag.Open(ctx, milvusAddr, embBase, embKey, embModel) // RAG 核心链：embedding(env 初值) + Milvus
+	// RAG 核心链：embedding(env 初值) + Milvus(向量) + Bleve(全文) + 可选 rerank
+	ragEngine := rag.Open(ctx, milvusAddr, embBase, embKey, embModel, rerankBase, rerankKey, rerankModel)
 	defer ragEngine.Close()
 
 	// 配置控制面：启动取激活 embedding 配置 + 订阅热更新（覆盖 env，持久化由 Gateway 管）。

sundynix-mcp-go/go.mod

@@ -3,6 +3,7 @@ module github.com/sundynix/sundynix-mcp-go
 go 1.24
 
 require (
+	github.com/blevesearch/bleve/v2 v2.4.2
 	github.com/milvus-io/milvus-sdk-go/v2 v2.4.1
 	github.com/redis/go-redis/v9 v9.20.0
 	github.com/sundynix/sundynix-shared v0.0.0
@@ -11,13 +12,34 @@ require (
 )
 
 require (
+	github.com/RoaringBitmap/roaring v1.9.3 // indirect
+	github.com/bits-and-blooms/bitset v1.12.0 // indirect
+	github.com/blevesearch/bleve_index_api v1.1.10 // indirect
+	github.com/blevesearch/geo v0.1.20 // indirect
+	github.com/blevesearch/go-faiss v1.0.20 // indirect
+	github.com/blevesearch/go-porterstemmer v1.0.3 // indirect
+	github.com/blevesearch/gtreap v0.1.1 // indirect
+	github.com/blevesearch/mmap-go v1.0.4 // indirect
+	github.com/blevesearch/scorch_segment_api/v2 v2.2.15 // indirect
+	github.com/blevesearch/segment v0.9.1 // indirect
+	github.com/blevesearch/snowballstem v0.9.0 // indirect
+	github.com/blevesearch/upsidedown_store_api v1.0.2 // indirect
+	github.com/blevesearch/vellum v1.0.10 // indirect
+	github.com/blevesearch/zapx/v11 v11.3.10 // indirect
+	github.com/blevesearch/zapx/v12 v12.3.10 // indirect
+	github.com/blevesearch/zapx/v13 v13.3.10 // indirect
+	github.com/blevesearch/zapx/v14 v14.3.10 // indirect
+	github.com/blevesearch/zapx/v15 v15.3.13 // indirect
+	github.com/blevesearch/zapx/v16 v16.1.5 // indirect
 	github.com/cespare/xxhash/v2 v2.3.0 // indirect
 	github.com/cockroachdb/errors v1.9.1 // indirect
 	github.com/cockroachdb/logtags v0.0.0-20211118104740-dabe8e521a4f // indirect
 	github.com/cockroachdb/redact v1.1.3 // indirect
 	github.com/getsentry/sentry-go v0.12.0 // indirect
 	github.com/gogo/protobuf v1.3.2 // indirect
+	github.com/golang/geo v0.0.0-20210211234256-740aa86cb551 // indirect
 	github.com/golang/protobuf v1.5.2 // indirect
+	github.com/golang/snappy v0.0.1 // indirect
 	github.com/grpc-ecosystem/go-grpc-middleware v1.3.0 // indirect
 	github.com/jackc/pgpassfile v1.0.0 // indirect
 	github.com/jackc/pgservicefile v0.0.0-20240606120523-5a60cdf6a761 // indirect
@@ -25,10 +47,14 @@ require (
 	github.com/jackc/puddle/v2 v2.2.2 // indirect
 	github.com/jinzhu/inflection v1.0.0 // indirect
 	github.com/jinzhu/now v1.1.5 // indirect
+	github.com/json-iterator/go v1.1.9 // indirect
 	github.com/klauspost/compress v1.17.9 // indirect
 	github.com/kr/pretty v0.3.0 // indirect
 	github.com/kr/text v0.2.0 // indirect
 	github.com/milvus-io/milvus-proto/go-api/v2 v2.4.3 // indirect
+	github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd // indirect
+	github.com/modern-go/reflect2 v1.0.1 // indirect
+	github.com/mschoch/smat v0.2.0 // indirect
 	github.com/nats-io/nats.go v1.37.0 // indirect
 	github.com/nats-io/nkeys v0.4.7 // indirect
 	github.com/nats-io/nuid v1.0.1 // indirect
@@ -37,6 +63,7 @@ require (
 	github.com/tidwall/gjson v1.14.4 // indirect
 	github.com/tidwall/match v1.1.1 // indirect
 	github.com/tidwall/pretty v1.2.0 // indirect
+	go.etcd.io/bbolt v1.3.7 // indirect
 	go.uber.org/atomic v1.11.0 // indirect
 	golang.org/x/crypto v0.31.0 // indirect
 	golang.org/x/net v0.21.0 // indirect

sundynix-mcp-go/go.sum

@@ -5,11 +5,51 @@ github.com/BurntSushi/toml v0.3.1/go.mod h1:xHWCNGjB5oqiDr8zfno3MHue2Ht5sIBksp03
 github.com/CloudyKit/fastprinter v0.0.0-20200109182630-33d98a066a53/go.mod h1:+3IMCy2vIlbG1XG/0ggNQv0SvxCAIpPM5b1nCz56Xno=
 github.com/CloudyKit/jet/v3 v3.0.0/go.mod h1:HKQPgSJmdK8hdoAbKUUWajkHyHo4RaU5rMdUywE7VMo=
 github.com/Joker/hpp v1.0.0/go.mod h1:8x5n+M1Hp5hC0g8okX3sR3vFQwynaX/UgSOM9MeBKzY=
+github.com/RoaringBitmap/roaring v1.9.3 h1:t4EbC5qQwnisr5PrP9nt0IRhRTb9gMUgQF4t4S2OByM=
+github.com/RoaringBitmap/roaring v1.9.3/go.mod h1:6AXUsoIEzDTFFQCe1RbGA6uFONMhvejWj5rqITANK90=
 github.com/Shopify/goreferrer v0.0.0-20181106222321-ec9c9a553398/go.mod h1:a1uqRtAwp2Xwc6WNPJEufxJ7fx3npB4UV/JOLmbu5I0=
 github.com/ajg/form v1.5.1/go.mod h1:uL1WgH+h2mgNtvBq0339dVnzXdBETtL2LeUXaIv25UY=
 github.com/antihax/optional v1.0.0/go.mod h1:uupD/76wgC+ih3iEmQUL+0Ugr19nfwCT1kdvxnR2qWY=
 github.com/armon/consul-api v0.0.0-20180202201655-eb2c6b5be1b6/go.mod h1:grANhF5doyWs3UAsr3K4I6qtAmlQcZDesFNEHPZAzj8=
 github.com/aymerick/raymond v2.0.3-0.20180322193309-b565731e1464+incompatible/go.mod h1:osfaiScAUVup+UC9Nfq76eWqDhXlp+4UYaA8uhTBO6g=
+github.com/bits-and-blooms/bitset v1.12.0 h1:U/q1fAF7xXRhFCrhROzIfffYnu+dlS38vCZtmFVPHmA=
+github.com/bits-and-blooms/bitset v1.12.0/go.mod h1:7hO7Gc7Pp1vODcmWvKMRA9BNmbv6a/7QIWpPxHddWR8=
+github.com/blevesearch/bleve/v2 v2.4.2 h1:NooYP1mb3c0StkiY9/xviiq2LGSaE8BQBCc/pirMx0U=
+github.com/blevesearch/bleve/v2 v2.4.2/go.mod h1:ATNKj7Yl2oJv/lGuF4kx39bST2dveX6w0th2FFYLkc8=
+github.com/blevesearch/bleve_index_api v1.1.10 h1:PDLFhVjrjQWr6jCuU7TwlmByQVCSEURADHdCqVS9+g0=
+github.com/blevesearch/bleve_index_api v1.1.10/go.mod h1:PbcwjIcRmjhGbkS/lJCpfgVSMROV6TRubGGAODaK1W8=
+github.com/blevesearch/geo v0.1.20 h1:paaSpu2Ewh/tn5DKn/FB5SzvH0EWupxHEIwbCk/QPqM=
+github.com/blevesearch/geo v0.1.20/go.mod h1:DVG2QjwHNMFmjo+ZgzrIq2sfCh6rIHzy9d9d0B59I6w=
+github.com/blevesearch/go-faiss v1.0.20 h1:AIkdTQFWuZ5LQmKQSebgMR4RynGNw8ZseJXaan5kvtI=
+github.com/blevesearch/go-faiss v1.0.20/go.mod h1:jrxHrbl42X/RnDPI+wBoZU8joxxuRwedrxqswQ3xfU8=
+github.com/blevesearch/go-porterstemmer v1.0.3 h1:GtmsqID0aZdCSNiY8SkuPJ12pD4jI+DdXTAn4YRcHCo=
+github.com/blevesearch/go-porterstemmer v1.0.3/go.mod h1:angGc5Ht+k2xhJdZi511LtmxuEf0OVpvUUNrwmM1P7M=
+github.com/blevesearch/gtreap v0.1.1 h1:2JWigFrzDMR+42WGIN/V2p0cUvn4UP3C4Q5nmaZGW8Y=
+github.com/blevesearch/gtreap v0.1.1/go.mod h1:QaQyDRAT51sotthUWAH4Sj08awFSSWzgYICSZ3w0tYk=
+github.com/blevesearch/mmap-go v1.0.4 h1:OVhDhT5B/M1HNPpYPBKIEJaD0F3Si+CrEKULGCDPWmc=
+github.com/blevesearch/mmap-go v1.0.4/go.mod h1:EWmEAOmdAS9z/pi/+Toxu99DnsbhG1TIxUoRmJw/pSs=
+github.com/blevesearch/scorch_segment_api/v2 v2.2.15 h1:prV17iU/o+A8FiZi9MXmqbagd8I0bCqM7OKUYPbnb5Y=
+github.com/blevesearch/scorch_segment_api/v2 v2.2.15/go.mod h1:db0cmP03bPNadXrCDuVkKLV6ywFSiRgPFT1YVrestBc=
+github.com/blevesearch/segment v0.9.1 h1:+dThDy+Lvgj5JMxhmOVlgFfkUtZV2kw49xax4+jTfSU=
+github.com/blevesearch/segment v0.9.1/go.mod h1:zN21iLm7+GnBHWTao9I+Au/7MBiL8pPFtJBJTsk6kQw=
+github.com/blevesearch/snowballstem v0.9.0 h1:lMQ189YspGP6sXvZQ4WZ+MLawfV8wOmPoD/iWeNXm8s=
+github.com/blevesearch/snowballstem v0.9.0/go.mod h1:PivSj3JMc8WuaFkTSRDW2SlrulNWPl4ABg1tC/hlgLs=
+github.com/blevesearch/upsidedown_store_api v1.0.2 h1:U53Q6YoWEARVLd1OYNc9kvhBMGZzVrdmaozG2MfoB+A=
+github.com/blevesearch/upsidedown_store_api v1.0.2/go.mod h1:M01mh3Gpfy56Ps/UXHjEO/knbqyQ1Oamg8If49gRwrQ=
+github.com/blevesearch/vellum v1.0.10 h1:HGPJDT2bTva12hrHepVT3rOyIKFFF4t7Gf6yMxyMIPI=
+github.com/blevesearch/vellum v1.0.10/go.mod h1:ul1oT0FhSMDIExNjIxHqJoGpVrBpKCdgDQNxfqgJt7k=
+github.com/blevesearch/zapx/v11 v11.3.10 h1:hvjgj9tZ9DeIqBCxKhi70TtSZYMdcFn7gDb71Xo/fvk=
+github.com/blevesearch/zapx/v11 v11.3.10/go.mod h1:0+gW+FaE48fNxoVtMY5ugtNHHof/PxCqh7CnhYdnMzQ=
+github.com/blevesearch/zapx/v12 v12.3.10 h1:yHfj3vXLSYmmsBleJFROXuO08mS3L1qDCdDK81jDl8s=
+github.com/blevesearch/zapx/v12 v12.3.10/go.mod h1:0yeZg6JhaGxITlsS5co73aqPtM04+ycnI6D1v0mhbCs=
+github.com/blevesearch/zapx/v13 v13.3.10 h1:0KY9tuxg06rXxOZHg3DwPJBjniSlqEgVpxIqMGahDE8=
+github.com/blevesearch/zapx/v13 v13.3.10/go.mod h1:w2wjSDQ/WBVeEIvP0fvMJZAzDwqwIEzVPnCPrz93yAk=
+github.com/blevesearch/zapx/v14 v14.3.10 h1:SG6xlsL+W6YjhX5N3aEiL/2tcWh3DO75Bnz77pSwwKU=
+github.com/blevesearch/zapx/v14 v14.3.10/go.mod h1:qqyuR0u230jN1yMmE4FIAuCxmahRQEOehF78m6oTgns=
+github.com/blevesearch/zapx/v15 v15.3.13 h1:6EkfaZiPlAxqXz0neniq35my6S48QI94W/wyhnpDHHQ=
+github.com/blevesearch/zapx/v15 v15.3.13/go.mod h1:Turk/TNRKj9es7ZpKK95PS7f6D44Y7fAFy8F4LXQtGg=
+github.com/blevesearch/zapx/v16 v16.1.5 h1:b0sMcarqNFxuXvjoXsF8WtwVahnxyhEvBSRJi/AUHjU=
+github.com/blevesearch/zapx/v16 v16.1.5/go.mod h1:J4mSF39w1QELc11EWRSBFkPeZuO7r/NPKkHzDCoiaI8=
 github.com/bsm/ginkgo/v2 v2.12.0 h1:Ny8MWAHyOepLGlLKYmXG4IEkioBysk6GpaRTLC8zwWs=
 github.com/bsm/ginkgo/v2 v2.12.0/go.mod h1:SwYbGRRDovPVboqFv0tPTcG1sN61LM1Z4ARdbAV9g4c=
 github.com/bsm/gomega v1.27.10 h1:yeMWxP2pV2fG3FgAODIY8EiRE3dy0aeFYt4l7wh6yKA=
@@ -81,6 +121,8 @@ github.com/gogo/protobuf v1.3.2 h1:Ov1cvc58UF3b5XjBnZv7+opcTcQFZebYjWzi34vdm4Q=
 github.com/gogo/protobuf v1.3.2/go.mod h1:P1XiOD3dCwIKUDQYPy72D8LYyHL2YPYrpS2s69NZV8Q=
 github.com/gogo/status v1.1.0/go.mod h1:BFv9nrluPLmrS0EmGVvLaPNmRosr9KapBYd5/hpY1WM=
 github.com/golang-jwt/jwt v3.2.2+incompatible/go.mod h1:8pz2t5EyA70fFQQSrl6XZXzqecmYZeUEB8OUGHkxJ+I=
+github.com/golang/geo v0.0.0-20210211234256-740aa86cb551 h1:gtexQ/VGyN+VVFRXSFiguSNcXmS6rkKT+X7FdIrTtfo=
+github.com/golang/geo v0.0.0-20210211234256-740aa86cb551/go.mod h1:QZ0nwyI2jOfgRAoBvP+ab5aRr7c9x7lhGEJrKvBwjWI=
 github.com/golang/glog v0.0.0-20160126235308-23def4e6c14b/go.mod h1:SBH7ygxi8pfUlaOkMMuAQtPIUF8ecWP5IEl/CR7VP2Q=
 github.com/golang/mock v1.1.1/go.mod h1:oTYuIxOrZwtPieC+H1uAHpcLFnEyAGVDL/k47Jfbm0A=
 github.com/golang/protobuf v1.2.0/go.mod h1:6lQm79b+lXiMfvg/cZm0SGofjICqVBUtrP5yJMmIC1U=
@@ -98,6 +140,8 @@ github.com/golang/protobuf v1.4.3/go.mod h1:oDoupMAO8OvCJWAcko0GGGIgR6R6ocIYbsSw
 github.com/golang/protobuf v1.5.0/go.mod h1:FsONVRAS9T7sI+LIUmWTfcYkHO4aIWwzhcaSAoJOfIk=
 github.com/golang/protobuf v1.5.2 h1:ROPKBNFfQgOUMifHyP+KYbvpjbdoFNs+aK7DXlji0Tw=
 github.com/golang/protobuf v1.5.2/go.mod h1:XVQd3VNwM+JqD3oG2Ue2ip4fOMUkwXdXDdiuN0vRsmY=
+github.com/golang/snappy v0.0.1 h1:Qgr9rKW7uDUkrbSmQeiDsGa8SjGyCOGtuasMWwvp2P4=
+github.com/golang/snappy v0.0.1/go.mod h1:/XxbfmMg8lxefKM7IXC3fBNl/7bRcc72aCRzEWrmP2Q=
 github.com/gomodule/redigo v1.7.1-0.20190724094224-574c33c3df38/go.mod h1:B4C85qUVwatsJoIUNIfCRsp7qO0iAmpGFZ4EELWSbC4=
 github.com/google/go-cmp v0.2.0/go.mod h1:oXzfMopK8JAjlY9xF4vHSVASa0yLyX7SntLO5aqRK0M=
 github.com/google/go-cmp v0.3.0/go.mod h1:8QqcDgzrUqlUb/G2PQTWiueGozuR1884gddMywk6iLU=
@@ -139,6 +183,7 @@ github.com/jinzhu/inflection v1.0.0/go.mod h1:h+uFLlag+Qp1Va5pdKtLDYj+kHp5pxUVkr
 github.com/jinzhu/now v1.1.5 h1:/o9tlHleP7gOFmsnYNz3RGnqzefHA47wQpKrrdTIwXQ=
 github.com/jinzhu/now v1.1.5/go.mod h1:d3SSVoowX0Lcu0IBviAWJpolVfI5UJVZZ7cO71lE/z8=
 github.com/json-iterator/go v1.1.6/go.mod h1:+SdeFBvtyEkXs7REEP0seUULqWtbJapLOCVDaaPEHmU=
+github.com/json-iterator/go v1.1.9 h1:9yzud/Ht36ygwatGx56VwCZtlI/2AD15T1X2sjSuGns=
 github.com/json-iterator/go v1.1.9/go.mod h1:KdQUCv79m/52Kvf8AW2vK1V8akMuk1QjK/uOdHXbAo4=
 github.com/jtolds/gls v4.20.0+incompatible/go.mod h1:QJZ7F/aHp+rZTRtaJ1ow/lLfFfVYBRgL+9YlvaHOwJU=
 github.com/k0kubun/colorstring v0.0.0-20150214042306-9440f1994b88/go.mod h1:3w7q1U84EfirKl04SVQ/s7nPm1ZPhiXd34z40TNz36k=
@@ -189,10 +234,14 @@ github.com/minio/highwayhash v1.0.3/go.mod h1:GGYsuwP/fPD6Y9hMiXuapVvlIUEhFhMTh0
 github.com/mitchellh/go-homedir v1.1.0/go.mod h1:SfyaCUpYCn1Vlf4IUYiD9fPX4A5wJrkLzIz1N1q0pr0=
 github.com/mitchellh/mapstructure v1.1.2/go.mod h1:FVVH3fgwuzCH5S8UJGiWEs2h04kUh9fWfEaFds41c1Y=
 github.com/modern-go/concurrent v0.0.0-20180228061459-e0a39a4cb421/go.mod h1:6dJC0mAP4ikYIbvyc7fijjWJddQyLn8Ig3JB5CqoB9Q=
+github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd h1:TRLaZ9cD/w8PVh93nsPXa1VrQ6jlwL5oN8l14QlcNfg=
 github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd/go.mod h1:6dJC0mAP4ikYIbvyc7fijjWJddQyLn8Ig3JB5CqoB9Q=
 github.com/modern-go/reflect2 v0.0.0-20180701023420-4b7aa43c6742/go.mod h1:bx2lNnkwVCuqBIxFjflWJWanXIb3RllmbCylyMrvgv0=
+github.com/modern-go/reflect2 v1.0.1 h1:9f412s+6RmYXLWZSEzVVgPGK7C2PphHj5RJrvfx9AWI=
 github.com/modern-go/reflect2 v1.0.1/go.mod h1:bx2lNnkwVCuqBIxFjflWJWanXIb3RllmbCylyMrvgv0=
 github.com/moul/http2curl v1.0.0/go.mod h1:8UbvGypXm98wA/IqH45anm5Y2Z6ep6O31QGOAZ3H0fQ=
+github.com/mschoch/smat v0.2.0 h1:8imxQsjDm8yFEAVBe7azKmKSgzSkZXDuKkSq9374khM=
+github.com/mschoch/smat v0.2.0/go.mod h1:kc9mz7DoBKqDyiRL7VZN8KvXQMWeTaVnttLRXOlotKw=
 github.com/nats-io/jwt v0.3.0 h1:xdnzwFETV++jNc4W1mw//qFyJGb2ABOombmZJQS4+Qo=
 github.com/nats-io/jwt v0.3.0/go.mod h1:fRYCDE99xlTsqUzISS1Bi75UBJ6ljOJQOAAu5VglpSg=
 github.com/nats-io/jwt/v2 v2.5.8 h1:uvdSzwWiEGWGXf+0Q+70qv6AQdvcvxrv9hPM0RiPamE=
@@ -281,6 +330,8 @@ github.com/yuin/goldmark v1.2.1/go.mod h1:3hX8gzYuyVAZsxl0MRgGTJEmQBFcNTphYh9dec
 github.com/yuin/goldmark v1.3.5/go.mod h1:mwnBkeHKe2W/ZEtQ+71ViKU8L12m81fl3OWwC1Zlc8k=
 github.com/zeebo/xxh3 v1.1.0 h1:s7DLGDK45Dyfg7++yxI0khrfwq9661w9EN78eP/UZVs=
 github.com/zeebo/xxh3 v1.1.0/go.mod h1:IisAie1LELR4xhVinxWS5+zf1lA4p0MW4T+w+W07F5s=
+go.etcd.io/bbolt v1.3.7 h1:j+zJOnnEjF/kyHlDDgGnVL/AIqIJPq8UoB2GSNfkUfQ=
+go.etcd.io/bbolt v1.3.7/go.mod h1:N9Mkw9X8x5fupy0IKsmuqVtoGDyxsaDlbk4Rd05IAQw=
 go.opentelemetry.io/proto/otlp v0.7.0/go.mod h1:PqfVotwruBrMGOCsRd/89rSnXhoiJIqeYNgFYFoEGnI=
 go.uber.org/atomic v1.4.0/go.mod h1:gD2HeocX3+yG+ygLZcrzQJaqmWj9AIm7n08wl/qW/PE=
 go.uber.org/atomic v1.11.0 h1:ZvwS0R+56ePWxUNi+Atn9dWONBPp/AUETXlHW0DxSjE=
@@ -363,6 +414,7 @@ golang.org/x/sys v0.0.0-20210630005230-0f9fa26af87c/go.mod h1:oPkhp1MJrh7nUepCBc
 golang.org/x/sys v0.0.0-20210927094055-39ccf1dd6fa6/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.0.0-20211007075335-d3039528d8ac/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.0.0-20220209214540-3681064d5158/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.0.0-20220520151302-bc2c85ada10a/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.30.0 h1:QjkSwP/36a20jFYWkSue1YwXzLmsV5Gfq7Eiy72C1uc=
 golang.org/x/sys v0.30.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
 golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo=

sundynix-mcp-go/internal/rag/bleve.go

@@ -0,0 +1,78 @@
+package rag
+
+import (
+	"fmt"
+	"hash/fnv"
+	"log"
+
+	"github.com/blevesearch/bleve/v2"
+	"github.com/blevesearch/bleve/v2/search/query"
+)
+
+// bleveStore 是全文（BM25）检索路。内存索引：随 ingest 写入，进程重启重建。
+// 真实生产应落盘(bleve.New(path,...))；此处内存优先求简。
+type bleveStore struct {
+	idx bleve.Index
+}
+
+func openBleve() *bleveStore {
+	idx, err := bleve.NewMemOnly(bleve.NewIndexMapping())
+	if err != nil {
+		log.Printf("[rag] bleve 初始化失败，全文路降级: %v", err)
+		return &bleveStore{}
+	}
+	return &bleveStore{idx: idx}
+}
+
+func (b *bleveStore) ready() bool { return b != nil && b.idx != nil }
+
+// index 把 (kb, texts) 写入全文索引（按 kb+文本哈希做幂等 ID）。
+func (b *bleveStore) index(kb string, texts []string) error {
+	if !b.ready() {
+		return nil
+	}
+	batch := b.idx.NewBatch()
+	for _, t := range texts {
+		id := fmt.Sprintf("%s:%x", kb, fnvHash(t))
+		if err := batch.Index(id, map[string]any{"text": t, "kb": kb}); err != nil {
+			return err
+		}
+	}
+	return b.idx.Batch(batch)
+}
+
+// search 全文检索（可按 kb 过滤），返回 BM25 排序的命中。
+func (b *bleveStore) search(kb, q string, topK int) []Hit {
+	if !b.ready() || q == "" {
+		return nil
+	}
+	mq := bleve.NewMatchQuery(q)
+	mq.SetField("text")
+	var qy query.Query = mq
+	if kb != "" {
+		tq := bleve.NewTermQuery(kb)
+		tq.SetField("kb")
+		qy = bleve.NewConjunctionQuery(mq, tq)
+	}
+	req := bleve.NewSearchRequest(qy)
+	req.Size = topK
+	req.Fields = []string{"text"}
+	res, err := b.idx.Search(req)
+	if err != nil {
+		return nil
+	}
+	var hits []Hit
+	for _, h := range res.Hits {
+		text, _ := h.Fields["text"].(string)
+		if text != "" {
+			hits = append(hits, Hit{Text: text, Score: float32(h.Score)})
+		}
+	}
+	return hits
+}
+
+func fnvHash(s string) uint64 {
+	h := fnv.New64a()
+	_, _ = h.Write([]byte(s))
+	return h.Sum64()
+}

sundynix-mcp-go/internal/rag/fuse.go

@@ -0,0 +1,26 @@
+package rag
+
+import "sort"
+
+// rrfK 是 RRF 的平滑常数（业界常用 60）。
+const rrfK = 60.0
+
+// rrf 用 Reciprocal Rank Fusion 融合多路检索的排序列表，按文本去重。
+// 每路对一个文档的贡献 = 1/(k + 该路中的名次)；累加后重排。
+func rrf(lists [][]Hit, topK int) []Hit {
+	score := map[string]float64{}
+	for _, list := range lists {
+		for rank, h := range list {
+			score[h.Text] += 1.0 / (rrfK + float64(rank+1))
+		}
+	}
+	fused := make([]Hit, 0, len(score))
+	for text, s := range score {
+		fused = append(fused, Hit{Text: text, Score: float32(s)})
+	}
+	sort.Slice(fused, func(i, j int) bool { return fused[i].Score > fused[j].Score })
+	if topK > 0 && len(fused) > topK {
+		fused = fused[:topK]
+	}
+	return fused
+}

sundynix-mcp-go/internal/rag/rag.go

@@ -10,11 +10,14 @@ import (
 	"sync"
 )
 
-// Engine 聚合 embedding 与 Milvus，对外提供入库/检索。embedding 可热更新（控制面下发）。
+// Engine 聚合 embedding + Milvus(向量) + Bleve(全文) + RRF 融合 + 可选 rerank。
+// embedding 可热更新（控制面下发）。
 type Engine struct {
 	mu     sync.RWMutex
 	emb    *embedClient
 	mv     *milvusStore
+	bleve  *bleveStore
+	rerank *rerankClient
 }
 
 // SetEmbedding 热更新 embedding 配置（控制面变更时调用）。空配置=关闭向量检索。
@@ -36,8 +39,12 @@ func (e *Engine) embed() *embedClient {
 }
 
 // Open 建立 RAG 引擎。embedding 未配 / Milvus 连不上 → 降级（检索返回空，不阻断工具服务）。
-func Open(ctx context.Context, milvusAddr, embBase, embKey, embModel string) *Engine {
-	e := &Engine{}
+// rerank* 为空则不启用重排（融合结果直接返回）。
+func Open(ctx context.Context, milvusAddr, embBase, embKey, embModel, rerankBase, rerankKey, rerankModel string) *Engine {
+	e := &Engine{bleve: openBleve(), rerank: newRerankClient(rerankBase, rerankKey, rerankModel)}
+	if e.rerank.ready() {
+		log.Printf("[rag] rerank: %s model=%s", rerankBase, rerankModel)
+	}
 	if embBase != "" && embModel != "" {
 		e.SetEmbedding(embBase, embKey, embModel) // env 初值（控制面会覆盖）
 	} else {
@@ -74,10 +81,11 @@ func (e *Engine) Ingest(ctx context.Context, kb, text string) (int, error) {
 	if err := e.mv.insert(ctx, kb, chunks, vecs); err != nil {
 		return 0, err
 	}
+	_ = e.bleve.index(kb, chunks) // 同步写全文索引（失败不阻断向量入库）
 	return len(chunks), nil
 }
 
-// Search 向量化查询 → Milvus topK 检索。降级时返回空。
+// Search 混合检索：Milvus(向量) + Bleve(全文) → RRF 融合 → 可选 rerank → topK。降级时返回空。
 func (e *Engine) Search(ctx context.Context, kb, query string, topK int) ([]Hit, error) {
 	if !e.Ready() {
 		return nil, nil
@@ -85,11 +93,32 @@ func (e *Engine) Search(ctx context.Context, kb, query string, topK int) ([]Hit,
 	if topK <= 0 {
 		topK = 5
 	}
+	fanout := topK * 3
+
+	// 向量路
 	vecs, err := e.embed().Embed(ctx, []string{query})
 	if err != nil || len(vecs) == 0 {
 		return nil, err
 	}
-	return e.mv.search(ctx, kb, vecs[0], topK)
+	vecHits, _ := e.mv.search(ctx, kb, vecs[0], fanout)
+	// 全文路
+	ftHits := e.bleve.search(kb, query, fanout)
+	// RRF 融合（按文本去重）
+	cand := rrf([][]Hit{vecHits, ftHits}, fanout)
+	log.Printf("[rag] hybrid: 向量=%d 全文=%d → 融合=%d", len(vecHits), len(ftHits), len(cand))
+
+	// 可选 rerank：对融合候选重排取 topK
+	if e.rerank.ready() && len(cand) > 1 {
+		if rr, rerr := e.rerank.rerank(ctx, query, cand, topK); rerr == nil {
+			return rr, nil
+		} else {
+			log.Printf("[rag] rerank 降级（用 RRF 结果）: %v", rerr)
+		}
+	}
+	if len(cand) > topK {
+		cand = cand[:topK]
+	}
+	return cand, nil
 }
 
 func (e *Engine) Close() {

sundynix-mcp-go/internal/rag/rerank.go

@@ -0,0 +1,85 @@
+package rag
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"sort"
+	"time"
+)
+
+// rerankClient 调用 DashScope 文本重排（gte-rerank）。可选阶段：未配则跳过。
+// DashScope 原生格式（非 OpenAI 兼容）：
+//
+//	POST {baseURL}  {model, input:{query, documents}, parameters:{top_n, return_documents:false}}
+//	resp {output:{results:[{index, relevance_score}]}}
+type rerankClient struct {
+	baseURL string
+	apiKey  string
+	model   string
+	hc      *http.Client
+}
+
+func newRerankClient(baseURL, apiKey, model string) *rerankClient {
+	if baseURL == "" || model == "" {
+		return nil
+	}
+	return &rerankClient{baseURL: baseURL, apiKey: apiKey, model: model, hc: &http.Client{Timeout: 20 * time.Second}}
+}
+
+func (r *rerankClient) ready() bool { return r != nil && r.baseURL != "" }
+
+// rerank 用重排模型对候选重新打分排序，返回前 topN。出错时返回原序（降级）。
+func (r *rerankClient) rerank(ctx context.Context, query string, hits []Hit, topN int) ([]Hit, error) {
+	docs := make([]string, len(hits))
+	for i, h := range hits {
+		docs[i] = h.Text
+	}
+	body, _ := json.Marshal(map[string]any{
+		"model": r.model,
+		"input": map[string]any{"query": query, "documents": docs},
+		"parameters": map[string]any{"top_n": topN, "return_documents": false},
+	})
+	req, err := http.NewRequestWithContext(ctx, http.MethodPost, r.baseURL, bytes.NewReader(body))
+	if err != nil {
+		return hits, err
+	}
+	req.Header.Set("Content-Type", "application/json")
+	if r.apiKey != "" {
+		req.Header.Set("Authorization", "Bearer "+r.apiKey)
+	}
+	resp, err := r.hc.Do(req)
+	if err != nil {
+		return hits, err
+	}
+	defer resp.Body.Close()
+	if resp.StatusCode >= 400 {
+		buf := new(bytes.Buffer)
+		_, _ = buf.ReadFrom(resp.Body)
+		return hits, fmt.Errorf("rerank http %d: %s", resp.StatusCode, buf.String())
+	}
+	var out struct {
+		Output struct {
+			Results []struct {
+				Index          int     `json:"index"`
+				RelevanceScore float32 `json:"relevance_score"`
+			} `json:"results"`
+		} `json:"output"`
+	}
+	if err := json.NewDecoder(resp.Body).Decode(&out); err != nil {
+		return hits, err
+	}
+	res := make([]Hit, 0, len(out.Output.Results))
+	for _, rr := range out.Output.Results {
+		if rr.Index >= 0 && rr.Index < len(hits) {
+			res = append(res, Hit{Text: hits[rr.Index].Text, Score: rr.RelevanceScore})
+		}
+	}
+	if len(res) == 0 {
+		return hits, nil
+	}
+	sort.Slice(res, func(i, j int) bool { return res[i].Score > res[j].Score })
+	return res, nil
+}