%%{init: {"theme":"base","themeVariables":{"primaryColor":"#ffffff","primaryTextColor":"#000000","primaryBorderColor":"#000000","lineColor":"#000000","secondaryColor":"#ffffff","tertiaryColor":"#ffffff","clusterBkg":"#ffffff","clusterBorder":"#000000","edgeLabelBackground":"#ffffff"},"flowchart":{"curve":"linear","nodeSpacing":75,"rankSpacing":70}}}%%
flowchart TB
%% Concept-only diagram (product value; no deployment/framework/datastore details)
classDef mono fill:#ffffff,stroke:#000000,color:#000000,stroke-width:1px;
subgraph Inputs[" "]
direction LR
subgraph Query["Agent-native interface"]
direction TB
Users["Agents + humans"]:::mono
subgraph Tooling["Tool call"]
direction LR
Criteria["Routing constraints<br/>domain, privacy, citations,<br/>freshness, auth, limits"]:::mono
Tools["MCP tools<br/>rag_find_servers<br/>rag_get_server<br/>rag_list_categories<br/>rag_explain_score"]:::mono
end
Users --> Criteria --> Tools
end
subgraph Subregistry["Subregistry (read-only)"]
direction TB
subgraph Ingest["Ingest"]
direction LR
Sources["Upstream MCP registries<br/>(official + optional)"]:::mono
Sync["Sync + normalize<br/>(stable schema)"]:::mono
Catalog["Enriched catalog<br/>(servers + versions)"]:::mono
Sources --> Sync --> Catalog
end
subgraph Enrich["Enrich (adds value)"]
direction LR
Cap["Structured metadata<br/>domain: docs|code|web|mixed<br/>retrieval: dense|sparse|hybrid (+rerank)<br/>freshness: static|continuous (max lag)<br/>grounding: citations|provenance<br/>privacy/auth: local|remote + req|optional<br/>limits: top_k|rate|max ctx"]:::mono
Trust["Trust signals (lightweight)<br/>status, reachability,<br/>schema stability, reports"]:::mono
end
Catalog --> Cap
Catalog --> Trust
end
end
subgraph Selection["Selection (the added value)"]
direction LR
Router["Router<br/>match + rank + explain"]:::mono
Ranked["Ranked candidates<br/>+ reasons + connect info"]:::mono
Retrieval["Chosen retrieval MCP server(s)<br/>(do retrieval)"]:::mono
Router --> Ranked --> Retrieval
end
Tools --> Router
Catalog --> Router
%% Keep the layout without adding a third visible "box" around Inputs.
style Inputs fill:#ffffff,stroke:#ffffff,stroke-width:0px
