diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index 181939a5..a4afd97a 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -335,6 +335,18 @@ jobs:
         check-latest: true
         cache: true
       id: go
+
+    - name: Check go sum coherence
+      run: |
+        cp go.sum go.sum.bkp
+        sumDiff="$(diff go.sum go.sum.bkp)" || true;
+        if [ "$sumDiff" = "" ]; then 
+          echo "go.sum check passed"
+        else 
+          echo "go.sum is inconsistent, might be time to run 'go mod tidy' and commit";
+          exit 1;
+        fi
+
     
     - name: Setup Python
       uses: actions/setup-python@v5.0.0
diff --git a/.gitignore b/.gitignore
index 5a47f250..2400fdb4 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,4 +1,7 @@
 
+# CI staging
+go.sum.bkp
+
 # Windows
 *.exe
 
diff --git a/docs/diagrams/plantuml/hld-components.png b/docs/diagrams/plantuml/hld-components.png
index 9f771254..c26a1683 100644
Binary files a/docs/diagrams/plantuml/hld-components.png and b/docs/diagrams/plantuml/hld-components.png differ
diff --git a/docs/diagrams/plantuml/hld-components.puml b/docs/diagrams/plantuml/hld-components.puml
index f561cc37..84965736 100644
--- a/docs/diagrams/plantuml/hld-components.puml
+++ b/docs/diagrams/plantuml/hld-components.puml
@@ -1,20 +1,29 @@
 @startuml
 
-node "Openapi-StackQL" as OpenapiStackQL
-node "StackQL Parser" as StackQLParser
+node "any-sdk" as AnySdk
+node "stackql-parser" as StackQLParser
 node "psql-wire" as PsqlWire
+node "stackql-provider-registry" as ProviderRegistry
+node "stackql-go-sqlite3" as StackqlSqlite
+node "postgres" as Postgres
+node "postgres clients\neg: libpq" as PostgresClient
+node "AI agents\neg: Claude Code" as AIAgent
 
 [Shell] ..> [Command Runner]
 [Exec] ..> [Command Runner]
 [Command Runner] ..> [Driver]
+PostgresClient ->  [Server]
 [Server] ..> [Driver]
 [Server] ..> [Wire Server]
 [Wire Server] ..> PsqlWire
+[MCP Server] ..> [Driver]
+AIAgent -> [MCP Server]
 [Driver] ..> [Query Submitter]
 [Query Submitter] ..> [Plan Builder]
 [Plan Builder] ..> [Initial Passes Screener Analyzer] : Mature the AST
 [Initial Passes Screener Analyzer] ..> [Initial Passes Screener Analyzer] : Nested Indirection
 [Initial Passes Screener Analyzer] ..> [Indirect] : Indirect Expansion
+[Initial Passes Screener Analyzer] ..> ProviderRegistry
 [Plan Builder] ..> [Parser]
 [Indirect] ..> [Parser]
 [Parser] ..> StackQLParser
@@ -22,9 +31,14 @@ node "psql-wire" as PsqlWire
 [Plan Builder] ..> [Primitive Builder]
 [Primitive Builder] ..> [Primitive Graph]
 [Plan Builder] ..> [Primitive Graph]
-[Primitive Builder] ..> OpenapiStackQL
+[Primitive Graph] ..> [Executor]
+[Executor] ..> [Relational Algebra]
+[Executor] ..> ProviderRegistry
+[Relational Algebra] ..> StackqlSqlite
+[Relational Algebra] -> Postgres
+[Primitive Builder] ..> AnySdk
 [Route Pass] ..> [Parameter Router]
-[Parameter Router] ..> OpenapiStackQL
+[Parameter Router] ..> AnySdk
 [Route Pass] ..> [Route Pass] : Nesting / Composition
 
 
diff --git a/pkg/mcp_server/server.go b/pkg/mcp_server/server.go
index f6cff8e3..7c2b48a6 100644
--- a/pkg/mcp_server/server.go
+++ b/pkg/mcp_server/server.go
@@ -166,7 +166,7 @@ func newMCPServer(config *Config, backend Backend, logger *logrus.Logger) (MCPSe
 		server,
 		&mcp.Tool{
 			Name:        "query_v2",
-			Description: "Execute a SQL query.  Please adhere to the expected parameters.  Returns a textual response",
+			Description: "Deprecated: Please switch to query_v3. Execute a SQL query.  Please adhere to the expected parameters.  Returns a textual response",
 			// Input and output schemas can be defined here if needed.
 		},
 		func(ctx context.Context, req *mcp.CallToolRequest, arg dto.QueryInput) (*mcp.CallToolResult, any, error) {
@@ -279,7 +279,7 @@ func newMCPServer(config *Config, backend Backend, logger *logrus.Logger) (MCPSe
 		server,
 		&mcp.Tool{
 			Name:        "prompt_write_safe_select_tool",
-			Description: "Prompt: guidelines for writing safe SELECT queries.",
+			Description: "PLACEHOLDER Future proofing: prompt guidelines for writing safe SELECT queries.",
 		},
 		func(ctx context.Context, req *mcp.CallToolRequest, args dto.HierarchyInput) (*mcp.CallToolResult, any, error) {
 			result, err := backend.PromptWriteSafeSelectTool(ctx, args)
@@ -292,25 +292,6 @@ func newMCPServer(config *Config, backend Backend, logger *logrus.Logger) (MCPSe
 		},
 	)
 
-	// mcp.AddTool(
-	// 	server,
-	// 	&mcp.Tool{
-	// 		Name:        "prompt_explain_plan_tips_tool",
-	// 		Description: "Prompt: tips for reading EXPLAIN ANALYZE output.",
-	// 	},
-	// 	func(ctx context.Context, req *mcp.CallToolRequest, _ any) (*mcp.CallToolResult, any, error) {
-	// 		result, err := backend.PromptExplainPlanTipsTool(ctx)
-	// 		if err != nil {
-	// 			return nil, nil, err
-	// 		}
-	// 		return &mcp.CallToolResult{
-	// 			Content: []mcp.Content{
-	// 				&mcp.TextContent{Text: result},
-	// 			},
-	// 		}, result, nil
-	// 	},
-	// )
-
 	mcp.AddTool(
 		server,
 		&mcp.Tool{
@@ -338,7 +319,7 @@ func newMCPServer(config *Config, backend Backend, logger *logrus.Logger) (MCPSe
 		server,
 		&mcp.Tool{
 			Name:        "list_tables_json_page",
-			Description: "List tables with pagination and filters, returns JSON.",
+			Description: "Future proofing: List tables with pagination and filters, returns JSON.",
 		},
 		func(ctx context.Context, req *mcp.CallToolRequest, args dto.ListTablesPageInput) (*mcp.CallToolResult, any, error) {
 			result, err := backend.ListTablesJSONPage(ctx, args)
@@ -429,7 +410,7 @@ func newMCPServer(config *Config, backend Backend, logger *logrus.Logger) (MCPSe
 		server,
 		&mcp.Tool{
 			Name:        "describe_table",
-			Description: "Get detailed information about a table.",
+			Description: "PLACEHOLDER Future proofing: Get detailed information about a table.",
 		},
 		func(ctx context.Context, req *mcp.CallToolRequest, args dto.HierarchyInput) (*mcp.CallToolResult, any, error) {
 			result, err := backend.DescribeTable(ctx, args)
@@ -446,7 +427,7 @@ func newMCPServer(config *Config, backend Backend, logger *logrus.Logger) (MCPSe
 		server,
 		&mcp.Tool{
 			Name:        "get_foreign_keys",
-			Description: "Get foreign key information for a table.",
+			Description: "PLACEHOLDER Future proofing: Get foreign key information for a table.",
 		},
 		func(ctx context.Context, req *mcp.CallToolRequest, args dto.HierarchyInput) (*mcp.CallToolResult, any, error) {
 			result, err := backend.GetForeignKeys(ctx, args)
@@ -463,7 +444,7 @@ func newMCPServer(config *Config, backend Backend, logger *logrus.Logger) (MCPSe
 		server,
 		&mcp.Tool{
 			Name:        "find_relationships",
-			Description: "Find explicit and implied relationships for a table.",
+			Description: "PLACEHOLDER Future proofing: Find explicit and implied relationships for a table.",
 		},
 		func(ctx context.Context, req *mcp.CallToolRequest, args dto.HierarchyInput) (*mcp.CallToolResult, any, error) {
 			result, err := backend.FindRelationships(ctx, args)
@@ -476,10 +457,6 @@ func newMCPServer(config *Config, backend Backend, logger *logrus.Logger) (MCPSe
 		},
 	)
 
-	// --- new: register namespaced meta.* and query.* tools ---
-	registerNamespacedTools(server, backend, logger)
-	// ---------------------------------------------------------
-
 	return &simpleMCPServer{
 		config:           config,
 		backend:          backend,
@@ -553,137 +530,3 @@ func (s *simpleMCPServer) Stop() error {
 	s.logger.Printf("MCP server stopped")
 	return nil
 }
-
-// registerNamespacedTools adds meta.* and query.* tools (namespaced variants).
-//
-//nolint:gocognit,funlen // ok for now
-func registerNamespacedTools(server *mcp.Server, backend Backend, logger *logrus.Logger) {
-	// meta.server_info
-	mcp.AddTool(
-		server,
-		&mcp.Tool{
-			Name:        "meta.server_info",
-			Description: "Namespaced: Get server information.",
-		},
-		func(ctx context.Context, req *mcp.CallToolRequest, _ any) (*mcp.CallToolResult, dto.ServerInfoDTO, error) {
-			info, err := backend.ServerInfo(ctx, nil)
-			if err != nil {
-				return nil, dto.ServerInfoDTO{}, err
-			}
-			out := dto.ServerInfoDTO{Name: info.Name, Info: info.Info, IsReadOnly: info.IsReadOnly}
-			bytesOut, _ := json.Marshal(out)
-			return &mcp.CallToolResult{Content: []mcp.Content{&mcp.TextContent{Text: string(bytesOut)}}}, out, nil
-		},
-	)
-
-	// meta.db_identity
-	mcp.AddTool(
-		server,
-		&mcp.Tool{
-			Name:        "meta.db_identity",
-			Description: "Namespaced: Get current database identity.",
-		},
-		func(ctx context.Context, req *mcp.CallToolRequest, _ any) (*mcp.CallToolResult, dto.DBIdentityDTO, error) {
-			id, err := backend.DBIdentity(ctx, nil)
-			if err != nil {
-				return nil, dto.DBIdentityDTO{}, err
-			}
-			out := dto.DBIdentityDTO{Identity: fmt.Sprintf("%v", id["identity"])}
-			bytesOut, _ := json.Marshal(out)
-			return &mcp.CallToolResult{Content: []mcp.Content{&mcp.TextContent{Text: string(bytesOut)}}}, out, nil
-		},
-	)
-
-	mcp.AddTool(
-		server,
-		&mcp.Tool{
-			Name:        "query.exec_text",
-			Description: "Namespaced: Execute SQL returning textual result.",
-		},
-		func(ctx context.Context, req *mcp.CallToolRequest, arg dto.QueryInput) (*mcp.CallToolResult, any, error) {
-			logger.Infof("query.exec_text SQL: %s", arg.SQL)
-			rawText, err := backend.RunQuery(ctx, arg)
-			if err != nil {
-				return nil, nil, err
-			}
-			out := dto.QueryResultDTO{Raw: rawText, Format: "text"}
-			bytesOut, _ := json.Marshal(out)
-			return &mcp.CallToolResult{Content: []mcp.Content{&mcp.TextContent{Text: string(bytesOut)}}}, out, nil
-		},
-	)
-
-	mcp.AddTool(
-		server,
-		&mcp.Tool{
-			Name:        "query.exec_json",
-			Description: "Namespaced: Execute SQL returning JSON array as text.",
-		},
-		func(ctx context.Context, req *mcp.CallToolRequest, arg dto.QueryJSONInput) (*mcp.CallToolResult, any, error) {
-			rows, err := backend.RunQueryJSON(ctx, arg)
-			if err != nil {
-				return nil, nil, err
-			}
-			dtObj := dto.QueryResultDTO{
-				Rows:     rows,
-				RowCount: len(rows),
-				Format:   "json",
-			}
-			bytesOut, _ := json.Marshal(dtObj)
-			return &mcp.CallToolResult{Content: []mcp.Content{&mcp.TextContent{Text: string(bytesOut)}}}, dtObj, nil
-		},
-	)
-
-	// meta_describe_table
-	mcp.AddTool(
-		server,
-		&mcp.Tool{
-			Name:        "meta_describe_table",
-			Description: "Describe a stackql relation.  This publishes the bullk of the columns returned from a SELECT.",
-		},
-		func(ctx context.Context, req *mcp.CallToolRequest, args dto.HierarchyInput) (*mcp.CallToolResult, any, error) {
-			result, err := backend.DescribeTable(ctx, args)
-			if err != nil {
-				return nil, nil, err
-			}
-			out := dto.QueryResultDTO{Rows: result, RowCount: len(result), Format: "json"}
-			bytesOut, _ := json.Marshal(out)
-			return &mcp.CallToolResult{Content: []mcp.Content{&mcp.TextContent{Text: string(bytesOut)}}}, out, nil
-		},
-	)
-
-	// meta.get_foreign_keys
-	mcp.AddTool(
-		server,
-		&mcp.Tool{
-			Name:        "meta.get_foreign_keys",
-			Description: "Namespaced: Get foreign keys for a table.",
-		},
-		func(ctx context.Context, req *mcp.CallToolRequest, args dto.HierarchyInput) (*mcp.CallToolResult, any, error) {
-			result, err := backend.GetForeignKeys(ctx, args)
-			if err != nil {
-				return nil, nil, err
-			}
-			out := dto.QueryResultDTO{Rows: result, RowCount: len(result), Format: "json"}
-			bytesOut, _ := json.Marshal(out)
-			return &mcp.CallToolResult{Content: []mcp.Content{&mcp.TextContent{Text: string(bytesOut)}}}, out, nil
-		},
-	)
-
-	// meta.find_relationships
-	mcp.AddTool(
-		server,
-		&mcp.Tool{
-			Name:        "meta.find_relationships",
-			Description: "Namespaced: Find relationships for a table.",
-		},
-		func(ctx context.Context, req *mcp.CallToolRequest, args dto.HierarchyInput) (*mcp.CallToolResult, any, error) {
-			result, err := backend.FindRelationships(ctx, args)
-			if err != nil {
-				return nil, nil, err
-			}
-			out := dto.SimpleTextDTO{Text: result}
-			bytesOut, _ := json.Marshal(out)
-			return &mcp.CallToolResult{Content: []mcp.Content{&mcp.TextContent{Text: string(bytesOut)}}}, out, nil
-		},
-	)
-}
diff --git a/test/robot/functional/mcp.robot b/test/robot/functional/mcp.robot
index eeeeefbf..da2fbfd8 100644
--- a/test/robot/functional/mcp.robot
+++ b/test/robot/functional/mcp.robot
@@ -325,46 +325,6 @@ MCP HTTPS Server JSON DTO Query V3 JSON
     ${row_count}=    Get From Dictionary    ${query_obj}    row_count
     Should Be True    ${row_count} > 0
 
-MCP HTTPS Server Query Exec Text
-    Pass Execution If    "%{IS_SKIP_MCP_TEST=false}" == "true"    Some platforms do not have the MCP client available
-    # Future proofing: raw text format reserved; may gain structured hints later.
-    ${ns_query_text}=    Run Process
-    ...    ${STACKQL_MCP_CLIENT_EXE}
-    ...    exec
-    ...    \-\-client\-type\=http
-    ...    \-\-url\=https://127.0.0.1:9004
-    ...    \-\-client\-cfg
-    ...    { "apply_tls_globally": true, "insecure_skip_verify": true, "ca_file": "test/server/mtls/credentials/pg_server_cert.pem", "promote_leaf_to_ca": true }
-    ...    \-\-exec.action
-    ...    query.exec_text
-    ...    \-\-exec.args
-    ...    {"sql":"SELECT 1 as foo"}
-    ...    stdout=${CURDIR}${/}tmp${/}MCP-HTTPS-query-exec-text.txt
-    ...    stderr=${CURDIR}${/}tmp${/}MCP-HTTPS-query-exec-text-stderr.txt
-    Should Be Equal As Integers    ${ns_query_text.rc}    0
-    Should Contain     ${ns_query_text.stdout}   foo
-
-MCP HTTPS Server JSON DTO Query Exec JSON
-    Pass Execution If    "%{IS_SKIP_MCP_TEST=false}" == "true"    Some platforms do not have the MCP client available
-    ${ns_query_json}=    Run Process
-    ...    ${STACKQL_MCP_CLIENT_EXE}
-    ...    exec
-    ...    \-\-client\-type\=http
-    ...    \-\-url\=https://127.0.0.1:9004
-    ...    \-\-client\-cfg
-    ...    { "apply_tls_globally": true, "insecure_skip_verify": true, "ca_file": "test/server/mtls/credentials/pg_server_cert.pem", "promote_leaf_to_ca": true }
-    ...    \-\-exec.action
-    ...    query.exec_json
-    ...    \-\-exec.args
-    ...    {"sql":"SELECT 1 as foo","row_limit":5}
-    ...    stdout=${CURDIR}${/}tmp${/}MCP-HTTPS-query-exec-json.txt
-    ...    stderr=${CURDIR}${/}tmp${/}MCP-HTTPS-query-exec-json-stderr.txt
-    Should Be Equal As Integers    ${ns_query_json.rc}    0
-    ${ns_query_json_obj}=    Parse MCP JSON Output    ${ns_query_json.stdout}
-    Should Be Equal    ${ns_query_json_obj["format"]}    json
-    ${ns_row_count}=    Get From Dictionary    ${ns_query_json_obj}    row_count
-    Should Be True    ${ns_row_count} >= 0
-
 MCP HTTPS Server JSON DTO Meta Get Foreign Keys
     [Documentation]     Future proofing: foreign key discovery not yet implemented; placeholder.
     Pass Execution If    "%{IS_SKIP_MCP_TEST=false}" == "true"    Some platforms do not have the MCP client available
@@ -376,7 +336,7 @@ MCP HTTPS Server JSON DTO Meta Get Foreign Keys
     ...    \-\-client\-cfg
     ...    { "apply_tls_globally": true, "insecure_skip_verify": true, "ca_file": "test/server/mtls/credentials/pg_server_cert.pem", "promote_leaf_to_ca": true }
     ...    \-\-exec.action
-    ...    meta.get_foreign_keys
+    ...    get_foreign_keys
     ...    \-\-exec.args
     ...    {"provider":"google","service":"cloudresourcemanager","resource":"projects"}
     ...    stdout=${CURDIR}${/}tmp${/}MCP-HTTPS-meta-get-foreign-keys.txt
@@ -395,7 +355,7 @@ MCP HTTPS Server JSON DTO Meta Find Relationships
     ...    \-\-client\-cfg
     ...    { "apply_tls_globally": true, "insecure_skip_verify": true, "ca_file": "test/server/mtls/credentials/pg_server_cert.pem", "promote_leaf_to_ca": true }
     ...    \-\-exec.action
-    ...    meta.find_relationships
+    ...    find_relationships
     ...    \-\-exec.args
     ...    {"provider":"google","service":"cloudresourcemanager","resource":"projects"}
     ...    stdout=${CURDIR}${/}tmp${/}MCP-HTTPS-meta-find-relationships.txt