diff --git a/editor/CMakeLists.txt b/editor/CMakeLists.txt
index c406869..f42f607 100644
--- a/editor/CMakeLists.txt
+++ b/editor/CMakeLists.txt
@@ -2596,4 +2596,13 @@ target_link_libraries(step412_test PRIVATE
     tree_sitter_javascript tree_sitter_typescript
     tree_sitter_java tree_sitter_rust tree_sitter_go)
 
+add_executable(step413_test tests/step413_test.cpp)
+target_include_directories(step413_test PRIVATE src)
+target_link_libraries(step413_test PRIVATE
+    nlohmann_json::nlohmann_json
+    unofficial::tree-sitter::tree-sitter
+    tree_sitter_python tree_sitter_cpp tree_sitter_elisp
+    tree_sitter_javascript tree_sitter_typescript
+    tree_sitter_java tree_sitter_rust tree_sitter_go)
+
 # Step 12: Dear ImGui shell scaffolding created (main.cpp exists but not built due to dependencies)
diff --git a/editor/src/Pipeline.h b/editor/src/Pipeline.h
index 7b91758..81c6518 100644
--- a/editor/src/Pipeline.h
+++ b/editor/src/Pipeline.h
@@ -130,6 +130,10 @@ public:
             auto pr = PostgreSQLParser::parsePostgreSQLWithDiagnostics(source);
             diags = std::move(pr.diagnostics);
             return std::move(pr.module);
+        } else if (language == "tsql" || language == "sqlserver" || language == "mssql") {
+            auto pr = TSQLParser::parseTSQLWithDiagnostics(source);
+            diags = std::move(pr.diagnostics);
+            return std::move(pr.module);
         } else if (language == "c") {
             auto pr = CParser::parseCWithDiagnostics(source);
             diags = std::move(pr.diagnostics);
@@ -193,6 +197,9 @@ public:
         } else if (language == "postgresql" || language == "postgres") {
             PostgreSQLGenerator gen;
             return gen.generate(ast);
+        } else if (language == "tsql" || language == "sqlserver" || language == "mssql") {
+            TSQLGenerator gen;
+            return gen.generate(ast);
         } else if (language == "c") {
             CGenerator gen;
             return gen.generate(ast);
diff --git a/editor/src/ast/Generator.h b/editor/src/ast/Generator.h
index df4f590..e3f13cb 100644
--- a/editor/src/ast/Generator.h
+++ b/editor/src/ast/Generator.h
@@ -14,6 +14,7 @@
 #include "FSharpGenerator.h"
 #include "VBNetGenerator.h"
 #include "PostgreSQLGenerator.h"
+#include "TSQLGenerator.h"
 #include "CGenerator.h"
 #include "WatGenerator.h"
 #include "CommonLispGenerator.h"
diff --git a/editor/src/ast/Parser.h b/editor/src/ast/Parser.h
index 0cbcec8..2e387f5 100644
--- a/editor/src/ast/Parser.h
+++ b/editor/src/ast/Parser.h
@@ -167,6 +167,7 @@ private:
 #include "ast/FSharpParser.h"
 #include "ast/VBNetParser.h"
 #include "ast/PostgreSQLParser.h"
+#include "ast/TSQLParser.h"
 #include "ast/CParser.h"
 #include "ast/WatParser.h"
 #include "ast/CommonLispParser.h"
diff --git a/editor/src/ast/TSQLGenerator.h b/editor/src/ast/TSQLGenerator.h
new file mode 100644
index 0000000..d229e0f
--- /dev/null
+++ b/editor/src/ast/TSQLGenerator.h
@@ -0,0 +1,161 @@
+#pragma once
+
+#include "PostgreSQLGenerator.h"
+#include "SqlNodes.h"
+
+#include <sstream>
+#include <string>
+
+class TSQLGenerator : public PostgreSQLGenerator {
+public:
+    std::string commentPrefix() const { return "-- "; }
+
+    std::string generate(const ASTNode* node) override {
+        return dispatchGenerate(this, node, "-- Unknown concept: ");
+    }
+
+    std::string visitModule(const Module* module) override {
+        std::ostringstream oss;
+        oss << "-- Module: " << module->name << "\n\n";
+        for (const auto* v : module->getChildren("variables")) {
+            oss << generate(v) << "\n";
+        }
+        for (const auto* stmt : module->getChildren("statements")) {
+            oss << generate(stmt) << "\n";
+        }
+        for (const auto* fn : module->getChildren("functions")) {
+            oss << generate(fn) << "\n";
+        }
+        std::string out = oss.str();
+        while (!out.empty() && (out.back() == '\n' || out.back() == '\r')) out.pop_back();
+        return out;
+    }
+
+    std::string visitFunction(const Function* function) override {
+        std::ostringstream oss;
+        for (const auto* anno : function->getChildren("annotations")) {
+            oss << generate(anno) << "\n";
+        }
+        oss << "CREATE PROCEDURE " << function->name << "\nAS\nBEGIN\n";
+        for (const auto* stmt : function->getChildren("body")) {
+            oss << "    " << generate(stmt) << "\n";
+        }
+        oss << "END;";
+        return oss.str();
+    }
+
+    std::string visitVariable(const Variable* variable) override {
+        std::ostringstream oss;
+        oss << "DECLARE " << variable->name;
+        auto* type = variable->getChild("type");
+        if (type) oss << " " << generate(type);
+        auto* init = variable->getChild("initializer");
+        if (init) oss << " = " << generate(init);
+        oss << ";";
+        return oss.str();
+    }
+
+    std::string visitAssignment(const Assignment* assignment) override {
+        auto* t = assignment->getChild("target");
+        auto* v = assignment->getChild("value");
+        return "SET " + std::string(t ? generate(t) : "@value") +
+               " = " + std::string(v ? generate(v) : "NULL") + ";";
+    }
+
+    std::string visitExpressionStatement(const ExpressionStatement* stmt) override {
+        auto* expr = stmt->getChild("expression");
+        return expr ? generate(expr) : "";
+    }
+
+    std::string visitFunctionCall(const FunctionCall* call) override {
+        std::ostringstream oss;
+        if (call->functionName == "PRINT") {
+            oss << "PRINT ";
+            auto args = call->getChildren("arguments");
+            if (!args.empty()) oss << generate(args.front());
+            oss << ";";
+            return oss.str();
+        }
+
+        oss << call->functionName << "(";
+        auto args = call->getChildren("arguments");
+        for (size_t i = 0; i < args.size(); ++i) {
+            if (i > 0) oss << ", ";
+            oss << generate(args[i]);
+        }
+        oss << ")";
+        return oss.str();
+    }
+
+    std::string visitPrimitiveType(const PrimitiveType* type) override {
+        if (type->kind == "int" || type->kind == "INTEGER") return "INT";
+        if (type->kind == "float" || type->kind == "double") return "FLOAT";
+        if (type->kind == "string" || type->kind == "TEXT") return "NVARCHAR(MAX)";
+        if (type->kind == "bool") return "BIT";
+        if (type->kind == "void") return "VOID";
+        return type->kind;
+    }
+
+    std::string visitTableDeclaration(const ASTNode* node) override {
+        auto* table = static_cast<const TableDeclaration*>(node);
+        std::ostringstream oss;
+        oss << "CREATE TABLE " << table->name << " (";
+
+        auto cols = table->getChildren("columns");
+        if (cols.empty()) {
+            oss << "\n    id INT IDENTITY(1,1) PRIMARY KEY";
+        } else {
+            for (size_t i = 0; i < cols.size(); ++i) {
+                oss << "\n    " << generate(cols[i]);
+                if (i + 1 < cols.size()) oss << ",";
+            }
+        }
+        oss << "\n);";
+        return oss.str();
+    }
+
+    std::string visitSelectQuery(const ASTNode* node) override {
+        auto* q = static_cast<const SelectQuery*>(node);
+        std::ostringstream oss;
+        oss << "SELECT ";
+        auto* topNode = q->getChild("top");
+        if (topNode) {
+            auto* top = static_cast<const IntegerLiteral*>(topNode);
+            oss << "TOP " << top->value << " ";
+        }
+        if (q->distinct) oss << "DISTINCT ";
+
+        auto cols = q->getChildren("columns");
+        if (cols.empty()) {
+            oss << "*";
+        } else {
+            for (size_t i = 0; i < cols.size(); ++i) {
+                if (i > 0) oss << ", ";
+                oss << generate(cols[i]);
+            }
+        }
+
+        auto* from = q->getChild("from");
+        if (from && from->conceptType == "TableDeclaration") {
+            oss << " FROM " << static_cast<const TableDeclaration*>(from)->name;
+        } else if (from) {
+            oss << " FROM " << generate(from);
+        }
+        for (const auto* join : q->getChildren("joins")) {
+            oss << " " << generate(join);
+        }
+        auto* where = q->getChild("where");
+        if (where) oss << " " << generate(where);
+        oss << ";";
+        return oss.str();
+    }
+
+    std::string visitColumnDefinition(const ASTNode* node) override {
+        auto* col = static_cast<const ColumnDefinition*>(node);
+        std::ostringstream oss;
+        oss << col->name << " " << (col->dataType.empty() ? "NVARCHAR(MAX)" : col->dataType);
+        if (!col->nullable) oss << " NOT NULL";
+        if (!col->defaultValue.empty()) oss << " DEFAULT " << col->defaultValue;
+        return oss.str();
+    }
+};
diff --git a/editor/src/ast/TSQLParser.h b/editor/src/ast/TSQLParser.h
new file mode 100644
index 0000000..dbcc52c
--- /dev/null
+++ b/editor/src/ast/TSQLParser.h
@@ -0,0 +1,377 @@
+#pragma once
+
+#include "ASTNode.h"
+#include "Module.h"
+#include "Function.h"
+#include "Variable.h"
+#include "Statement.h"
+#include "Expression.h"
+#include "Type.h"
+#include "SqlNodes.h"
+#include "../ast/Parser.h"
+
+#include <algorithm>
+#include <sstream>
+#include <string>
+#include <vector>
+
+class TSQLParser {
+public:
+    static std::unique_ptr<Module> parseTSQL(const std::string& source) {
+        auto module = std::make_unique<Module>();
+        module->id = IdGenerator::next("mod");
+        module->name = "parsed_tsql_module";
+        module->targetLanguage = "tsql";
+        parseStatements(source, module.get());
+        return module;
+    }
+
+    static ParseResult parseTSQLWithDiagnostics(const std::string& source) {
+        ParseResult result;
+        result.module = parseTSQL(source);
+        return result;
+    }
+
+private:
+    static void parseStatements(const std::string& source, Module* module) {
+        for (const auto& stmtRaw : splitStatements(source)) {
+            std::string stmt = trim(stmtRaw);
+            if (stmt.empty()) continue;
+            std::string lower = toLower(stmt);
+
+            if (startsWith(lower, "create table ")) {
+                parseCreateTable(stmt, module);
+                continue;
+            }
+            if (startsWith(lower, "create index ") || startsWith(lower, "create unique index ")) {
+                parseCreateIndex(stmt, module);
+                continue;
+            }
+            if (startsWith(lower, "select ")) {
+                parseSelect(stmt, module);
+                continue;
+            }
+            if (startsWith(lower, "insert into ")) {
+                parseInsert(stmt, module);
+                continue;
+            }
+            if (startsWith(lower, "update ")) {
+                parseUpdate(stmt, module);
+                continue;
+            }
+            if (startsWith(lower, "delete from ")) {
+                parseDelete(stmt, module);
+                continue;
+            }
+            if (startsWith(lower, "create procedure ")) {
+                parseProcedure(stmt, module);
+                continue;
+            }
+            if (startsWith(lower, "declare ")) {
+                parseDeclare(stmt, module);
+                continue;
+            }
+            if (startsWith(lower, "set ")) {
+                parseSet(stmt, module);
+                continue;
+            }
+            if (startsWith(lower, "print ")) {
+                parsePrint(stmt, module);
+                continue;
+            }
+        }
+    }
+
+    static void parseCreateTable(const std::string& stmt, Module* module) {
+        std::string tableName = extractAfterKeyword(stmt, "TABLE ");
+        tableName = trim(untilDelimiter(tableName, "("));
+
+        auto* table = new TableDeclaration();
+        table->id = IdGenerator::next("table");
+        table->name = tableName;
+        auto dotPos = tableName.find('.');
+        if (dotPos != std::string::npos) table->schema = tableName.substr(0, dotPos);
+
+        auto lp = stmt.find('(');
+        auto rp = stmt.rfind(')');
+        if (lp != std::string::npos && rp != std::string::npos && rp > lp) {
+            std::string cols = stmt.substr(lp + 1, rp - lp - 1);
+            std::stringstream ss(cols);
+            std::string item;
+            while (std::getline(ss, item, ',')) {
+                std::string colLine = trim(item);
+                if (colLine.empty()) continue;
+                std::string lowerCol = toLower(colLine);
+                if (startsWith(lowerCol, "constraint ") ||
+                    startsWith(lowerCol, "primary key") ||
+                    startsWith(lowerCol, "foreign key")) continue;
+
+                std::vector<std::string> parts = splitWhitespace(colLine);
+                if (parts.size() < 2) continue;
+                auto* col = new ColumnDefinition();
+                col->id = IdGenerator::next("col");
+                col->name = parts[0];
+                col->dataType = parts[1];
+                if (parts.size() >= 3 &&
+                    (toLower(parts[2]).find("identity") != std::string::npos ||
+                     toLower(parts[2]).find("(") != std::string::npos)) {
+                    col->dataType += " " + parts[2];
+                }
+                col->nullable = (lowerCol.find("not null") == std::string::npos);
+                table->addChild("columns", col);
+            }
+        }
+
+        module->addChild("statements", table);
+    }
+
+    static void parseCreateIndex(const std::string& stmt, Module* module) {
+        std::string lower = toLower(stmt);
+        bool unique = startsWith(lower, "create unique index ");
+
+        std::string idxName = extractAfterKeyword(stmt, "INDEX ");
+        std::string tableName = extractAfterKeyword(stmt, "ON ");
+        auto* idx = new IndexDefinition();
+        idx->id = IdGenerator::next("idx");
+        idx->name = trim(untilDelimiter(idxName, " ON"));
+        idx->tableName = trim(untilDelimiter(tableName, "("));
+        idx->unique = unique;
+        module->addChild("statements", idx);
+    }
+
+    static void parseSelect(const std::string& stmt, Module* module) {
+        std::string lower = toLower(stmt);
+        auto* q = new SelectQuery();
+        q->id = IdGenerator::next("sel");
+        q->distinct = (lower.find("select distinct") == 0);
+
+        auto topPos = lower.find("select top ");
+        if (topPos == 0) {
+            std::string afterTop = trim(stmt.substr(11));
+            std::string topCount = firstToken(afterTop);
+            if (!topCount.empty() && std::all_of(topCount.begin(), topCount.end(), ::isdigit)) {
+                q->setChild("top", new IntegerLiteral(IdGenerator::next("lit"), std::stoi(topCount)));
+            }
+        }
+
+        auto fromPos = lower.find(" from ");
+        if (fromPos != std::string::npos) {
+            std::string afterFrom = trim(stmt.substr(fromPos + 6));
+            std::string fromName = firstToken(afterFrom);
+            auto* from = new TableDeclaration();
+            from->id = IdGenerator::next("tbl");
+            from->name = fromName;
+            q->setChild("from", from);
+        }
+
+        size_t search = 0;
+        while (true) {
+            auto joinPos = lower.find(" join ", search);
+            if (joinPos == std::string::npos) break;
+            auto tableStart = joinPos + 6;
+            std::string joinRest = stmt.substr(tableStart);
+            std::string tableName = firstToken(joinRest);
+            auto* j = new JoinClause();
+            j->id = IdGenerator::next("join");
+            j->joinType = detectJoinType(lower, joinPos);
+            j->tableName = tableName;
+            q->addChild("joins", j);
+            search = tableStart + 1;
+        }
+
+        auto wherePos = lower.find(" where ");
+        if (wherePos != std::string::npos) {
+            auto* w = new WhereClause();
+            w->id = IdGenerator::next("where");
+            w->expression = trim(stmt.substr(wherePos + 7));
+            q->setChild("where", w);
+        }
+
+        module->addChild("statements", q);
+    }
+
+    static void parseInsert(const std::string& stmt, Module* module) {
+        auto* ins = new InsertStatement();
+        ins->id = IdGenerator::next("ins");
+        ins->tableName = extractAfterKeyword(stmt, "INTO ");
+        ins->tableName = trim(untilDelimiter(ins->tableName, "("));
+        module->addChild("statements", ins);
+    }
+
+    static void parseUpdate(const std::string& stmt, Module* module) {
+        auto* up = new UpdateStatement();
+        up->id = IdGenerator::next("upd");
+        up->tableName = trim(untilDelimiter(extractAfterKeyword(stmt, "UPDATE "), " SET"));
+
+        std::string lower = toLower(stmt);
+        auto wherePos = lower.find(" where ");
+        if (wherePos != std::string::npos) {
+            auto* w = new WhereClause();
+            w->id = IdGenerator::next("where");
+            w->expression = trim(stmt.substr(wherePos + 7));
+            up->setChild("where", w);
+        }
+        module->addChild("statements", up);
+    }
+
+    static void parseDelete(const std::string& stmt, Module* module) {
+        auto* del = new DeleteStatement();
+        del->id = IdGenerator::next("del");
+        del->tableName = trim(untilDelimiter(extractAfterKeyword(stmt, "FROM "), " WHERE"));
+        std::string lower = toLower(stmt);
+        auto wherePos = lower.find(" where ");
+        if (wherePos != std::string::npos) {
+            auto* w = new WhereClause();
+            w->id = IdGenerator::next("where");
+            w->expression = trim(stmt.substr(wherePos + 7));
+            del->setChild("where", w);
+        }
+        module->addChild("statements", del);
+    }
+
+    static void parseProcedure(const std::string& stmt, Module* module) {
+        std::string raw = extractAfterKeyword(stmt, "PROCEDURE ");
+        auto* fn = new Function();
+        fn->id = IdGenerator::next("proc");
+        fn->name = trim(untilDelimiter(raw, " AS"));
+        module->addChild("functions", fn);
+    }
+
+    static void parseDeclare(const std::string& stmt, Module* module) {
+        std::string raw = extractAfterKeyword(stmt, "DECLARE ");
+        std::vector<std::string> parts = splitWhitespace(raw);
+        if (parts.size() < 2) return;
+
+        auto* v = new Variable();
+        v->id = IdGenerator::next("var");
+        v->name = parts[0];
+        v->setChild("type", new PrimitiveType(IdGenerator::next("type"), toUpper(parts[1])));
+
+        auto eqPos = raw.find('=');
+        if (eqPos != std::string::npos) {
+            std::string rhs = trim(raw.substr(eqPos + 1));
+            v->setChild("initializer", parseLiteral(rhs));
+        }
+        module->addChild("variables", v);
+    }
+
+    static void parseSet(const std::string& stmt, Module* module) {
+        std::string raw = extractAfterKeyword(stmt, "SET ");
+        auto eqPos = raw.find('=');
+        if (eqPos == std::string::npos) return;
+
+        auto* assign = new Assignment();
+        assign->id = IdGenerator::next("set");
+        std::string lhs = trim(raw.substr(0, eqPos));
+        std::string rhs = trim(raw.substr(eqPos + 1));
+        assign->setChild("target", new VariableReference(IdGenerator::next("ref"), lhs));
+        assign->setChild("value", parseLiteral(rhs));
+        module->addChild("statements", assign);
+    }
+
+    static void parsePrint(const std::string& stmt, Module* module) {
+        std::string raw = extractAfterKeyword(stmt, "PRINT ");
+        auto* call = new FunctionCall();
+        call->id = IdGenerator::next("call");
+        call->functionName = "PRINT";
+        call->addChild("arguments", parseLiteral(raw));
+
+        auto* es = new ExpressionStatement();
+        es->id = IdGenerator::next("expr");
+        es->setChild("expression", call);
+        module->addChild("statements", es);
+    }
+
+    static ASTNode* parseLiteral(const std::string& tokenRaw) {
+        std::string t = trim(tokenRaw);
+        if (t.empty()) return new NullLiteral();
+        if ((t.front() == '\'' && t.back() == '\'') || (t.front() == '"' && t.back() == '"')) {
+            return new StringLiteral(IdGenerator::next("str"), t.substr(1, t.size() - 2));
+        }
+        if (t == "1" || t == "0") return new IntegerLiteral(IdGenerator::next("int"), std::stoi(t));
+        if (std::all_of(t.begin(), t.end(), [](unsigned char c) { return std::isdigit(c); })) {
+            return new IntegerLiteral(IdGenerator::next("int"), std::stoi(t));
+        }
+        return new VariableReference(IdGenerator::next("ref"), t);
+    }
+
+    static std::string detectJoinType(const std::string& lower, size_t joinPos) {
+        std::string prefix = lower.substr((joinPos > 8 ? joinPos - 8 : 0), 8);
+        if (prefix.find("left") != std::string::npos) return "LEFT";
+        if (prefix.find("right") != std::string::npos) return "RIGHT";
+        if (prefix.find("full") != std::string::npos) return "FULL";
+        return "INNER";
+    }
+
+    static std::vector<std::string> splitStatements(const std::string& source) {
+        std::vector<std::string> out;
+        std::string cur;
+        for (char c : source) {
+            if (c == ';') {
+                if (!trim(cur).empty()) out.push_back(cur);
+                cur.clear();
+                continue;
+            }
+            cur.push_back(c);
+        }
+        if (!trim(cur).empty()) out.push_back(cur);
+        return out;
+    }
+
+    static std::string extractAfterKeyword(const std::string& s, const std::string& keywordUpper) {
+        std::string lower = toLower(s);
+        std::string kw = toLower(keywordUpper);
+        auto pos = lower.find(kw);
+        if (pos == std::string::npos) return "";
+        pos += kw.size();
+        return trim(s.substr(pos));
+    }
+
+    static std::string firstToken(const std::string& s) {
+        std::string t = trim(s);
+        auto end = t.find_first_of(" \t\r\n");
+        if (end == std::string::npos) return t;
+        return t.substr(0, end);
+    }
+
+    static std::string untilDelimiter(const std::string& s, const std::string& delimiterUpper) {
+        std::string lower = toLower(s);
+        std::string d = toLower(delimiterUpper);
+        auto pos = lower.find(d);
+        if (pos == std::string::npos) return s;
+        return s.substr(0, pos);
+    }
+
+    static std::vector<std::string> splitWhitespace(const std::string& s) {
+        std::vector<std::string> out;
+        std::stringstream ss(s);
+        std::string tok;
+        while (ss >> tok) out.push_back(tok);
+        return out;
+    }
+
+    static bool startsWith(const std::string& s, const std::string& prefix) {
+        return s.rfind(prefix, 0) == 0;
+    }
+
+    static std::string toLower(const std::string& s) {
+        std::string out = s;
+        std::transform(out.begin(), out.end(), out.begin(),
+                       [](unsigned char c) { return static_cast<char>(std::tolower(c)); });
+        return out;
+    }
+
+    static std::string toUpper(const std::string& s) {
+        std::string out = s;
+        std::transform(out.begin(), out.end(), out.begin(),
+                       [](unsigned char c) { return static_cast<char>(std::toupper(c)); });
+        return out;
+    }
+
+    static std::string trim(const std::string& s) {
+        auto start = s.find_first_not_of(" \t\r\n");
+        if (start == std::string::npos) return "";
+        auto end = s.find_last_not_of(" \t\r\n");
+        return s.substr(start, end - start + 1);
+    }
+};
diff --git a/editor/tests/step413_test.cpp b/editor/tests/step413_test.cpp
new file mode 100644
index 0000000..4371c3f
--- /dev/null
+++ b/editor/tests/step413_test.cpp
@@ -0,0 +1,213 @@
+// Step 413: T-SQL Parser + Generator Tests (12 tests)
+
+#include "ast/TSQLParser.h"
+#include "ast/TSQLGenerator.h"
+#include "ast/SqlNodes.h"
+#include "ast/Function.h"
+#include "ast/Variable.h"
+#include "Pipeline.h"
+
+#include <iostream>
+#include <string>
+#include <vector>
+
+static int passed = 0, failed = 0;
+#define TEST(name) { std::cout << "  " << #name << "... "; }
+#define PASS() { std::cout << "PASS\n"; ++passed; }
+#define FAIL(msg) { std::cout << "FAIL: " << msg << "\n"; ++failed; }
+#define CHECK(cond, msg) if (!(cond)) { FAIL(msg); return; } else {}
+
+template <typename T>
+T* firstStatementOf(const Module* mod, const std::string& conceptName) {
+    for (auto* s : mod->getChildren("statements")) {
+        if (s->conceptType == conceptName) return static_cast<T*>(s);
+    }
+    return nullptr;
+}
+
+void test_parse_create_table_identity_nvarchar() {
+    TEST(parse_create_table_identity_nvarchar);
+    auto mod = TSQLParser::parseTSQL(
+        "CREATE TABLE users (id INT IDENTITY(1,1), name NVARCHAR(100) NOT NULL);\n");
+    CHECK(mod != nullptr, "module null");
+    auto* t = firstStatementOf<TableDeclaration>(mod.get(), "TableDeclaration");
+    CHECK(t != nullptr, "expected table declaration");
+    CHECK(t->name == "users", "expected users table");
+    auto cols = t->getChildren("columns");
+    CHECK(cols.size() == 2, "expected two columns");
+    CHECK(static_cast<ColumnDefinition*>(cols[0])->dataType.find("IDENTITY") != std::string::npos,
+          "expected identity type");
+    CHECK(static_cast<ColumnDefinition*>(cols[1])->dataType.find("NVARCHAR") != std::string::npos,
+          "expected nvarchar type");
+    PASS();
+}
+
+void test_parse_select_top_where() {
+    TEST(parse_select_top_where);
+    auto mod = TSQLParser::parseTSQL("SELECT TOP 5 id FROM users WHERE active = 1;\n");
+    auto* q = firstStatementOf<SelectQuery>(mod.get(), "SelectQuery");
+    CHECK(q != nullptr, "expected select query");
+    CHECK(q->getChild("top") != nullptr, "expected top child");
+    CHECK(q->getChild("where") != nullptr, "expected where child");
+    PASS();
+}
+
+void test_parse_create_procedure_marker() {
+    TEST(parse_create_procedure_marker);
+    auto mod = TSQLParser::parseTSQL(
+        "CREATE PROCEDURE usp_cleanup AS BEGIN DELETE FROM logs; END;\n");
+    auto fns = mod->getChildren("functions");
+    CHECK(fns.size() == 1, "expected one procedure marker");
+    auto* fn = static_cast<Function*>(fns.front());
+    CHECK(fn->name == "usp_cleanup", "expected procedure name");
+    PASS();
+}
+
+void test_parse_declare_variable() {
+    TEST(parse_declare_variable);
+    auto mod = TSQLParser::parseTSQL("DECLARE @count INT = 10;\n");
+    auto vars = mod->getChildren("variables");
+    CHECK(vars.size() == 1, "expected one variable");
+    auto* v = static_cast<Variable*>(vars.front());
+    CHECK(v->name == "@count", "expected variable name");
+    CHECK(v->getChild("initializer") != nullptr, "expected initializer");
+    PASS();
+}
+
+void test_parse_set_assignment() {
+    TEST(parse_set_assignment);
+    auto mod = TSQLParser::parseTSQL("SET @count = 11;\n");
+    auto* a = firstStatementOf<Assignment>(mod.get(), "Assignment");
+    CHECK(a != nullptr, "expected assignment statement");
+    auto* target = static_cast<VariableReference*>(a->getChild("target"));
+    CHECK(target != nullptr && target->variableName == "@count", "expected assignment target");
+    PASS();
+}
+
+void test_parse_print_statement() {
+    TEST(parse_print_statement);
+    auto mod = TSQLParser::parseTSQL("PRINT 'done';\n");
+    auto* es = firstStatementOf<ExpressionStatement>(mod.get(), "ExpressionStatement");
+    CHECK(es != nullptr, "expected expression statement");
+    auto* call = static_cast<FunctionCall*>(es->getChild("expression"));
+    CHECK(call != nullptr && call->functionName == "PRINT", "expected print call");
+    PASS();
+}
+
+void test_generate_select_top_clause() {
+    TEST(generate_select_top_clause);
+    SelectQuery q;
+    q.id = "q1";
+    q.setChild("top", new IntegerLiteral("i1", 3));
+    q.setChild("from", new TableDeclaration("t1", "users"));
+    TSQLGenerator gen;
+    std::string out = gen.generate(&q);
+    CHECK(out.find("SELECT TOP 3") != std::string::npos, "expected top syntax");
+    CHECK(out.find("FROM users") != std::string::npos, "expected from clause");
+    PASS();
+}
+
+void test_generate_create_table_identity() {
+    TEST(generate_create_table_identity);
+    TableDeclaration t("t1", "users");
+    t.addChild("columns", new ColumnDefinition("c1", "id", "INT IDENTITY(1,1)", false));
+    t.addChild("columns", new ColumnDefinition("c2", "name", "NVARCHAR(100)", false));
+    TSQLGenerator gen;
+    std::string out = gen.generate(&t);
+    CHECK(out.find("CREATE TABLE users") != std::string::npos, "expected create table");
+    CHECK(out.find("INT IDENTITY(1,1)") != std::string::npos, "expected identity");
+    CHECK(out.find("NVARCHAR(100)") != std::string::npos, "expected nvarchar");
+    PASS();
+}
+
+void test_generate_procedure_begin_end() {
+    TEST(generate_procedure_begin_end);
+    Function fn("f1", "usp_sync");
+    fn.addChild("body", new Return());
+    TSQLGenerator gen;
+    std::string out = gen.generate(&fn);
+    CHECK(out.find("CREATE PROCEDURE usp_sync") != std::string::npos, "expected procedure keyword");
+    CHECK(out.find("BEGIN") != std::string::npos, "expected begin block");
+    CHECK(out.find("END;") != std::string::npos, "expected end block");
+    PASS();
+}
+
+void test_generate_declare_set_print() {
+    TEST(generate_declare_set_print);
+    Variable v("v1", "@n");
+    v.setChild("type", new PrimitiveType("t1", "int"));
+    v.setChild("initializer", new IntegerLiteral("i1", 1));
+
+    Assignment a;
+    a.id = "a1";
+    a.setChild("target", new VariableReference("r1", "@n"));
+    a.setChild("value", new IntegerLiteral("i2", 2));
+
+    FunctionCall printCall;
+    printCall.id = "p1";
+    printCall.functionName = "PRINT";
+    printCall.addChild("arguments", new StringLiteral("s1", "ok"));
+
+    TSQLGenerator gen;
+    std::string d = gen.generate(&v);
+    std::string s = gen.generate(&a);
+    std::string p = gen.generate(&printCall);
+    CHECK(d.find("DECLARE @n INT = 1;") != std::string::npos, "expected declare");
+    CHECK(s.find("SET @n = 2;") != std::string::npos, "expected set");
+    CHECK(p == "PRINT 'ok';", "expected print syntax");
+    PASS();
+}
+
+void test_pipeline_parse_and_generate_aliases() {
+    TEST(pipeline_parse_and_generate_aliases);
+    Pipeline p;
+    std::vector<ParseDiagnostic> d1, d2, d3;
+    auto m1 = p.parse("SELECT TOP 1 id FROM users;\n", "tsql", d1);
+    auto m2 = p.parse("SELECT TOP 1 id FROM users;\n", "sqlserver", d2);
+    auto m3 = p.parse("SELECT TOP 1 id FROM users;\n", "mssql", d3);
+    CHECK(m1 && m2 && m3, "expected parse via aliases");
+    CHECK(m1->targetLanguage == "tsql", "expected tsql target");
+
+    DeleteStatement del("d1", "audit");
+    std::string o1 = p.generate(&del, "tsql");
+    std::string o2 = p.generate(&del, "sqlserver");
+    std::string o3 = p.generate(&del, "mssql");
+    CHECK(o1.find("DELETE FROM audit;") != std::string::npos, "tsql route");
+    CHECK(o2.find("DELETE FROM audit;") != std::string::npos, "sqlserver route");
+    CHECK(o3.find("DELETE FROM audit;") != std::string::npos, "mssql route");
+    PASS();
+}
+
+void test_parser_to_generator_tsql_flow() {
+    TEST(parser_to_generator_tsql_flow);
+    auto mod = TSQLParser::parseTSQL(
+        "DECLARE @limit INT = 10;\n"
+        "SELECT TOP 10 id FROM users WHERE active = 1;\n");
+    CHECK(mod != nullptr, "module null");
+    TSQLGenerator gen;
+    std::string out = gen.generate(mod.get());
+    CHECK(out.find("DECLARE @limit INT = 10;") != std::string::npos, "expected declare output");
+    CHECK(out.find("SELECT TOP 10") != std::string::npos, "expected top output");
+    PASS();
+}
+
+int main() {
+    std::cout << "Step 413: T-SQL Parser + Generator Tests\n";
+
+    test_parse_create_table_identity_nvarchar(); // 1
+    test_parse_select_top_where();               // 2
+    test_parse_create_procedure_marker();        // 3
+    test_parse_declare_variable();               // 4
+    test_parse_set_assignment();                 // 5
+    test_parse_print_statement();                // 6
+    test_generate_select_top_clause();           // 7
+    test_generate_create_table_identity();       // 8
+    test_generate_procedure_begin_end();         // 9
+    test_generate_declare_set_print();           // 10
+    test_pipeline_parse_and_generate_aliases();  // 11
+    test_parser_to_generator_tsql_flow();        // 12
+
+    std::cout << "\nResults: " << passed << "/" << (passed + failed)
+              << " passed\n";
+    return failed == 0 ? 0 : 1;
+}
diff --git a/progress.md b/progress.md
index 778f354..d784f93 100644
--- a/progress.md
+++ b/progress.md
@@ -4019,6 +4019,61 @@ the SQL AST nodes introduced in Step 410 and parsed in Step 411.
   - `editor/src/MCPServer.h` (`1679` > `600`)
   - `editor/src/HeadlessAgentRPCHandler.h` (`2629` > `600`)
 
+### Step 413: T-SQL Parser + Generator
+**Status:** PASS (12/12 tests)
+
+Added Microsoft SQL Server (T-SQL) dialect support with parser and generator
+coverage for dialect-specific constructs (`TOP`, `IDENTITY`, `NVARCHAR`,
+`DECLARE`/`SET`/`PRINT`, stored procedures).
+
+**Files created:**
+- `editor/src/ast/TSQLParser.h` — T-SQL parse support:
+  - `parseTSQL(...)` and `parseTSQLWithDiagnostics(...)`
+  - `CREATE TABLE`, `CREATE INDEX`, `SELECT`, `INSERT`, `UPDATE`, `DELETE`
+  - `SELECT TOP n` captured via `SelectQuery` child `"top"`
+  - `CREATE PROCEDURE ... AS BEGIN ... END` mapped to `Function` markers
+  - `DECLARE`, `SET`, `PRINT` mapped to `Variable`, `Assignment`,
+    and `ExpressionStatement(FunctionCall)`
+- `editor/src/ast/TSQLGenerator.h` — T-SQL generation support:
+  - `SELECT TOP n` emission
+  - `CREATE PROCEDURE ... AS BEGIN ... END`
+  - `DECLARE` / `SET` / `PRINT` statements
+  - T-SQL-oriented primitive type mapping (`INT`, `FLOAT`, `NVARCHAR(MAX)`, `BIT`)
+- `editor/tests/step413_test.cpp` — 12 tests covering:
+  1. CREATE TABLE with IDENTITY and NVARCHAR parse
+  2. SELECT TOP + WHERE parse
+  3. CREATE PROCEDURE parse marker
+  4. DECLARE parse
+  5. SET parse
+  6. PRINT parse
+  7. SELECT TOP generation
+  8. CREATE TABLE with IDENTITY generation
+  9. PROCEDURE BEGIN/END generation
+  10. DECLARE/SET/PRINT generation
+  11. pipeline parse/generate alias routing (`tsql`, `sqlserver`, `mssql`)
+  12. parser-to-generator T-SQL flow
+
+**Files modified:**
+- `editor/src/ast/Parser.h` — include `ast/TSQLParser.h`
+- `editor/src/ast/Generator.h` — include `TSQLGenerator.h`
+- `editor/src/Pipeline.h` — parse + generate routing for `tsql`, `sqlserver`, `mssql`
+- `editor/CMakeLists.txt` — `step413_test` target
+
+**Verification run:**
+- `step413_test` — PASS (12/12) new step coverage
+- `step412_test` — PASS (12/12) regression coverage
+- `step411_test` — PASS (12/12) regression coverage
+
+**Architecture gate check:**
+- `editor/src/ast/TSQLParser.h` within header-size limit (`377` <= `600`)
+- `editor/src/ast/TSQLGenerator.h` within header-size limit (`161` <= `600`)
+- `editor/tests/step413_test.cpp` within test-file size guidance (`213` lines)
+- `editor/src/Pipeline.h` within header-size limit (`261` <= `600`)
+- Legacy oversized headers persist:
+  - `editor/src/ast/Serialization.h` (`1427` > `600`)
+  - `editor/src/MCPServer.h` (`1679` > `600`)
+  - `editor/src/HeadlessAgentRPCHandler.h` (`2629` > `600`)
+
 # Roadmap Planning — Sprints 12-25+
 
 ## Status: Planning Complete (Sprints 12-19 detailed, 20-25 in roadmap.md)