comptime VM: flip Type to .type_value; migrate the .any refs that mean a Type value

type_resolver "Type" -> .type_value; const_type result + emitConstType now a
bare 8-byte i64 handle (not a 16-byte Any box). Migrated every .any ref meaning
"a Type value", leaving real boxed-Any refs:

- "Any holds a Type" meta-marker tag .any -> .type_value at all 4 consumers
  (reflectArgTypeId, reflectTypeId, the comptime type_tag-as-struct path,
  resolveTypeCategoryTags "type").
- reflection-builtin return types (type_of/declare/define) -> .type_value;
  runtime type_of(any) reads the tag as a .type_value (no re-box).
- expr_typer: a bare type-name expr is .type_value (backtick is_raw exempt).
- reflectionArgIsType accepts .type_value OR .any (a reflection arg can be a
  bare Type or a boxed Any).
- comptime switch_br accepts a .type_tag discriminant (type-category match).
- a bare function name in a Type slot -> const_type(its function type), not a
  func-ref (fixes a JIT crash); old string-box kept only for genuine Any params.
- field-not-found diagnostic + formatTypeName render .type_value as "Type".

Fixed 3 unit tests asserting the old .any behavior. 697/0 both gates (gate ON
bails cleanly to legacy since the VM doesn't model Type values yet) + 494 unit
tests. 24 snapshots regenerated (22 .ir const_type shape; 2 .stderr Any->Type).

current/CHECKPOINT-COMPILER-API.md

@@ -335,6 +335,31 @@ when reached (sentinels or accessor fns; see the design doc Risks).
   `List` growth; orthogonal, see `current/CHECKPOINT-METATYPE.md`.)
 
 ## Log
+- **Phase 3 P3.4 step 3 (VM plan) — dedicated `Type` builtin TypeId: RESOLVER FLIPPED + `.any` migration (2026-06-18).**
+  Flipped `type_resolver:64` (`"Type"` → `.type_value`), `module.zig` `constType` (result type
+  → `.type_value`), and `emitConstType` (a bare i64 carrying `tid.index()`, NOT a 16-byte Any
+  box). Then migrated every `.any` reference that means "a Type value", classified per CLAUDE.md
+  (leave the real boxed-Any refs): (a) the "Any holds a Type" **meta-marker tag** moved `.any` →
+  `.type_value` at all 4 consumers — `reflectArgTypeId` (LLVM), `reflectTypeId` + the
+  `.type_tag`-as-struct-field comptime path (interp), and `resolveTypeCategoryTags("type")`
+  (generic.zig); (b) reflection-builtin RETURN types `.any` → `.type_value` (`type_of`/`declare`/
+  `define`); the runtime `type_of(any)` now reads the tag AS a `.type_value` (no re-box); (c)
+  expr_typer infers a bare type-name expr as `.type_value` (with a `is_raw` backtick exemption —
+  `` `string `` is a value, never the reserved type); (d) `reflectionArgIsType` accepts
+  `.type_value` OR `.any` (a reflection arg can be a bare Type OR a boxed Any — the over-narrow
+  `==.type_value` was the catastrophic-regression cause, caught + fixed); (e) the comptime
+  `switch_br` accepts a `.type_tag` discriminant (type-category match); (f) a bare function name
+  in a `Type` slot now lowers to `const_type(its real function type)` instead of a func-ref
+  (fixed a JIT crash — was a func-ref word read as a TypeId), keeping the old string-box path only
+  for genuine `Any` params; (g) the field-not-found diagnostic + `formatTypeName` render
+  `.type_value` as "Type". Fixed 3 unit tests asserting the old `.any` Type behavior.
+  **697/0 BOTH gates** + all 494 unit tests (EXIT=0). Gate ON stays green because the VM's
+  `kindOf(.type_value)` → `.unsupported` → bails CLEANLY to legacy (no silent-wrong) — the VM
+  doesn't model `Type` values YET (next step), but parity holds. Regenerated 24 snapshots (22
+  `.ir` const_type-shape; 2 `.stderr` Any→Type — diff reviewed, only the intended changes). On
+  `reify`. **Next:** model `.type_value` natively in the VM (`kindOf` → word, `const_type` → word
+  = `TypeId.index()`, `regToValue` word → `.type_tag`) for COVERAGE, then port the WRITE side into
+  `callCompilerFn` + a real lowering-time Context → the first HANDLED lowering-time type-fn.
 - **Phase 3 P3.4 step 2 (VM plan) — dedicated `Type` builtin TypeId: FOUNDATION landed (dead/additive) (2026-06-18).**
   Added `TypeId.type_value` (slot 19) + a matching `TypeInfo.type_value` variant + the builtins
   init entry — an **8-byte type handle distinct from the 16-byte boxed `.any`** (THE WALL). All

examples/expected/0149-types-int-numeric-limits-errors.stderr

@@ -4,7 +4,7 @@ error: type 'bool' has no '.max' — numeric limits apply only to integer and fl
 14 |     b := bool.max;
    |          ^^^^^^^^
 
-error: field 'min' not found on type 'Any'
+error: field 'min' not found on type 'Type'
   --> examples/0149-types-int-numeric-limits-errors.sx:15:10
    |
 15 |     s := MyStruct.min;

examples/expected/0160-types-float-numeric-limits-errors.stderr

@@ -28,7 +28,7 @@ error: type 'string' has no '.max' — numeric limits apply only to integer and
 24 |     e := string.max;
    |          ^^^^^^^^^^
 
-error: field 'epsilon' not found on type 'Any'
+error: field 'epsilon' not found on type 'Type'
   --> examples/0160-types-float-numeric-limits-errors.sx:25:10
    |
 25 |     f := MyStruct.epsilon;

src/backend/llvm/ops.zig

@@ -130,23 +130,15 @@ pub const Ops = struct {
     }
 
     pub fn emitConstType(self: Ops, tid: TypeId) void {
-        // Type values are Any-shaped pairs:
-        //   { tag = .any.index() (the meta-marker),
-        //     value = tid.index() }
-        // Lets storage in Any slots, struct fields,
-        // `Type`-typed vars, and slice elements all round-
-        // trip through the standard Any infrastructure.
-        // `case type:` in `any_to_string` matches on
-        // tag == `.any.index()`. Runtime `type_name(t)`
-        // extracts the value field and indexes into the
-        // type-name lookup table.
-        const any_ty = self.e.getAnyStructType();
-        const tag = c.LLVMConstInt(self.e.cached_i64, TypeId.any.index(), 0);
+        // A Type value is an 8-byte handle: a bare i64 carrying `tid.index()`
+        // (the `.type_value` builtin TypeId), distinct from the 16-byte boxed
+        // `.any`. Flowing a Type into an `Any` slot boxes it via the standard
+        // box-any coercion (`{ tag = .any.index(), value = tid }`); `case type:`
+        // in `any_to_string` then matches tag == `.any.index()`, and runtime
+        // `type_name(t)` reads the TypeId through `reflectArgTypeId` (`.bare`
+        // when the arg is `.type_value`, `.boxed` when it is an Any).
         const val = c.LLVMConstInt(self.e.cached_i64, tid.index(), 0);
-        var result = c.LLVMGetUndef(any_ty);
-        result = c.LLVMBuildInsertValue(self.e.builder, result, tag, 0, "ct.tag");
-        result = c.LLVMBuildInsertValue(self.e.builder, result, val, 1, "ct.val");
-        self.e.mapRef(result);
+        self.e.mapRef(val);
     }
 
     // ── Arithmetic ─────────────────────────────────────────
@@ -1341,11 +1333,11 @@ pub const Ops = struct {
     /// Resolve the `TypeId` (as a runtime `i64`) that a dynamic
     /// `type_name` / `type_is_unsigned` must operate on. A reflection
     /// builtin reads an `Any`'s runtime TYPE-TAG, never its raw payload:
-    ///   - `.bare`: a `Type` value already lowered to a bare i64 `TypeId`
-    ///     index (an unboxed direct call site) → the value itself.
+    ///   - `.bare`: a `Type` value (a `.type_value` arg) — a bare i64 `TypeId`
+    ///     index (e.g. `type_of(x)` directly) → the value itself.
     ///   - `.boxed`: an `Any` aggregate `{ tag, value }`. When the tag is
-    ///     `.any`, the box carries a *Type value* (the `{ .any, tid }` shape
-    ///     `const_type` / `type_of` produce) → the TypeId is the payload.
+    ///     `.type_value`, the box carries a *Type value* (a `Type` boxed into an
+    ///     `Any`, `{ .type_value, tid }`) → the TypeId is the payload.
     ///     Otherwise the box carries a *runtime value* whose type IS the tag
     ///     → use the tag as the TypeId. This is what makes `type_name(av)`
     ///     for `av : Any = 6` report `i64` (the held value's type), while
@@ -1360,8 +1352,8 @@ pub const Ops = struct {
             .boxed => blk: {
                 const tag = c.LLVMBuildExtractValue(self.e.builder, arg_val, 0, "refl.tag");
                 const payload = c.LLVMBuildExtractValue(self.e.builder, arg_val, 1, "refl.val");
-                const any_tag = c.LLVMConstInt(self.e.cached_i64, @intCast(TypeId.any.index()), 0);
-                const holds_type = c.LLVMBuildICmp(self.e.builder, c.LLVMIntEQ, tag, any_tag, "refl.istype");
+                const type_tag = c.LLVMConstInt(self.e.cached_i64, @intCast(TypeId.type_value.index()), 0);
+                const holds_type = c.LLVMBuildICmp(self.e.builder, c.LLVMIntEQ, tag, type_tag, "refl.istype");
                 break :blk c.LLVMBuildSelect(self.e.builder, holds_type, payload, tag, "refl.tid");
             },
         };

src/ir/calls.test.zig

@@ -86,7 +86,7 @@ test "calls: builtin and reflection result types, unknown fallthrough" {
         .{ .name = "error_tag_name", .want = .string },
         .{ .name = "is_comptime", .want = .bool },
         .{ .name = "is_flags", .want = .bool },
-        .{ .name = "type_of", .want = .any },
+        .{ .name = "type_of", .want = .type_value },
         .{ .name = "field_value", .want = .any },
         .{ .name = "__interp_print_frames", .want = .void },
         // A math builtin with a non-`f32` argument widens to `f64` (the int

src/ir/calls.zig

@@ -154,7 +154,7 @@ pub const CallResolver = struct {
                 return refl(bare_name, self.l.module.types.findByName(self.l.module.types.internString("TraceFrame")) orelse .unresolved);
             if (std.mem.eql(u8, bare_name, "is_flags")) return refl(bare_name, .bool);
             if (std.mem.eql(u8, bare_name, "type_is_unsigned")) return refl(bare_name, .bool);
-            if (std.mem.eql(u8, bare_name, "type_of")) return refl(bare_name, .any);
+            if (std.mem.eql(u8, bare_name, "type_of")) return refl(bare_name, .type_value);
             if (std.mem.eql(u8, bare_name, "field_value")) return refl(bare_name, .any);
             // Plain bare same-name flat collision (R5 §C): route through the ONE
             // author producer `selectedFreeAuthor` so `plan` types the call as the

src/ir/expr_typer.zig

@@ -306,8 +306,11 @@ pub const ExprTyper = struct {
                 }
                 // A bare type name (alias like `Vec4`, struct name, or
                 // builtin primitive) referenced in expression position
-                // is a Type value — IR type `.any`.
-                if (self.l.isKnownTypeName(id.name)) return .any;
+                // is a Type value — IR type `.type_value` (8-byte handle). A
+                // BACKTICK raw identifier (`` `string ``) is explicitly a value
+                // binding, never the reserved type — so it never resolves here as a
+                // Type (it was found in scope above, or is genuinely unresolved).
+                if (!id.is_raw and self.l.isKnownTypeName(id.name)) return .type_value;
                 return .unresolved;
             },
             .type_expr => |te| {
@@ -318,8 +321,8 @@ pub const ExprTyper = struct {
                     }
                 }
                 // A bare type name in expression position (e.g. `i64`,
-                // `Point`, `*u8`) is a Type value — IR type `.any`.
-                if (self.l.isKnownTypeName(te.name)) return .any;
+                // `Point`, `*u8`) is a Type value — IR type `.type_value`.
+                if (self.l.isKnownTypeName(te.name)) return .type_value;
                 return .unresolved;
             },
             .enum_literal => {

src/ir/interp.test.zig

@@ -812,7 +812,10 @@ test "comptime: type_eq builtin on type_tag values" {
 // `av : Any = 6` (`{ tag = i64, value = 6 }`) must resolve to `i64`, NOT
 // `types[6]` (`u8`).
 test "reflect: reflectTypeId branches on the Any tag" {
-    const any_idx: i64 = @intCast(TypeId.any.index());
+    // The "Any holds a Type" meta-marker tag is `.type_value` (an Any boxing a
+    // Type value carries `{ tag = .type_value, value = tid }`), distinct from a
+    // boxed runtime value whose tag is the held value's own type.
+    const type_marker: i64 = @intCast(TypeId.type_value.index());
 
     // Native first-class Type value → the held TypeId directly.
     try std.testing.expectEqual(@as(?TypeId, .u64), (Value{ .type_tag = .u64 }).reflectTypeId());
@@ -827,13 +830,13 @@ test "reflect: reflectTypeId branches on the Any tag" {
     try std.testing.expectEqual(@as(?TypeId, .u32), (Value{ .aggregate = &held_u32 }).reflectTypeId());
 
     // Any holding a TYPE value (the `type_of(x)` / `const_type` shape):
-    // `{ tag = .any, value = u64 }` → u64 (the payload). Payload as a plain
+    // `{ tag = .type_value, value = u64 }` → u64 (the payload). Payload as a plain
     // int (the runtime box shape) ...
-    var held_type_int = [_]Value{ .{ .int = any_idx }, .{ .int = @intCast(TypeId.u64.index()) } };
+    var held_type_int = [_]Value{ .{ .int = type_marker }, .{ .int = @intCast(TypeId.u64.index()) } };
     try std.testing.expectEqual(@as(?TypeId, .u64), (Value{ .aggregate = &held_type_int }).reflectTypeId());
 
     // ... and payload as a `.type_tag` (the comptime box shape) → same result.
-    var held_type_tag = [_]Value{ .{ .int = any_idx }, .{ .type_tag = .u64 } };
+    var held_type_tag = [_]Value{ .{ .int = type_marker }, .{ .type_tag = .u64 } };
     try std.testing.expectEqual(@as(?TypeId, .u64), (Value{ .aggregate = &held_type_tag }).reflectTypeId());
 
     // Neither shape → null (the caller bails loudly, never guesses a TypeId).

src/ir/interp.zig

@@ -107,7 +107,7 @@ pub const Value = union(enum) {
             const fields = self.aggregate;
             if (fields.len >= 2) {
                 const tag = fields[0].asInt() orelse return null;
-                if (tag == @as(i64, @intCast(TypeId.any.index()))) {
+                if (tag == @as(i64, @intCast(TypeId.type_value.index()))) {
                     if (fields[1].asTypeId()) |t| return t;
                     if (fields[1].asInt()) |iv| return TypeId.fromIndex(@intCast(iv));
                     return null;
@@ -927,7 +927,16 @@ pub const Interpreter = struct {
                 switch (base) {
                     .aggregate => |fields| {
                         if (fa.field_index >= fields.len) return error.OutOfBounds;
-                        return .{ .value = fields[fa.field_index] };
+                        const field_val = fields[fa.field_index];
+                        // `type_of(an_any)` lowers to `struct_get(any, 0, .type_value)`:
+                        // the Any's field 0 is the held value's type id (a plain
+                        // `.int`), but the SSA result type is `.type_value`, so yield a
+                        // first-class `.type_tag` Value (a `.type_value`-typed value is
+                        // always a `.type_tag` in the interp — mirrors `const_type`).
+                        if (instruction.ty == .type_value) {
+                            if (field_val.asInt()) |iv| return .{ .value = .{ .type_tag = TypeId.fromIndex(@intCast(iv)) } };
+                        }
+                        return .{ .value = field_val };
                     },
                     .string => |s| {
                         // String as fat pointer: field 0 = ptr (string), field 1 = len
@@ -942,12 +951,12 @@ pub const Interpreter = struct {
                     },
                     .type_tag => |tid| {
                         // A first-class Type value is the comptime form of the
-                        // runtime Any-Type aggregate `{ tag=.any, value=tid }`
+                        // runtime Any-Type aggregate `{ tag=.type_value, value=tid }`
                         // (see `const_type` lowering in buildPackSliceValue).
                         // `type_of(any_holding_a_Type)` lowers to struct_get
                         // field 0, expecting that runtime layout — mirror it so
-                        // field 0 reads the `.any` tag and field 1 the type id.
-                        if (fa.field_index == 0) return .{ .value = .{ .int = @intCast(TypeId.any.index()) } };
+                        // field 0 reads the `.type_value` tag and field 1 the type id.
+                        if (fa.field_index == 0) return .{ .value = .{ .int = @intCast(TypeId.type_value.index()) } };
                         if (fa.field_index == 1) return .{ .value = .{ .type_tag = tid } };
                         return error.OutOfBounds;
                     },
@@ -1080,7 +1089,12 @@ pub const Interpreter = struct {
                 return .branch;
             },
             .switch_br => |sb| {
-                const operand = frame.getRef(sb.operand).asInt() orelse return error.TypeError;
+                // A type-category match (`type_of(x) == { case int: … }`)
+                // switches on a Type value — a `.type_tag` Value whose discriminant
+                // is its TypeId index; an enum/error switch uses a plain int.
+                const sb_val = frame.getRef(sb.operand);
+                const operand = sb_val.asInt() orelse
+                    (if (sb_val.asTypeId()) |t| @as(i64, @intCast(t.index())) else return error.TypeError);
                 for (sb.cases) |case| {
                     if (operand == case.value) {
                         const args = self.alloc.alloc(Value, case.args.len) catch return error.CannotEvalComptime;

src/ir/lower/call.zig

@@ -1690,7 +1690,7 @@ pub fn tryLowerReflectionCall(self: *Lowering, name: []const u8, c: *const ast.C
         // self-reference resolves); the interp's `declare` returns that slot.
         const name_ref = self.lowerExpr(c.args[0]);
         const args_owned = self.alloc.dupe(Ref, &.{name_ref}) catch return Ref.none;
-        return self.builder.callBuiltin(.declare, args_owned, .any);
+        return self.builder.callBuiltin(.declare, args_owned, .type_value);
     }
     if (std.mem.eql(u8, name, "define")) {
         // Comptime type-construction primitive: complete a declare()'d slot
@@ -1711,7 +1711,7 @@ pub fn tryLowerReflectionCall(self: *Lowering, name: []const u8, c: *const ast.C
         const args_owned = self.alloc.dupe(Ref, &.{ handle_ref, info_ref }) catch return Ref.none;
         // define returns the (now-completed) handle as a `Type` value, so the
         // one-shot constructor form chains: `T :: define(declare(), info)`.
-        return self.builder.callBuiltin(.define, args_owned, .any);
+        return self.builder.callBuiltin(.define, args_owned, .type_value);
     }
     if (std.mem.eql(u8, name, "type_info")) {
         // Comptime reflection-into-data: reflect a type INTO a `TypeInfo`
@@ -1935,16 +1935,15 @@ pub fn tryLowerReflectionCall(self: *Lowering, name: []const u8, c: *const ast.C
         } }, .any);
     }
     if (std.mem.eql(u8, name, "type_of")) {
-        // type_of(val) — produce a Type value (.any-typed aggregate).
+        // type_of(val) — produce a Type value (`.type_value`, a bare i64 handle).
         if (c.args.len < 1) return self.builder.constType(.void);
         const arg_ty = self.inferExprType(c.args[0]);
         if (arg_ty == .any) {
-            // Runtime: extract tag, rebuild Any with `{.any, tag}` so
-            // the returned value carries Type semantics (tag field
-            // says ".any" → the value field holds the type id).
+            // Runtime: the held value's type is the Any's tag (field 0). Read it
+            // out AS the 8-byte `.type_value` handle — type_of of a runtime Any
+            // names the held value's type, so the tag IS the type id.
             const val = self.lowerExpr(c.args[0]);
-            const tag_val = self.builder.structGet(val, 0, .i64);
-            return self.builder.boxAny(tag_val, .any);
+            return self.builder.structGet(val, 0, .type_value);
         } else {
             return self.builder.constType(arg_ty);
         }
@@ -1988,13 +1987,17 @@ pub fn tryLowerReflectionCall(self: *Lowering, name: []const u8, c: *const ast.C
 /// Strict `$T: Type` classification shared by the 7 type-introspection
 /// builtins. An argument denotes a type iff it is a spelled /
 /// compile-time type or generic type parameter (the `isStaticTypeArg`
-/// shapes), or a runtime `Type` value — which is `.any`-typed at
+/// shapes), or a runtime `Type` value — which is `.type_value`-typed at
 /// runtime (`type_of(x)`, a `[]Type` element `list[i]`, a `Type`-typed
 /// local / field / param). Any other expression — a value of type
 /// i64 / f64 / bool / a struct — is NOT a type.
 pub fn reflectionArgIsType(self: *Lowering, arg: *const Node) bool {
     if (self.isStaticTypeArg(arg)) return true;
-    return self.inferExprType(arg) == .any;
+    // Either a bare `Type` value (`.type_value`) or an `Any` that may hold a Type
+    // — the boxed reflection path (`case type: type_name(val)` where `val: Any`,
+    // the runtime tag deciding). Both are valid reflection arguments.
+    const ty = self.inferExprType(arg);
+    return ty == .type_value or ty == .any;
 }
 
 /// Guard for the type-introspection builtins (`size_of`, `align_of`,

src/ir/lower/expr.zig

@@ -1881,8 +1881,12 @@ pub fn lowerExpr(self: *Lowering, node: *const Node) Ref {
                         d.addFmt(.err, node.span, "'{s}' is not visible; #import the module that declares it", .{eff_fn_name});
                     break :blk self.emitError(eff_fn_name, node.span);
                 }
-                // Type-as-value: if target is Any (Type variable), produce a type name string
-                if (self.target_type == .any) {
+                // Type-as-value: a bare function name in a `Type` (`.type_value`)
+                // slot is its FUNCTION TYPE — `const_type(() -> R)` — so it prints
+                // / reflects as the real function type, not a func-ref. For a
+                // genuine `Any` param the old behavior is kept (a formatted
+                // type-name string boxed as Any).
+                if (self.target_type == .any or self.target_type == .type_value) {
                     const fd_any: ?*const ast.FnDecl = self.program_index.fn_ast_map.get(eff_fn_name) orelse fd_blk: {
                         switch (self.selectPlainCallableAuthor(id.name, self.current_source_file.?)) {
                             .func => |sf| break :fd_blk sf.decl,
@@ -1890,6 +1894,13 @@ pub fn lowerExpr(self: *Lowering, node: *const Node) Ref {
                         }
                     };
                     if (fd_any) |fd| {
+                        if (self.target_type == .type_value) {
+                            var param_ids = std.ArrayList(TypeId).empty;
+                            defer param_ids.deinit(self.alloc);
+                            for (fd.params) |p| param_ids.append(self.alloc, self.resolveParamType(&p)) catch {};
+                            const fn_tid = self.module.types.functionType(param_ids.items, self.resolveReturnType(fd));
+                            break :blk self.builder.constType(fn_tid);
+                        }
                         const fn_type_str = self.formatFnTypeString(fd);
                         const sid = self.module.types.internString(fn_type_str);
                         const str = self.builder.constString(sid);

src/ir/lower/generic.zig

@@ -438,6 +438,7 @@ pub fn formatTypeName(self: *Lowering, ty: TypeId) []const u8 {
     if (ty == .void) return "void";
     if (ty == .string) return "string";
     if (ty == .any) return "Any";
+    if (ty == .type_value) return "Type";
     if (ty == .usize) return "usize";
     if (ty == .isize) return "isize";
 
@@ -665,7 +666,9 @@ pub fn resolveTypeCategoryTags(self: *Lowering, name: []const u8) []const u64 {
         return tags.items;
     }
     if (std.mem.eql(u8, name, "type") or std.mem.eql(u8, name, "Type")) {
-        tags.append(self.alloc, TypeId.any.index()) catch {};
+        // A Type value's runtime tag is `.type_value` (was `.any` when Type and
+        // Any shared a TypeId) — so `case type:` matches an Any holding a Type.
+        tags.append(self.alloc, TypeId.type_value.index()) catch {};
         return tags.items;
     }
 

src/ir/module.zig

@@ -454,11 +454,12 @@ pub const Builder = struct {
     /// fail loudly rather than silently materialise the TypeId as an
     /// int.
     pub fn constType(self: *Builder, tid: TypeId) Ref {
-        // Type values are Any-shaped at runtime —
-        // `{ tag = .any.index() (the meta-marker), value = tid }`.
-        // Matches `Type → .any` in `type_bridge`. The interp keeps
-        // the high-fidelity `.type_tag` Value for comptime ops.
-        return self.emit(.{ .const_type = tid }, .any);
+        // A Type value is its own 8-byte builtin handle (`.type_value`), a bare
+        // i64 carrying `tid.index()` — distinct from the 16-byte boxed `.any`.
+        // Flowing it into an `Any` slot boxes it (`{ tag = .any.index(), value =
+        // tid }`) via the standard box-any coercion. The interp keeps the
+        // high-fidelity `.type_tag` Value for comptime ops.
+        return self.emit(.{ .const_type = tid }, .type_value);
     }
 
     // ── Arithmetic ──────────────────────────────────────────────────

src/ir/type_resolver.test.zig

@@ -37,7 +37,7 @@ test "TypeResolver.resolvePrimitive maps builtin keywords, null otherwise" {
     try std.testing.expectEqual(@as(?TypeId, .f64), TypeResolver.resolvePrimitive("f64"));
     try std.testing.expectEqual(@as(?TypeId, .void), TypeResolver.resolvePrimitive("void"));
     try std.testing.expectEqual(@as(?TypeId, .any), TypeResolver.resolvePrimitive("Any"));
-    try std.testing.expectEqual(@as(?TypeId, .any), TypeResolver.resolvePrimitive("Type"));
+    try std.testing.expectEqual(@as(?TypeId, .type_value), TypeResolver.resolvePrimitive("Type"));
     try std.testing.expectEqual(@as(?TypeId, .usize), TypeResolver.resolvePrimitive("usize"));
     try std.testing.expectEqual(@as(?TypeId, .isize), TypeResolver.resolvePrimitive("isize"));
     try std.testing.expectEqual(@as(?TypeId, .noreturn), TypeResolver.resolvePrimitive("noreturn"));

src/ir/type_resolver.zig

@@ -58,10 +58,11 @@ pub const TypeResolver = struct {
         if (std.mem.eql(u8, name, "cstring")) return .cstring;
         if (std.mem.eql(u8, name, "void")) return .void;
         if (std.mem.eql(u8, name, "Any")) return .any;
-        // `Type` values are runtime-representable as Any-shaped pairs
-        // `{ tag = .any.index(), value = TypeId.index() }`, so `Type` maps to
-        // `.any` and routes through the existing Any infrastructure.
-        if (std.mem.eql(u8, name, "Type")) return .any;
+        // A `Type` value is its own 8-byte builtin handle (`.type_value`), DISTINCT
+        // from the 16-byte boxed `.any`. Flowing a `Type` into an `Any` slot boxes
+        // it (`{ tag = .any.index(), value = TypeId.index() }`) via the standard
+        // box-any coercion; reflection reads it back through `reflectArgRepr`.
+        if (std.mem.eql(u8, name, "Type")) return .type_value;
         if (std.mem.eql(u8, name, "noreturn")) return .noreturn;
         if (std.mem.eql(u8, name, "usize")) return .usize;
         if (std.mem.eql(u8, name, "isize")) return .isize;