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docs/stored-procedures.md

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+# Stored Procedures
+
+Stored procedure support is available through `db.Procedures` when `DynamicDatabaseOptions.SupportStoredProcedures` is enabled.
+
+## Basic Invocation
+
+```csharp
+var scalar = db.Procedures.sp_Exp_Scalar();
+var scalarTyped = db.Procedures.sp_Exp_Scalar<int>();
+```
+
+## Input, Output, Return Parameters
+
+Prefixes in argument names control parameter direction:
+
+- `out_` for output
+- `ret_` for return value
+- `both_` for input/output
+
+Example pattern:
+
+```csharp
+var res = db.Procedures.sp_Exp_SomeInputAndOutput<
+    string,
+    MyProcResult>(
+        Name: "G4g4r1n",
+        out_Result: new DynamicSchemaColumn { Size = 256 },
+        ret_Return: 0);
+```
+
+## Nested Procedure Names
+
+Dynamic member chaining builds qualified names:
+
+```csharp
+var res = db.Procedures.dbo.reporting.MyProc();
+```
+
+This resolves to `dbo.reporting.MyProc`.
+
+## Result Mapping
+
+If generic return types are provided, DynamORM attempts mapper-based projection into the target type.
+
+If output parameters are present, result payload is assembled from:
+
+- main scalar/resultset-derived value
+- output values
+- optional return value
+
+The behavior is implemented in `DynamORM/DynamicProcedureInvoker.cs` and documented in XML examples in `DynamORM/DynamicDatabase.cs`.