diff --git a/CHANGELOG.md b/CHANGELOG.md
index a97c15e..84208c5 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -8,6 +8,10 @@
 - `throughput` write subcommands (`set`/`manual`/`autoscale`) now accept `--dry-run` to preview the change — reporting current vs. planned mode and RU/s as JSON (and a table interactively) — without applying it or prompting for confirmation. A first slice of dry-run mode (item G1). ([#164](https://github.com/Azure/CosmosDBShell/issues/164))
 - **`--dry-run` for destructive delete commands.** `rm`, `rmcon`, `rmdb`, and `delete` accept `--dry-run` to preview the effect without deleting anything: `rm` reports how many items match the pattern, and `rmcon`/`rmdb` report the container or database that would be removed. No confirmation prompt is shown and no changes are made. ([#156](https://github.com/Azure/CosmosDBShell/issues/156))
 
+### Improvements
+
+- **Structured (JSON) tool results for MCP.** MCP tool results now carry the machine-readable JSON payload (`result`/`outputText`/`error` plus `currentLocation`) as first-class `structuredContent` in addition to the existing JSON text block, so agents can consume structured results directly. The two representations are kept byte-for-byte equivalent, and text-only clients are unaffected. ([#154](https://github.com/Azure/CosmosDBShell/issues/154))
+
 ## 1.1.115-preview — 2026-07-01
 
 A large feature cycle on top of 1.1.4-preview. The shell gains a stack of new commands — configurable **color themes**, a native **`filter`** language, change-feed **`watch`**, **`index`** and **`throughput`** management, bulk **`import`/`export`**, and server-side **`sproc`/`udf`/`trigger`** programming — plus a reworked **`info`** command (formerly `settings`) with usage statistics and JSON output, first-class observability through **`--diagnostics`** and **`--otel`**, and hardening of the MCP server.
diff --git a/CosmosDBShell.Tests/McpResponseFactoryTests.cs b/CosmosDBShell.Tests/McpResponseFactoryTests.cs
index 99f92a2..4a9088b 100644
--- a/CosmosDBShell.Tests/McpResponseFactoryTests.cs
+++ b/CosmosDBShell.Tests/McpResponseFactoryTests.cs
@@ -103,4 +103,45 @@ public void CreateSuccess_WhenDisconnected_UsesNullCurrentLocation()
         Assert.False(result.IsError);
         Assert.Equal(JsonValueKind.Null, document.RootElement.GetProperty("currentLocation").ValueKind);
     }
+
+    [Fact]
+    public void CreateSuccess_PopulatesStructuredContentMatchingTextBlock()
+    {
+        var commandState = new CommandState
+        {
+            Result = new ShellJson(JsonSerializer.SerializeToElement(new
+            {
+                connected = true,
+            })),
+        };
+
+        var result = McpResponseFactory.CreateSuccess(commandState, new ContainerState("TestContainer", "TestDatabase", null!));
+        var text = Assert.IsType<TextContentBlock>(Assert.Single(result.Content)).Text;
+
+        Assert.NotNull(result.StructuredContent);
+        var structured = result.StructuredContent!.Value;
+
+        // The structured payload and the text rendering must stay in lockstep so clients
+        // that read either representation observe the same contract.
+        Assert.Equal(text, structured.GetRawText());
+        Assert.True(structured.GetProperty("result").GetProperty("connected").GetBoolean());
+        Assert.Equal("/TestDatabase/TestContainer", structured.GetProperty("currentLocation").GetString());
+    }
+
+    [Fact]
+    public void CreateError_PopulatesStructuredContentMatchingTextBlock()
+    {
+        var result = McpResponseFactory.CreateError("boom", new DatabaseState("TestDatabase", null!));
+        var text = Assert.IsType<TextContentBlock>(Assert.Single(result.Content)).Text;
+
+        Assert.True(result.IsError);
+        Assert.NotNull(result.StructuredContent);
+        var structured = result.StructuredContent!.Value;
+
+        // The structured payload and the text rendering must stay in lockstep so clients
+        // that read either representation observe the same contract.
+        Assert.Equal(text, structured.GetRawText());
+        Assert.Equal("boom", structured.GetProperty("error").GetString());
+        Assert.Equal("/TestDatabase", structured.GetProperty("currentLocation").GetString());
+    }
 }
\ No newline at end of file
diff --git a/CosmosDBShell/Azure.Data.Cosmos.Shell.Mcp/McpResponseFactory.cs b/CosmosDBShell/Azure.Data.Cosmos.Shell.Mcp/McpResponseFactory.cs
index 698cdc7..c7c4249 100644
--- a/CosmosDBShell/Azure.Data.Cosmos.Shell.Mcp/McpResponseFactory.cs
+++ b/CosmosDBShell/Azure.Data.Cosmos.Shell.Mcp/McpResponseFactory.cs
@@ -57,13 +57,22 @@ private static CallToolResult CreateResponse(JsonObject payload, State shellStat
     {
         payload["currentLocation"] = GetCurrentLocation(shellState);
 
+        // Serialize the payload exactly once. The text content block reuses the structured
+        // element's raw JSON so the two representations are inherently byte-for-byte identical
+        // and no second serializer can drift out of sync.
+        var structuredContent = JsonSerializer.SerializeToElement(payload, JsonOptions);
+
         return new CallToolResult
         {
+            // Emit the machine-readable payload as first-class structured content while
+            // retaining an equivalent text rendering so that clients that only read text
+            // content blocks continue to work.
+            StructuredContent = structuredContent,
             Content =
             [
                 new TextContentBlock
                 {
-                    Text = payload.ToJsonString(JsonOptions),
+                    Text = structuredContent.GetRawText(),
                 }
             ],
             IsError = isError,
diff --git a/docs/mcp.md b/docs/mcp.md
index d29fc40..d8f4d00 100644
--- a/docs/mcp.md
+++ b/docs/mcp.md
@@ -70,3 +70,24 @@ Your MCP client may use a remote LLM. Command outputs, query results, and file c
 - [ ] Review and approve destructive operations manually
 - [ ] Don't share secrets (keys, PII) in prompts or outputs
 - [ ] Disable MCP mode when not actively using it
+
+## Tool Results
+
+Every tool result carries the same machine-readable JSON payload in two places:
+
+- **`structuredContent`** — the payload as first-class structured content, for clients that consume MCP structured results.
+- **A text content block** — the identical payload serialized as JSON text, so clients that only read text content blocks continue to work.
+
+Both representations are always byte-for-byte equivalent.
+
+### Payload shape
+
+| Field | When present | Description |
+| ----- | ------------ | ----------- |
+| `result` | Successful commands that produce output | The command result as JSON (objects, arrays, or a scalar). Text-only results are represented as a JSON string. |
+| `outputText` | CSV output commands with non-empty text | The CSV rendering of the result. Omitted when the CSV output is empty or whitespace. |
+| `error` | Failed commands | The error message. |
+| `currentLocation` | Always | The shell's current navigation path (for example `/MyDatabase/MyContainer`), or `null` when disconnected. |
+
+Successful results set `result` (and optionally `outputText`); failed results set `error` and mark the tool result as an error. `currentLocation` is always included so a client can track navigation state across calls.
+