diff --git a/packages/components/src/components/chat/Chat.vue b/packages/components/src/components/chat/Chat.vue
index 261226044d..094439172e 100644
--- a/packages/components/src/components/chat/Chat.vue
+++ b/packages/components/src/components/chat/Chat.vue
@@ -77,21 +77,14 @@
 
 <script lang="ts">
 //@ts-nocheck
-import Vue, { PropType } from 'vue';
+import Vue from 'vue';
 import VUserMessage from '@/components/chat/UserMessage.vue';
 import VChatInput from '@/components/chat/ChatInput.vue';
 import VAppMapNavieLogo from '@/assets/appmap-full-logo.svg';
 import VButton from '@/components/Button.vue';
 import { AI } from '@appland/client';
 import { ExplainRpc, NavieRpc } from '@appland/rpc';
-
-export type CodeSelection = {
-  path: string;
-  lineStart: number;
-  lineEnd: number;
-  code: string;
-  language: string;
-};
+import { CodeSelection } from './CodeSelection';
 
 export interface ITool {
   title: string;
@@ -237,8 +230,34 @@ export default {
           const userMessage = this.addUserMessage(content);
           if (codeSelection && !populatedCodeSelection) {
             populatedCodeSelection = true;
-            // TODO: There's some mismatch here between what the UI shows & what's in the thread data.
-            userMessage.codeSelections = [codeSelection];
+
+            let parsedCodeSelections: CodeSelection[];
+            try {
+              // Code selections are stored natively as a CodeSelection object, but restored from
+              // serialization as a string.
+              parsedCodeSelections = JSON.parse(codeSelection);
+            } catch {
+              // Issue a warning
+              console.warn('Code selection is not valid JSON');
+
+              // If the codeSelection is not valid JSON, it's likely a string.
+              // This is a temporary fix to handle the string case.
+              parsedCodeSelections = [
+                {
+                  content: codeSelection,
+                },
+              ];
+            }
+            userMessage.codeSelections = parsedCodeSelections;
+
+            if (typeof codeSelection === 'string') {
+              const codeSelectionObj: CodeSelection = {
+                content: codeSelection,
+              };
+              userMessage.codeSelections = [codeSelectionObj];
+            } else {
+              userMessage.codeSelections = [codeSelection];
+            }
           }
         }
         if (exchange.answer) {
@@ -310,11 +329,7 @@ export default {
       const userMessage = this.addUserMessage(message);
       userMessage.codeSelections = this.codeSelections;
 
-      this.sendMessage(
-        message,
-        this.codeSelections.map((s) => s.code),
-        this.appmaps
-      );
+      this.sendMessage(message, this.codeSelections, this.appmaps);
 
       this.codeSelections = [];
     },
diff --git a/packages/components/src/components/chat/CodeSelection.ts b/packages/components/src/components/chat/CodeSelection.ts
new file mode 100644
index 0000000000..fabffe576c
--- /dev/null
+++ b/packages/components/src/components/chat/CodeSelection.ts
@@ -0,0 +1,7 @@
+export type CodeSelection = {
+  path: string;
+  lineStart: number;
+  lineEnd: number;
+  code: string;
+  language: string;
+};
diff --git a/packages/components/src/pages/ChatSearch.vue b/packages/components/src/pages/ChatSearch.vue
index dd2f28f8cc..7b31304ec7 100644
--- a/packages/components/src/pages/ChatSearch.vue
+++ b/packages/components/src/pages/ChatSearch.vue
@@ -118,7 +118,8 @@ import VPopper from '@/components/Popper.vue';
 import VContext from '@/components/chat-search/Context.vue';
 import VLlmConfiguration from '@/components/chat-search/LlmConfiguration.vue';
 import VPinnedItems from '@/components/chat-search/PinnedItems.vue';
-import type { CodeSelection, ITool } from '@/components/chat/Chat.vue';
+import type { ITool } from '@/components/chat/Chat.vue';
+import type { CodeSelection } from '@/components/chat/CodeSelection';
 import VChat from '@/components/chat/Chat.vue';
 import { getNextHandle } from '@/components/chat/Handle';
 import type { PinEvent, PinFile } from '@/components/chat/PinEvent';
@@ -469,7 +470,11 @@ export default {
       // and emit a stop event.
       this.ask?.stop();
     },
-    async sendMessage(message: string, codeSelections: string[] = [], appmaps: string[] = []) {
+    async sendMessage(
+      message: string,
+      codeSelections: CodeSelection[] = [],
+      appmaps: string[] = []
+    ) {
       this.ask = this.rpcClient.explain();
       this.searching = true;
       this.lastStatusLabel = undefined;
@@ -562,35 +567,51 @@ export default {
 
         const userProvidedContext: ExplainRpc.UserContextItem[] = [];
         if (this.pinnedItems.length > 0) {
-          userProvidedContext.push(
-            ...this.pinnedItems.map((p) => {
-              if (p.type === 'file') {
-                return {
-                  type: 'file',
-                  location: p.location,
-                };
-              } else {
-                return {
-                  type: 'code-snippet',
-                  location: p.location,
-                  content: p.content,
-                };
-              }
-            })
-          );
+          const pinnedItemContextItems = this.pinnedItems.map((p) => {
+            if (p.type === 'file') {
+              return {
+                type: 'file',
+                location: p.location,
+              };
+            } else {
+              return {
+                type: 'code-snippet',
+                location: p.location,
+                content: p.content,
+              };
+            }
+          });
+          userProvidedContext.push(...pinnedItemContextItems);
         }
 
         if (codeSelections.length > 0) {
-          userProvidedContext.push(
-            ...codeSelections.map((c) => ({
+          const codeSelectionContextItems = codeSelections.map((c) => {
+            const result: ExplainRpc.UserContextItem = {
               type: 'code-selection',
-              content: c,
-            }))
-          );
-        }
-        if (userProvidedContext.length > 0) {
-          explainRequest.codeSelection = userProvidedContext;
+              content: c.code,
+            };
+            if (c.path) {
+              const tokens = [c.path];
+              const range = [];
+              if (c.lineStart) {
+                range.push(c.lineStart);
+                if (c.lineEnd && c.lineEnd !== c.lineStart) {
+                  range.push(c.lineEnd);
+                }
+              }
+              if (range.length) {
+                tokens.push(range.join('-'));
+              }
+              result.location = tokens.join(':');
+            }
+
+            return result;
+          });
+          userProvidedContext.push(...codeSelectionContextItems);
         }
+
+        if (userProvidedContext.length > 0) explainRequest.codeSelection = userProvidedContext;
+
         const threadId = this.$refs.vchat.threadId || this.threadId;
         this.ask.explain(explainRequest, threadId).catch(onError);
       });
diff --git a/packages/components/src/stories/ChatInput.stories.js b/packages/components/src/stories/ChatInput.stories.js
index 93af64ba1a..ecde55c94b 100644
--- a/packages/components/src/stories/ChatInput.stories.js
+++ b/packages/components/src/stories/ChatInput.stories.js
@@ -15,6 +15,7 @@ const Template = (args, { argTypes }) => ({
     this.$nextTick(() => {
       const poppers = this.$el.querySelectorAll('.popper');
       poppers.forEach((popper) => {
+        // eslint-disable-next-line no-underscore-dangle
         const popperComponent = popper.__vue__;
         if (popperComponent) {
           popperComponent.visibleOverride = args.showTooltip;
diff --git a/packages/components/tests/unit/chat/ChatComponent.spec.js b/packages/components/tests/unit/chat/ChatComponent.spec.js
index 3de737ecff..d28e28aa95 100644
--- a/packages/components/tests/unit/chat/ChatComponent.spec.js
+++ b/packages/components/tests/unit/chat/ChatComponent.spec.js
@@ -195,7 +195,18 @@ describe('components/Chat.vue', () => {
 
       await wrapper.vm.$nextTick();
 
-      expect(sendMessage).toBeCalledWith('Hello from the user', [codeSelection.code], []);
+      expect(sendMessage).toBeCalledWith(
+        'Hello from the user',
+        [
+          {
+            code: '...',
+            lineEnd: 17,
+            lineStart: 6,
+            path: 'app/controllers/users_controller.rb',
+          },
+        ],
+        []
+      );
     });
 
     it('includes pending code snippets in the input area', async () => {