diff --git a/docs/src/css/custom.css b/docs/src/css/custom.css
index 85adb3538..20c91db1e 100644
--- a/docs/src/css/custom.css
+++ b/docs/src/css/custom.css
@@ -19,7 +19,8 @@ table tr:nth-child(even) {
 }
 
 /* changing the links to blue for accessibility  */
-p a, .markdown a {
+p a,
+.markdown a {
   color: var(--slack-cloud-blue);
 }
 
@@ -53,7 +54,7 @@ a:hover {
 /* removing ToC line */
 .table-of-contents__left-border {
   border-left: none !important;
-} 
+}
 
 /* increasing name of SDK in sidebar */
 .sidebar-title {
@@ -64,8 +65,8 @@ a:hover {
 
 /* removing sidebar line and adding space to match ToC */
 .theme-doc-sidebar-container {
-    border-right: none !important;
-    margin-right: 2rem;
+  border-right: none !important;
+  margin-right: 2rem;
 }
 
 /* announcement bar up top */
@@ -112,17 +113,17 @@ html[data-theme="dark"] .navbar-github-link::before {
 
 /* Docs code bubbles */
 [data-theme="light"] {
-  --code-link-background: #CFE9FE; 
-  --code-link-text:  rgb(21, 50, 59);
+  --code-link-background: #cfe9fe;
+  --code-link-text: rgb(21, 50, 59);
 
-  --method-link-background: #CDEFC4;
+  --method-link-background: #cdefc4;
   --method-link-text: rgb(0, 41, 0);
 
-  --scope-link-background: #FBF3E0; 
+  --scope-link-background: #fbf3e0;
   --scope-link-text: rgb(63, 46, 0);
 
-  --event-link-background: #FDDDE3;
-  --event-link-text:  rgb(74, 21, 75);
+  --event-link-background: #fddde3;
+  --event-link-text: rgb(74, 21, 75);
 }
 
 [data-theme="dark"] {
@@ -130,28 +131,28 @@ html[data-theme="dark"] .navbar-github-link::before {
   --method-link-text: white;
   --scope-link-text: white;
   --event-link-text: white;
-  --code-link-background: #1AB9FF50;
-  --method-link-background: #41B65850;
-  --scope-link-background: #FCC00350;
-  --event-link-background: #E3066A50;
+  --code-link-background: #1ab9ff50;
+  --method-link-background: #41b65850;
+  --scope-link-background: #fcc00350;
+  --event-link-background: #e3066a50;
 }
 
 a code {
   background-color: var(--code-link-background);
-  color:  var(--code-link-text);
+  color: var(--code-link-text);
 }
 
 a[href^="https://api.slack.com/methods"] > code {
   background-color: var(--method-link-background);
-  color:  var(--method-link-text);
+  color: var(--method-link-text);
 }
 
 a[href^="https://api.slack.com/scopes"] > code {
   background-color: var(--scope-link-background);
-  color:  var(--scope-link-text);
+  color: var(--scope-link-text);
 }
 
 a[href^="https://api.slack.com/events"] > code {
   background-color: var(--event-link-background);
-  color:  var(--event-link-text);
-}
\ No newline at end of file
+  color: var(--event-link-text);
+}
diff --git a/src/Assistant.ts b/src/Assistant.ts
index 14d817d19..687d481de 100644
--- a/src/Assistant.ts
+++ b/src/Assistant.ts
@@ -9,8 +9,6 @@ import {
   type AssistantThreadContext,
   type AssistantThreadContextStore,
   DefaultThreadContextStore,
-  type GetThreadContextFn,
-  type SaveThreadContextFn,
 } from './AssistantThreadContextStore';
 import { AssistantInitializationError, AssistantMissingPropertyError } from './errors';
 import processMiddleware from './middleware/process';
@@ -30,14 +28,16 @@ export interface AssistantConfig {
  * Callback utilities
  */
 interface AssistantUtilityArgs {
-  getThreadContext: GetThreadContextFn;
-  saveThreadContext: SaveThreadContextFn;
+  getThreadContext: GetThreadContextUtilFn;
+  saveThreadContext: SaveThreadContextUtilFn;
   say: SayFn;
   setStatus: SetStatusFn;
   setSuggestedPrompts: SetSuggestedPromptsFn;
   setTitle: SetTitleFn;
 }
 
+type GetThreadContextUtilFn = () => Promise<AssistantThreadContext>;
+type SaveThreadContextUtilFn = () => Promise<void>;
 type SetStatusFn = (status: string) => Promise<AssistantThreadsSetStatusResponse>;
 
 type SetSuggestedPromptsFn = (
@@ -310,7 +310,7 @@ function createSay(args: AllAssistantMiddlewareArgs): SayFn {
   const { channelId: channel, threadTs: thread_ts, context } = extractThreadInfo(payload);
 
   return async (message: Parameters<SayFn>[0]) => {
-    const threadContext = context.channel_id ? context : await args.getThreadContext(args);
+    const threadContext = context.channel_id ? context : await args.getThreadContext();
     const postMessageArgument: ChatPostMessageArguments =
       typeof message === 'string' ? { text: message, channel, thread_ts } : { ...message, channel, thread_ts };
 
diff --git a/test/types/assistant.test-d.ts b/test/types/assistant.test-d.ts
new file mode 100644
index 000000000..1a1700056
--- /dev/null
+++ b/test/types/assistant.test-d.ts
@@ -0,0 +1,75 @@
+import { expectError, expectType } from 'tsd';
+import { type AllAssistantMiddlewareArgs, Assistant } from '../../src/Assistant';
+import type { AssistantThreadContext } from '../../src/AssistantThreadContextStore';
+
+// Constructor tests
+const asyncNoop = () => Promise.resolve();
+
+// missing required properties `threadStarted` and `userMessage`
+expectError(new Assistant({}));
+
+// missing required property `threadStarted`
+expectError(
+  new Assistant({
+    userMessage: asyncNoop,
+  }),
+);
+
+// missing required property `userMessage`
+expectError(
+  new Assistant({
+    threadStarted: asyncNoop,
+  }),
+);
+
+// happy construction
+expectType<Assistant>(
+  new Assistant({
+    threadStarted: asyncNoop,
+    userMessage: asyncNoop,
+  }),
+);
+
+// threadStarted tests
+new Assistant({
+  userMessage: asyncNoop,
+  threadStarted: async ({ saveThreadContext }) => {
+    expectType<void>(await saveThreadContext());
+    return Promise.resolve();
+  },
+});
+
+// userMessage tests
+new Assistant({
+  userMessage: async ({ getThreadContext }) => {
+    expectType<AssistantThreadContext>(await getThreadContext());
+    return Promise.resolve();
+  },
+  threadStarted: asyncNoop,
+});
+
+// threadContextChanged tests
+new Assistant({
+  userMessage: asyncNoop,
+  threadStarted: asyncNoop,
+  threadContextChanged: async ({ event }) => {
+    expectType<AssistantThreadContext>(event.assistant_thread.context);
+    return Promise.resolve();
+  },
+});
+
+// threadContextStore tests
+new Assistant({
+  threadContextStore: {
+    get: async (args) => {
+      expectType<AllAssistantMiddlewareArgs>(args);
+      return Promise.resolve({});
+    },
+    save: async (args) => {
+      expectType<AllAssistantMiddlewareArgs>(args);
+      return Promise.resolve();
+    },
+  },
+  userMessage: asyncNoop,
+  threadStarted: asyncNoop,
+});