fix(slack): enforce agent API compatibility

Author: TheodoreSpeaks

apps/docs/content/docs/integrations/slack.mdx

@@ -803,6 +803,29 @@ Get a stable permalink URL to a specific Slack message.
 | `channel` | string | Channel ID containing the message |
 | `permalink` | string | The permalink URL to the message |
 
+### Slack Set Suggested Prompts
+
+Set the clickable suggested prompts shown in a Slack assistant thread (the prompt chips in an AI app).
+
+#### Input
+
+| Parameter | Type | Required | Description |
+| --------- | ---- | -------- | ----------- |
+| `authMethod` | string | No | Authentication method: oauth or bot_token |
+| `botToken` | string | No | Bot token for Custom Bot |
+| `channel` | string | Yes | Channel ID containing the assistant thread \(e.g., C1234567890 or D1234567890\) |
+| `threadTs` | string | Yes | Thread timestamp \(thread_ts\) of the assistant thread \(e.g., 1405894322.002768\) |
+| `prompts` | json | Yes | Array of prompts, each with a "title" \(shown on the chip\) and a "message" \(sent when clicked\). Max 4. |
+| `promptsTitle` | string | No | Optional heading for the prompt list, e.g. 'Suggested Prompts' |
+
+#### Output
+
+| Parameter | Type | Description |
+| --------- | ---- | ----------- |
+| `ok` | boolean | Whether the suggested prompts were set successfully |
+| `channel` | string | Channel ID the prompts were set on |
+| `threadTs` | string | Thread timestamp the prompts were set on |
+
 ### Slack Set Agent Suggested Prompts
 
 Set suggested prompts in Slack Agent View, optionally scoped to a specific thread.
@@ -850,7 +873,7 @@ Create or update the state of a Slack agent session associated with a thread.
 | `ok` | boolean | Whether Slack updated the agent session |
 | `status` | string | Requested agent session status |
 | `agentStatus` | string | Agent status recorded by Slack |
-| `title` | string | Current agent session title |
+| `title` | string | Current agent session title, or null when the session has no title |
 
 ### Slack Rename Agent Session
 
@@ -887,8 +910,8 @@ Start a streaming Slack message using Markdown or structured chunks.
 | `markdownText` | string | No | Initial Markdown content, mutually exclusive with chunks |
 | `chunks` | json | No | Initial structured Slack streaming chunks, mutually exclusive with Markdown |
 | `threadTs` | string | No | Parent thread timestamp when streaming a reply |
-| `recipientUserId` | string | No | Recipient user ID for a channel stream |
-| `recipientTeamId` | string | No | Recipient workspace ID for a channel stream |
+| `recipientUserId` | string | No | Recipient user ID, required with Recipient Team ID when channel is not a DM |
+| `recipientTeamId` | string | No | Recipient workspace ID, required with Recipient User ID when channel is not a DM |
 | `taskDisplayMode` | string | No | Task display mode: timeline or plan |
 | `iconEmoji` | string | No | Emoji used to customize the streaming agent identity |
 | `iconUrl` | string | No | Image URL used to customize the streaming agent identity |
@@ -914,8 +937,8 @@ Append Markdown or structured chunks to an active Slack stream.
 | `botToken` | string | No | Custom Slack bot token |
 | `channel` | string | Yes | Channel containing the streaming message |
 | `ts` | string | Yes | Timestamp returned by Start Stream |
-| `markdownText` | string | No | Markdown content to append, mutually exclusive with chunks |
-| `chunks` | json | No | Structured Slack streaming chunks, mutually exclusive with Markdown |
+| `markdownText` | string | No | Markdown content to append; provide this or chunks, but not both |
+| `chunks` | json | No | Structured Slack streaming chunks; provide this or Markdown Text, but not both |
 
 #### Output
 
@@ -952,10 +975,10 @@ Finalize an active Slack stream and return the resulting message.
 | `ts` | string | Finalized streaming message timestamp |
 | `message` | object | Final Slack message returned by chat.stopStream |
 |   ↳ `text` | string | Final message text |
-|   ↳ `bot_id` | string | Bot ID |
+|   ↳ `bot_id` | string | Bot ID, or null when Slack omits it |
 |   ↳ `ts` | string | Message timestamp |
 |   ↳ `type` | string | Message type |
-|   ↳ `subtype` | string | Message subtype |
+|   ↳ `subtype` | string | Message subtype, or null when the message has no subtype |
 
 ### Slack List Channels
 

apps/sim/app/workspace/[workspaceId]/integrations/components/connect-slack-bot-modal/connect-slack-bot-modal.tsx

@@ -70,9 +70,18 @@ function getAgentConfigurationError(
   if (prompts.some((prompt) => !prompt.title.trim() || !prompt.message.trim())) {
     return 'Every suggested prompt needs a title and message.'
   }
+  if (prompts.length > 4) {
+    return 'Slack Agent View supports at most four suggested prompts.'
+  }
   return null
 }
 
+function getAgentDescriptionError(description: string): string | null {
+  return description.trim().length > 300
+    ? 'Slack Agent View descriptions must be 300 characters or fewer.'
+    : null
+}
+
 interface ConnectSlackBotModalProps {
   open: boolean
   onOpenChange: (open: boolean) => void
@@ -152,10 +161,12 @@ export function ConnectSlackBotModal({
   // window.location.origin) so Slack's servers can reach it.
   const requestUrl = useMemo(() => buildSlackCustomBotRequestUrl(credentialId), [credentialId])
 
+  const descriptionError = getAgentDescriptionError(appDescription)
   const agentConfigurationError = getAgentConfigurationError(agentActions, suggestedPrompts)
+  const manifestConfigurationError = descriptionError ?? agentConfigurationError
 
   const manifestJson = useMemo(() => {
-    if (agentConfigurationError) return ''
+    if (manifestConfigurationError) return ''
     const managedUserAuthorization = selected.has(SLACK_MANAGED_USER_AUTHORIZATION_CAPABILITY.id)
       ? getSlackManagedUserAuthorizationManifestConfig(getBaseUrl())
       : undefined
@@ -169,7 +180,7 @@ export function ConnectSlackBotModal({
     })
     return JSON.stringify(manifest, null, 2)
   }, [
-    agentConfigurationError,
+    manifestConfigurationError,
     selected,
     appName,
     appDescription,
@@ -255,12 +266,16 @@ export function ConnectSlackBotModal({
       {/* Bot name is required so the credential name, the manifest app name, and
           uniqueness all use the user's choice — never the shared Slack team name
           fallback, which collides for a second bot in the same workspace. */}
-      <Wizard.Step title='Configure your bot' canAdvance={appName.trim().length > 0}>
+      <Wizard.Step
+        title='Configure your bot'
+        canAdvance={appName.trim().length > 0 && !descriptionError}
+      >
         <StepConfigure
           appName={appName}
           onAppNameChange={setAppName}
           appDescription={appDescription}
           onAppDescriptionChange={setAppDescription}
+          descriptionError={descriptionError}
           capabilityIds={capabilityIds}
           onCapabilityIdsChange={setCapabilityIds}
         />
@@ -319,6 +334,7 @@ interface StepConfigureProps {
   onAppNameChange: (next: string) => void
   appDescription: string
   onAppDescriptionChange: (next: string) => void
+  descriptionError: string | null
   capabilityIds: string[]
   onCapabilityIdsChange: (next: string[]) => void
 }
@@ -327,6 +343,7 @@ function StepConfigure({
   onAppNameChange,
   appDescription,
   onAppDescriptionChange,
+  descriptionError,
   capabilityIds,
   onCapabilityIdsChange,
 }: StepConfigureProps) {
@@ -355,7 +372,11 @@ function StepConfigure({
           onChange={(e) => onAppDescriptionChange(e.target.value)}
           placeholder="Optional — shown on the bot's Slack profile"
           maxLength={140}
+          error={Boolean(descriptionError)}
         />
+        {descriptionError && (
+          <p className='text-[var(--text-error)] text-caption'>{descriptionError}</p>
+        )}
       </div>
       <div className='flex flex-col gap-[9px]'>
         <Label className='text-[var(--text-muted)] text-small'>Additional permissions</Label>
@@ -517,7 +538,12 @@ function StepAgentView({
             </Button>
           </div>
         ))}
-        <Chip className='w-fit' leftIcon={Plus} onClick={addSuggestedPrompt}>
+        <Chip
+          className='w-fit'
+          leftIcon={Plus}
+          onClick={addSuggestedPrompt}
+          disabled={suggestedPrompts.length >= 4}
+        >
           Add suggested prompt
         </Chip>
       </div>

apps/sim/blocks/blocks/slack.test.ts

@@ -49,11 +49,14 @@ describe('Slack block release', () => {
 
   it('replaces legacy assistant operations with custom-bot Agent Sessions operations', () => {
     expect(operationIds()).toEqual(expect.arrayContaining(AGENT_OPERATION_IDS))
-    expect(operationIds()).not.toEqual(expect.arrayContaining(['set_status', 'set_title']))
+    for (const id of ['set_status', 'set_title']) {
+      expect(operationIds()).not.toContain(id)
+    }
     expect(getSlackV2ToolAccess()).toEqual(expect.arrayContaining(AGENT_TOOL_IDS))
-    expect(getSlackV2ToolAccess()).not.toEqual(
-      expect.arrayContaining(['slack_set_status', 'slack_set_title', 'slack_set_suggested_prompts'])
-    )
+    expect(getSlackV2ToolAccess()).toContain('slack_set_suggested_prompts')
+    for (const id of ['slack_set_status', 'slack_set_title']) {
+      expect(getSlackV2ToolAccess()).not.toContain(id)
+    }
     expect(Object.keys(getSlackV2OperationSentences())).toEqual(
       expect.arrayContaining(AGENT_OPERATION_IDS)
     )
@@ -70,22 +73,54 @@ describe('Slack block release', () => {
     })
   })
 
-  it('preserves persisted suggested-prompt inputs while requiring the custom-bot tool', () => {
+  it('keeps persisted OAuth suggested prompts on the compatibility tool', () => {
+    const selectTool = SlackV2Block.tools.config?.tool
+    if (!selectTool) throw new Error('Slack v2 tool selector is required')
+
+    expect(
+      selectTool({ operation: 'set_suggested_prompts', oauthCredential: 'oauth-credential' })
+    ).toBe('slack_set_suggested_prompts')
     expect(
       mapSlackV2Params({
         operation: 'set_suggested_prompts',
-        oauthCredential: 'custom-bot-credential',
+        oauthCredential: 'oauth-credential',
         channel: 'C123',
         getThreadTimestamp: '1700000000.000001',
         suggestedPrompts: '[{"title":"Summarize","message":"Summarize this thread"}]',
         promptsTitle: 'Try asking',
       })
     ).toMatchObject({
-      credential: 'custom-bot-credential',
+      credential: 'oauth-credential',
       channel: 'C123',
       threadTs: '1700000000.000001',
       prompts: '[{"title":"Summarize","message":"Summarize this thread"}]',
       promptsTitle: 'Try asking',
     })
   })
+
+  it('uses the service-account tool and active content mode for new agent operations', () => {
+    const selectTool = SlackV2Block.tools.config?.tool
+    if (!selectTool) throw new Error('Slack v2 tool selector is required')
+
+    expect(
+      selectTool({ operation: 'set_suggested_prompts', agentCredentialId: 'custom-bot' })
+    ).toBe('slack_set_suggested_prompts_v2')
+
+    const mapped = mapSlackV2Params({
+      operation: 'append_stream',
+      agentCredentialId: 'custom-bot',
+      agentChannelId: 'C123',
+      streamTs: '1700000000.000001',
+      streamContentMode: 'markdown',
+      streamMarkdownText: 'Current content',
+      streamChunks: [{ type: 'markdown_text', text: 'Stale content' }],
+    })
+    expect(mapped).toMatchObject({
+      credential: 'custom-bot',
+      channel: 'C123',
+      ts: '1700000000.000001',
+      markdownText: 'Current content',
+    })
+    expect(mapped.chunks).toBeUndefined()
+  })
 })

apps/sim/blocks/blocks/slack.ts

@@ -3447,6 +3447,7 @@ export const SlackV2Block: BlockConfig<SlackResponse> = {
       'slack_get_thread_replies',
       'slack_get_channel_history',
       'slack_get_permalink',
+      'slack_set_suggested_prompts',
       'slack_set_suggested_prompts_v2',
       'slack_set_agent_session_status_v2',
       'slack_rename_agent_session_v2',
@@ -3488,7 +3489,9 @@ export const SlackV2Block: BlockConfig<SlackResponse> = {
       tool: (params) => {
         switch (params.operation) {
           case 'set_suggested_prompts':
-            return 'slack_set_suggested_prompts_v2'
+            return params.agentCredentialId
+              ? 'slack_set_suggested_prompts_v2'
+              : 'slack_set_suggested_prompts'
           case 'set_agent_session_status':
             return 'slack_set_agent_session_status_v2'
           case 'rename_agent_session':
@@ -3511,26 +3514,21 @@ export const SlackV2Block: BlockConfig<SlackResponse> = {
         if (!mapParams) throw new Error('Slack parameter mapper is required')
         const baseParams = mapParams(params)
         if (!SLACK_V2_AGENT_OPERATIONS.includes(params.operation as never)) return baseParams
-
-        const persistedSuggestedPromptParams =
-          params.operation === 'set_suggested_prompts'
-            ? {
-                credential: baseParams.credential,
-                channel: baseParams.channel,
-                threadTs: baseParams.threadTs,
-              }
-            : undefined
+        if (params.operation === 'set_suggested_prompts' && !params.agentCredentialId) {
+          return baseParams
+        }
 
         return {
           ...baseParams,
-          credential: params.agentCredentialId ?? persistedSuggestedPromptParams?.credential,
-          channel: params.agentChannelId ?? persistedSuggestedPromptParams?.channel,
-          threadTs: params.agentThreadTs ?? persistedSuggestedPromptParams?.threadTs,
+          credential: params.agentCredentialId,
+          channel: params.agentChannelId,
+          threadTs: params.agentThreadTs,
           status: params.agentSessionStatus,
           title: params.agentSessionTitle,
           initiatorUserId: params.agentInitiatorUserId,
-          markdownText: params.streamMarkdownText,
-          chunks: params.streamChunks,
+          markdownText:
+            params.streamContentMode === 'markdown' ? params.streamMarkdownText : undefined,
+          chunks: params.streamContentMode === 'chunks' ? params.streamChunks : undefined,
           ts: params.streamTs,
           recipientUserId: params.streamRecipientUserId,
           recipientTeamId: params.streamRecipientTeamId,

apps/sim/lib/oauth/utils.ts

@@ -314,7 +314,7 @@ export const SCOPE_DESCRIPTIONS: Record<string, string> = {
   'chat:write': 'Send messages',
   'chat:write.public': 'Post to public channels',
   'chat:write.customize': 'Customize message username and icon',
-  'assistant:write': 'Set suggested prompts for Agent View',
+  'assistant:write': 'Manage assistant status, titles, and suggested prompts',
   'im:write': 'Send direct messages',
   'im:history': 'Read direct message history',
   'im:read': 'View direct message channels',

apps/sim/tools/generated/tool-metadata.ts

@@ -4479,6 +4479,8 @@ describe('Copilot OAuth Credential Enforcement', () => {
       credential: 'custom-slack-bot',
       channel: 'C1',
       markdownText: 'hello',
+      recipientUserId: 'U1',
+      recipientTeamId: 'T1',
     })
 
     expect(result).toMatchObject({

apps/sim/tools/generated/tool-outputs.ts

@@ -28,11 +28,14 @@ describe('Slack Agent Sessions tools', () => {
     for (const tool of AGENT_TOOLS) {
       expect(tool.oauth).toMatchObject({
         provider: 'slack',
-        requiredScopes: ['chat:write'],
         credentialKind: 'service-account',
       })
+      expect(tool.oauth?.requiredScopes).toContain('chat:write')
       expect(requestOf(tool).url({})).toMatch(/^https:\/\/slack\.com\/api\//)
     }
+    for (const tool of [slackSetAgentSessionStatusV2Tool, slackStartStreamV2Tool]) {
+      expect(tool.oauth?.requiredScopes).toContain('chat:write.customize')
+    }
   })
 
   it('maps the documented session status request and response', async () => {
@@ -147,6 +150,24 @@ describe('Slack streaming tools', () => {
     })
   })
 
+  it('requires recipient IDs for channel streams but not direct messages', () => {
+    const request = requestOf(slackStartStreamV2Tool)
+    const base = {
+      accessToken: 'xoxb-token',
+      authMethod: 'bot_token',
+      botToken: '',
+      markdownText: 'First',
+    }
+
+    expect(() => request.body?.({ ...base, channel: 'C1' })).toThrow(
+      'Recipient User ID and Recipient Team ID are required for channel streams'
+    )
+    expect(request.body?.({ ...base, channel: 'D1' })).toEqual({
+      channel: 'D1',
+      markdown_text: 'First',
+    })
+  })
+
   it('rejects mixed streaming content modes and empty appends', () => {
     const append = requestOf(slackAppendStreamV2Tool)
     const base = {

apps/sim/tools/index.test.ts

@@ -61,13 +61,14 @@ export const slackAppendStreamV2Tool: ToolConfig<SlackAppendStreamV2Params, Slac
         type: 'string',
         required: false,
         visibility: 'user-or-llm',
-        description: 'Markdown content to append, mutually exclusive with chunks',
+        description: 'Markdown content to append; provide this or chunks, but not both',
       },
       chunks: {
         type: 'json',
         required: false,
         visibility: 'user-or-llm',
-        description: 'Structured Slack streaming chunks, mutually exclusive with Markdown',
+        description:
+          'Structured Slack streaming chunks; provide this or Markdown Text, but not both',
       },
     },
     request: {