feat(custom-blocks): add deploy_custom_block copilot tool

apps/sim/app/api/mothership/execute/route.ts

@@ -8,6 +8,7 @@ import { checkInternalAuth } from '@/lib/auth/hybrid'
 import { buildIntegrationToolSchemas } from '@/lib/copilot/chat/payload'
 import { processContextsServer } from '@/lib/copilot/chat/process-contents'
 import { generateWorkspaceContext } from '@/lib/copilot/chat/workspace-context'
+import { computeWorkspaceEntitlements } from '@/lib/copilot/entitlements'
 import {
   MothershipStreamV1EventType,
   MothershipStreamV1TextChannel,
@@ -141,25 +142,32 @@ export const POST = withRouteHandler(async (req: NextRequest) => {
     const lastUserMessage = messages.filter((m) => m.role === 'user').at(-1)?.content
     // double-cast-allowed: the contract validates contexts as open kind/label objects; processContextsServer narrows on `kind` at runtime
     const agentMentions = contexts as unknown as ChatContext[] | undefined
-    const [workspaceContext, integrationTools, userSkillTool, userPermission, agentContexts] =
-      await Promise.all([
-        generateWorkspaceContext(workspaceId, userId),
-        buildIntegrationToolSchemas(userId, messageId, undefined, workspaceId),
-        buildUserSkillTool(workspaceId),
-        getUserEntityPermissions(userId, 'workspace', workspaceId).catch(() => null),
-        processContextsServer(
-          agentMentions,
-          userId,
-          lastUserMessage,
-          workspaceId,
-          effectiveChatId
-        ).catch((error) => {
-          reqLogger.warn('Failed to resolve agent contexts for execution', {
-            error: toError(error).message,
-          })
-          return []
-        }),
-      ])
+    const [
+      workspaceContext,
+      integrationTools,
+      userSkillTool,
+      userPermission,
+      entitlements,
+      agentContexts,
+    ] = await Promise.all([
+      generateWorkspaceContext(workspaceId, userId),
+      buildIntegrationToolSchemas(userId, messageId, undefined, workspaceId),
+      buildUserSkillTool(workspaceId),
+      getUserEntityPermissions(userId, 'workspace', workspaceId).catch(() => null),
+      computeWorkspaceEntitlements(workspaceId, userId),
+      processContextsServer(
+        agentMentions,
+        userId,
+        lastUserMessage,
+        workspaceId,
+        effectiveChatId
+      ).catch((error) => {
+        reqLogger.warn('Failed to resolve agent contexts for execution', {
+          error: toError(error).message,
+        })
+        return []
+      }),
+    ])
     const requestPayload: Record<string, unknown> = {
       messages,
       responseFormat,
@@ -182,6 +190,7 @@ export const POST = withRouteHandler(async (req: NextRequest) => {
       ...(integrationTools.length > 0 ? { integrationTools } : {}),
       ...(userSkillTool ? { mothershipTools: [userSkillTool] } : {}),
       ...(userPermission ? { userPermission } : {}),
+      ...(entitlements.length > 0 ? { entitlements } : {}),
     }
 
     let allowExplicitAbort = true

apps/sim/lib/copilot/chat/payload.test.ts

@@ -237,4 +237,34 @@ describe('buildCopilotRequestPayload', () => {
       })
     )
   })
+
+  it('passes entitlements through and omits the field when empty', async () => {
+    const withEntitlements = await buildCopilotRequestPayload(
+      {
+        message: 'publish as a block',
+        userId: 'user-1',
+        userMessageId: 'msg-1',
+        mode: 'agent',
+        model: 'claude-opus-4-8',
+        workspaceId: 'ws-1',
+        entitlements: ['custom-blocks'],
+      },
+      { selectedModel: 'claude-opus-4-8' }
+    )
+    expect(withEntitlements).toEqual(expect.objectContaining({ entitlements: ['custom-blocks'] }))
+
+    const withoutEntitlements = await buildCopilotRequestPayload(
+      {
+        message: 'publish as a block',
+        userId: 'user-1',
+        userMessageId: 'msg-1',
+        mode: 'agent',
+        model: 'claude-opus-4-8',
+        workspaceId: 'ws-1',
+        entitlements: [],
+      },
+      { selectedModel: 'claude-opus-4-8' }
+    )
+    expect(withoutEntitlements).not.toHaveProperty('entitlements')
+  })
 })

apps/sim/lib/copilot/chat/payload.ts

@@ -41,6 +41,8 @@ interface BuildPayloadParams {
   workspaceContext?: string
   vfs?: VfsSnapshotV1
   userPermission?: string
+  /** Plan/flag-gated org capabilities (e.g. "custom-blocks") the mothership gates tools/prompts on. */
+  entitlements?: string[]
   userTimezone?: string
   userMetadata?: {
     name?: string
@@ -387,6 +389,7 @@ export async function buildCopilotRequestPayload(
     ...(params.workspaceContext ? { workspaceContext: params.workspaceContext } : {}),
     ...(params.vfs ? { vfs: params.vfs } : {}),
     ...(params.userPermission ? { userPermission: params.userPermission } : {}),
+    ...(params.entitlements?.length ? { entitlements: params.entitlements } : {}),
     ...(params.userTimezone ? { userTimezone: params.userTimezone } : {}),
     ...(params.userMetadata &&
     (params.userMetadata.name || params.userMetadata.email || params.userMetadata.timezone)

apps/sim/lib/copilot/chat/post.ts

@@ -25,6 +25,7 @@ import { finalizeAssistantTurn } from '@/lib/copilot/chat/terminal-state'
 import { generateWorkspaceSnapshot } from '@/lib/copilot/chat/workspace-context'
 import { chatPubSub } from '@/lib/copilot/chat-status'
 import { COPILOT_REQUEST_MODES } from '@/lib/copilot/constants'
+import { computeWorkspaceEntitlements } from '@/lib/copilot/entitlements'
 import {
   CopilotChatFinalizeOutcome,
   CopilotChatPersistOutcome,
@@ -175,6 +176,7 @@ type UnifiedChatBranch =
         contexts: Array<{ type: string; content: string; tag?: string; path?: string }>
         fileAttachments?: UnifiedChatRequest['fileAttachments']
         userPermission?: string
+        entitlements?: string[]
         userTimezone?: string
         userMetadata?: { name?: string; email?: string; timezone?: string }
         workflowId: string
@@ -212,6 +214,7 @@ type UnifiedChatBranch =
         contexts: Array<{ type: string; content: string; tag?: string; path?: string }>
         fileAttachments?: UnifiedChatRequest['fileAttachments']
         userPermission?: string
+        entitlements?: string[]
         userTimezone?: string
         userMetadata?: { name?: string; email?: string; timezone?: string }
         workspaceContext?: string
@@ -624,6 +627,7 @@ async function resolveBranch(params: {
             workspaceContext: payloadParams.workspaceContext,
             vfs: payloadParams.vfs,
             userPermission: payloadParams.userPermission,
+            entitlements: payloadParams.entitlements,
             userTimezone: payloadParams.userTimezone,
             userMetadata: payloadParams.userMetadata,
           },
@@ -679,6 +683,7 @@ async function resolveBranch(params: {
           workspaceContext: payloadParams.workspaceContext,
           vfs: payloadParams.vfs,
           userPermission: payloadParams.userPermission,
+          entitlements: payloadParams.entitlements,
           userTimezone: payloadParams.userTimezone,
           userMetadata: payloadParams.userMetadata,
           includeMothershipTools: true,
@@ -899,6 +904,9 @@ export async function handleUnifiedChatPost(req: NextRequest) {
                 }
               )
             : Promise.resolve(null)
+      const entitlementsPromise = workspaceId
+        ? computeWorkspaceEntitlements(workspaceId, authenticatedUserId)
+        : Promise.resolve([])
       // Wrap the pre-LLM prep work in spans so the trace waterfall shows
       // where time is going between "request received" and "llm.stream
       // opens". Previously these ran bare under the root and inflated the
@@ -953,10 +961,11 @@ export async function handleUnifiedChatPost(req: NextRequest) {
         activeOtelRoot.context
       )
 
-      const [agentContexts, userPermission, workspaceSnapshot, , executionContext] =
+      const [agentContexts, userPermission, entitlements, workspaceSnapshot, , executionContext] =
         await Promise.all([
           agentContextsPromise,
           userPermissionPromise,
+          entitlementsPromise,
           workspaceContextPromise,
           persistUserMessagePromise,
           executionContextPromise,
@@ -991,6 +1000,7 @@ export async function handleUnifiedChatPost(req: NextRequest) {
                 contexts: agentContexts,
                 fileAttachments: body.fileAttachments,
                 userPermission: userPermission ?? undefined,
+                entitlements,
                 userTimezone: body.userTimezone,
                 userMetadata,
                 workflowId: branch.workflowId,
@@ -1012,6 +1022,7 @@ export async function handleUnifiedChatPost(req: NextRequest) {
                 contexts: agentContexts,
                 fileAttachments: body.fileAttachments,
                 userPermission: userPermission ?? undefined,
+                entitlements,
                 userTimezone: body.userTimezone,
                 userMetadata,
                 workspaceContext,

apps/sim/lib/copilot/entitlements.ts

@@ -0,0 +1,72 @@
+import { createLogger } from '@sim/logger'
+import { getErrorMessage } from '@sim/utils/errors'
+import { LRUCache } from 'lru-cache'
+import { isCustomBlocksEligible } from '@/lib/workflows/custom-blocks/operations'
+
+const logger = createLogger('CopilotEntitlements')
+
+/**
+ * Cross-repo contract: the mothership (Go) matches these exact strings against
+ * its `core.Entitlement*` constants to gate agent surfaces.
+ */
+export const CUSTOM_BLOCKS_ENTITLEMENT = 'custom-blocks'
+
+/**
+ * Workspace entitlements — plan/flag-gated org capabilities sent to the
+ * mothership as the chat payload's `entitlements` array. The Go side hides the
+ * matching tools, skills, and prompt sections when an entitlement is absent, so
+ * a non-entitled org's agents never hear of the feature.
+ *
+ * Adding an entitlement:
+ * 1. Add the kebab-case name and a fail-closed evaluator here. Every payload
+ *    site (interactive chat, headless execute, inbox) picks it up automatically.
+ * 2. Go repo: add the matching `Entitlement*` constant in `internal/core` and
+ *    gate surfaces declaratively — `RequiredEntitlement` on tool definitions,
+ *    `entitlement:` frontmatter on skills, a conditional section in
+ *    `BuildAgentEnvelope`, or a variant swap in `Capabilities`.
+ * 3. Keep enforcement in sim: the Go gating is advertisement-only (the payload
+ *    is forgeable), so the sim-side tool handler must re-check the same
+ *    predicate at execution time.
+ */
+const ENTITLEMENT_EVALUATORS: Record<
+  string,
+  (workspaceId: string, userId?: string) => Promise<boolean>
+> = {
+  [CUSTOM_BLOCKS_ENTITLEMENT]: isCustomBlocksEligible,
+}
+
+const entitlementsCache = new LRUCache<string, Promise<string[]>>({
+  max: 500,
+  ttl: 5_000,
+})
+
+/**
+ * The entitlements to send to the mothership for a request in this workspace.
+ * Each evaluator fails closed (an error means the entitlement is absent).
+ * Cached briefly so the several per-message callers collapse to one evaluation.
+ */
+export function computeWorkspaceEntitlements(
+  workspaceId: string,
+  userId?: string
+): Promise<string[]> {
+  const cacheKey = `${workspaceId}:${userId ?? ''}`
+  const cached = entitlementsCache.get(cacheKey)
+  if (cached) return cached
+
+  const promise = Promise.all(
+    Object.entries(ENTITLEMENT_EVALUATORS).map(async ([name, evaluate]) => {
+      try {
+        return (await evaluate(workspaceId, userId)) ? name : null
+      } catch (error) {
+        logger.warn('Entitlement evaluation failed; treating as absent', {
+          entitlement: name,
+          workspaceId,
+          error: getErrorMessage(error),
+        })
+        return null
+      }
+    })
+  ).then((names) => names.filter((name): name is string => name !== null))
+  entitlementsCache.set(cacheKey, promise)
+  return promise
+}