fix(entitlements): gate paid MCP tools (send_invoice/agi_submit/vat_declaration_submit) server-side (#846)

The HTTP routes call requireCapability at every paid chokepoint, but the
MCP/agent path bypassed the paywall entirely: the three external-service
tools stage operations whose commit calls the email / Skatteverket services
directly, with no capability check. After the 2026-07-07 trial cutover a
trial-connected non-payer using the gnubok MCP connector could still send
invoice emails and file AGI/VAT.

Close the gap with two layers, mirroring the existing TOOL_SCOPE_MAP gate:

- Dispatch gate (mcp-server/server.ts): MCP_TOOL_CAPABILITY_MAP, checked
  right after the scope check, blocks a non-entitled company before any
  pending op is staged. Emits errorKind='capability_denied' telemetry.
- Commit-time gate (commitPendingOperation): PAID_OPERATION_CAPABILITY_MAP,
  checked before the atomic claim. The real external-service chokepoint —
  applies to the MCP approve tool AND the UI approval path, and closes the
  trial-connected-token window (the grant has expired by commit time). A
  blocked op stays 'pending', so it is re-approvable once the company subscribes.

Adds a transport-free capabilityBlockedError() helper (shared bilingual
copy) and locks both maps with tests (maps, dispatch gate, commit gate).
Only the three write/submit tools are gated; SKV read/local tools stay free
per the statutory carve-out. No DB/migration change; self-hosted stays all-on.

Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

lib/entitlements/__tests__/capability-maps.test.ts

@@ -0,0 +1,51 @@
+import { describe, it, expect } from 'vitest'
+import {
+  MCP_TOOL_CAPABILITY_MAP,
+  PAID_OPERATION_CAPABILITY_MAP,
+  PAID_CAPABILITIES,
+  CAPABILITY,
+} from '../keys'
+
+/**
+ * These maps are the contract that gates the paid MCP/agent path (dispatch +
+ * commit). Locking the exact entries is the guard against a future paid
+ * external-service tool silently bypassing the paywall — mirrors the
+ * TOOL_SCOPE_MAP assertions in the mcp-server tests.
+ */
+describe('MCP_TOOL_CAPABILITY_MAP', () => {
+  it('gates exactly the three paid external-service MCP tools', () => {
+    expect(MCP_TOOL_CAPABILITY_MAP).toEqual({
+      gnubok_send_invoice: CAPABILITY.email_send,
+      gnubok_vat_declaration_submit: CAPABILITY.skatteverket,
+      gnubok_agi_submit: CAPABILITY.skatteverket,
+    })
+  })
+
+  it('only maps tools to PAID capabilities', () => {
+    for (const key of Object.values(MCP_TOOL_CAPABILITY_MAP)) {
+      expect(PAID_CAPABILITIES).toContain(key)
+    }
+  })
+})
+
+describe('PAID_OPERATION_CAPABILITY_MAP', () => {
+  it('gates exactly the three paid pending-operation types', () => {
+    expect(PAID_OPERATION_CAPABILITY_MAP).toEqual({
+      send_invoice: CAPABILITY.email_send,
+      submit_vat_declaration: CAPABILITY.skatteverket,
+      submit_agi: CAPABILITY.skatteverket,
+    })
+  })
+
+  it('only maps operations to PAID capabilities', () => {
+    for (const key of Object.values(PAID_OPERATION_CAPABILITY_MAP)) {
+      expect(PAID_CAPABILITIES).toContain(key)
+    }
+  })
+
+  it('covers the same set of capabilities as the MCP tool map (dispatch ↔ commit parity)', () => {
+    expect(new Set(Object.values(PAID_OPERATION_CAPABILITY_MAP))).toEqual(
+      new Set(Object.values(MCP_TOOL_CAPABILITY_MAP)),
+    )
+  })
+})

lib/entitlements/has-capability.ts

@@ -80,6 +80,12 @@ export async function hasCapability(
   return true
 }
 
+/** Bilingual paywall copy, shared by every transport (HTTP route, MCP tool, commit executor). */
+export const CAPABILITY_BLOCKED_MESSAGE_SV =
+  'Den här funktionen kräver en betald prenumeration. Uppgradera för att fortsätta använda externa tjänster.'
+export const CAPABILITY_BLOCKED_MESSAGE_EN =
+  'This feature requires a paid subscription. Upgrade to keep using external services.'
+
 /**
  * Standard bilingual 403 for a capability-blocked endpoint. Matches the
  * sandbox/guard envelope so the UI surfaces the upsell consistently.
@@ -87,10 +93,8 @@ export async function hasCapability(
 export function capabilityBlockedResponse(key: CapabilityKey): NextResponse {
   return NextResponse.json(
     {
-      error:
-        'Den här funktionen kräver en betald prenumeration. Uppgradera för att fortsätta använda externa tjänster.',
-      error_en:
-        'This feature requires a paid subscription. Upgrade to keep using external services.',
+      error: CAPABILITY_BLOCKED_MESSAGE_SV,
+      error_en: CAPABILITY_BLOCKED_MESSAGE_EN,
       capability_blocked: true,
       capability: key,
     },
@@ -98,6 +102,30 @@ export function capabilityBlockedResponse(key: CapabilityKey): NextResponse {
   )
 }
 
+export interface CapabilityBlockedError {
+  code: 'capability_blocked'
+  capability_blocked: true
+  capability: CapabilityKey
+  message_sv: string
+  message_en: string
+}
+
+/**
+ * Transport-free counterpart to capabilityBlockedResponse, for call sites that
+ * don't return a NextResponse — the MCP dispatcher (folded into the JSON-RPC
+ * `isError` envelope) and the pending-operation commit executor. Same copy and
+ * the same `capability_blocked: true` marker so every surface upsells alike.
+ */
+export function capabilityBlockedError(key: CapabilityKey): CapabilityBlockedError {
+  return {
+    code: 'capability_blocked',
+    capability_blocked: true,
+    capability: key,
+    message_sv: CAPABILITY_BLOCKED_MESSAGE_SV,
+    message_en: CAPABILITY_BLOCKED_MESSAGE_EN,
+  }
+}
+
 /**
  * Convenience wrapper: check + return the 403 in one call. Returns the
  * NextResponse to return from the route, or null when the company has the

lib/entitlements/keys.ts

@@ -53,3 +53,34 @@ export const PAID_CAPABILITIES: readonly CapabilityKey[] = [
   CAPABILITY.skatteverket,
   CAPABILITY.email_send,
 ] as const
+
+/**
+ * Paid MCP tools → required capability. The MCP/agent path is a paid chokepoint
+ * just like the HTTP routes, so the dispatcher gates these the same way it gates
+ * API-key scope (see mcp-server `tools/call`). Only external-service WRITE tools
+ * appear here: send_invoice (email) and the two Skatteverket submissions. The
+ * read/local SKV tools (generate_agi, vat_declaration_validate/status, agi_status)
+ * stay free — the §4 carve-out forbids blocking a statutory filing obligation.
+ *
+ * No MCP tool invokes AI or triggers bank sync, so those PAID capabilities have
+ * no entry here — they are reachable only via already-gated HTTP routes/handlers.
+ */
+export const MCP_TOOL_CAPABILITY_MAP: Readonly<Partial<Record<string, CapabilityKey>>> = {
+  gnubok_send_invoice: CAPABILITY.email_send,
+  gnubok_vat_declaration_submit: CAPABILITY.skatteverket,
+  gnubok_agi_submit: CAPABILITY.skatteverket,
+} as const
+
+/**
+ * Paid pending-operation types → required capability. Keyed by
+ * `pending_operations.operation_type`. This is the commit-time twin of
+ * MCP_TOOL_CAPABILITY_MAP: it gates the actual external-service call inside
+ * commitPendingOperation, so an operation staged during the trial cannot be
+ * committed once the grant has expired — regardless of caller (MCP approve tool
+ * or the UI approval path). Keep the values in sync with MCP_TOOL_CAPABILITY_MAP.
+ */
+export const PAID_OPERATION_CAPABILITY_MAP: Readonly<Partial<Record<string, CapabilityKey>>> = {
+  send_invoice: CAPABILITY.email_send,
+  submit_vat_declaration: CAPABILITY.skatteverket,
+  submit_agi: CAPABILITY.skatteverket,
+} as const

lib/events/types.ts

@@ -168,7 +168,7 @@ export type CoreEvent =
       success: boolean                              // true iff the tool returned without throwing AND was invoked (not denied)
       isError: boolean                              // matches the JSON-RPC tool-result isError flag returned to the client
       errorCode: string | null                      // structured error code from tool-result.toToolError when applicable
-      errorKind: 'execution' | 'scope_denied' | 'unknown_tool' | null
+      errorKind: 'execution' | 'scope_denied' | 'capability_denied' | 'unknown_tool' | null
       errorMessage: string | null                   // human-readable error message (truncated to 500 chars), null on success.
                                                     // Raw material for clustering real agent failures into curated gotchas —
                                                     // errorCode alone can't distinguish "period locked" from "unbalanced".

lib/pending-operations/__tests__/commit-capability-gate.test.ts

@@ -0,0 +1,91 @@
+/**
+ * Tests for the commit-time capability gate in commitPendingOperation.
+ *
+ * This is the twin of the MCP dispatch gate and the true external-service
+ * chokepoint: it runs BEFORE the atomic claim, so a blocked op stays 'pending'
+ * (re-approvable once the company subscribes) and an op staged DURING the trial
+ * cannot be committed once the grant expires — regardless of caller (MCP approve
+ * tool or the UI approval path).
+ */
+import { describe, it, expect, vi, beforeEach } from 'vitest'
+import { eventBus } from '@/lib/events/bus'
+import { createQueuedMockSupabase } from '@/tests/helpers'
+import type { PendingOperation } from '@/types'
+
+vi.mock('@/lib/entitlements/has-capability', async (importOriginal) => {
+  const actual = await importOriginal<typeof import('@/lib/entitlements/has-capability')>()
+  return { ...actual, hasCapability: vi.fn() }
+})
+
+import { commitPendingOperation } from '../commit'
+import { hasCapability } from '@/lib/entitlements/has-capability'
+
+const mockHasCapability = vi.mocked(hasCapability)
+
+function makePendingOp(overrides: Partial<PendingOperation>): PendingOperation {
+  return {
+    id: 'op-1',
+    user_id: 'user-1',
+    company_id: 'company-1',
+    operation_type: 'send_invoice',
+    status: 'pending',
+    title: 'test',
+    params: {},
+    preview_data: {},
+    result_data: null,
+    actor_type: 'user',
+    actor_id: null,
+    actor_label: null,
+    risk_level: 'high',
+    created_at: '2026-06-01T00:00:00Z',
+    resolved_at: null,
+    updated_at: '2026-06-01T00:00:00Z',
+    ...overrides,
+  } as PendingOperation
+}
+
+beforeEach(() => {
+  vi.clearAllMocks()
+  eventBus.clear()
+})
+
+describe('commitPendingOperation: capability gate', () => {
+  it('blocks send_invoice when email_send is not entitled — 403, op left pending', async () => {
+    mockHasCapability.mockResolvedValue(false)
+    const { supabase } = createQueuedMockSupabase() // no responses enqueued: the claim must never run
+
+    const op = makePendingOp({ operation_type: 'send_invoice', params: { invoice_id: 'inv-1' } })
+    const result = await commitPendingOperation(supabase as never, 'user-1', 'company-1', op)
+
+    expect(result.status).toBe('failed')
+    expect(result.http_status).toBe(403)
+    expect(result.code).toBe('capability_blocked')
+    expect(mockHasCapability).toHaveBeenCalledWith(supabase, 'company-1', 'email_send')
+  })
+
+  it('blocks submit_vat_declaration when skatteverket is not entitled', async () => {
+    mockHasCapability.mockResolvedValue(false)
+    const { supabase } = createQueuedMockSupabase()
+
+    const op = makePendingOp({ operation_type: 'submit_vat_declaration', params: { period_type: 'monthly', year: 2025, period: 3 } })
+    const result = await commitPendingOperation(supabase as never, 'user-1', 'company-1', op)
+
+    expect(result.status).toBe('failed')
+    expect(result.http_status).toBe(403)
+    expect(result.code).toBe('capability_blocked')
+    expect(mockHasCapability).toHaveBeenCalledWith(supabase, 'company-1', 'skatteverket')
+  })
+
+  it('does NOT consult the gate for a free operation type', async () => {
+    mockHasCapability.mockResolvedValue(false)
+    const { supabase, enqueue } = createQueuedMockSupabase()
+    enqueue({ data: null, error: null }) // claim resolves to "already claimed" → early 409, before any executor
+
+    const op = makePendingOp({ operation_type: 'create_customer', params: { name: 'x' } })
+    const result = await commitPendingOperation(supabase as never, 'user-1', 'company-1', op)
+
+    // create_customer is not in PAID_OPERATION_CAPABILITY_MAP — the gate is skipped.
+    expect(mockHasCapability).not.toHaveBeenCalled()
+    expect(result.status).toBe('failed') // claim returned no row (409); proves we got past the gate
+  })
+})

lib/pending-operations/__tests__/skatteverket-executors.test.ts

@@ -21,6 +21,15 @@ import type { SkvSubmitResult } from '@/lib/pending-operations/skatteverket-comm
 import type { PendingOperation } from '@/types'
 import { commitPendingOperation } from '../commit'
 
+// The commit-time capability gate (PR: gate paid MCP tools) runs hasCapability
+// before the atomic claim for submit_vat_declaration/submit_agi. These tests
+// isolate the registry/lifecycle wiring, so make the gate transparent here;
+// its enforcement is covered by commit-capability-gate.test.ts.
+vi.mock('@/lib/entitlements/has-capability', async (importOriginal) => {
+  const actual = await importOriginal<typeof import('@/lib/entitlements/has-capability')>()
+  return { ...actual, hasCapability: vi.fn().mockResolvedValue(true) }
+})
+
 function makePendingOp(overrides: Partial<PendingOperation>): PendingOperation {
   return {
     id: 'op-1',

lib/pending-operations/commit.ts

@@ -60,6 +60,8 @@ import {
   type SkvSubmitResult,
 } from '@/lib/pending-operations/skatteverket-commit'
 import { getEmailService } from '@/lib/email/service'
+import { hasCapability, CAPABILITY_BLOCKED_MESSAGE_SV } from '@/lib/entitlements/has-capability'
+import { PAID_OPERATION_CAPABILITY_MAP } from '@/lib/entitlements/keys'
 import {
   generateInvoiceEmailHtml,
   generateInvoiceEmailText,
@@ -3665,6 +3667,23 @@ async function commitPendingOperationInner(
   pendingOp: PendingOperation,
   opts: CommitOptions = {}
 ): Promise<CommitResult> {
+  // ── Capability gate (commit-time twin of the MCP dispatch gate). The actual
+  //    external-service call (email / Skatteverket submit) happens below, so
+  //    this is the true paid chokepoint — it also catches an op STAGED during
+  //    the trial then approved AFTER the grant expired, regardless of caller
+  //    (MCP approve tool or the UI approval path). Checked BEFORE the atomic
+  //    claim so a blocked op stays 'pending' and is re-approvable once the
+  //    company subscribes. Self-hosted short-circuits to all-on in hasCapability.
+  const requiredCapability = PAID_OPERATION_CAPABILITY_MAP[pendingOp.operation_type]
+  if (requiredCapability && !(await hasCapability(supabase, companyId, requiredCapability))) {
+    return {
+      status: 'failed',
+      error: CAPABILITY_BLOCKED_MESSAGE_SV,
+      http_status: 403,
+      code: 'capability_blocked',
+    }
+  }
+
   // ── Atomic claim: flip status pending → committing in a single conditional
   //    update. If 0 rows are affected, another caller (auto-commit ↔ human
   //    approval, or two parallel approvals) already claimed this op and we