fix(agent): the assistant reaches earlier räkenskapsår: period resolved from dates, years listed in the grounding (#2436)

Part 3 of #2185. A user with several imported years concluded the assistant
"only reads the period I am standing in". Nothing restricted it: the report
tools defaulted to the most recent fiscal period when no period_id was given
and then rejected any from_date/to_date/as_of_date outside it, and neither
the snapshot nor the chat identity block told the model which years existed
or how to address them.

- extensions/general/mcp-server/server.ts: resolveReportPeriod takes a date
  hint; without period_id, a date in the call resolves the fiscal period that
  contains it (findFiscalPeriodContaining, company-scoped), and a date no
  period covers fails with the company's span instead of the latest year's
  bounds. Income statement (from_date or to_date), balance sheet (as_of_date)
  and dimension P&L (to_date) use it. The range guard is unchanged. No schema
  change: tools/list sits at its token ceiling.
- lib/agent/fiscal-years.ts: one query and one line, "Räkenskapsår (senaste
  först): ... period_id=<uuid> (senaste|avslutat)", plus the rule on
  addressing an earlier year, shared by the single-call snapshot and the
  streaming chat's always-on identity block.
- lib/agent/intents/shared-rules.ts and TOOL_RULES: pass that year's
  period_id, one call per year, and say which räkenskapsår the answer covers.


Claude-Session: https://claude.ai/code/session_0179bdetHyofL6ATfQxB5wP5

Co-authored-by: Jakob Wennberg <311770904+jakobwennberg-oss@users.noreply.github.com>
Co-authored-by: Claude Fable 5.1 <noreply@anthropic.com>

lib/agent/chat/__tests__/system-prompt.test.ts

@@ -28,7 +28,9 @@ const intent: AgentIntent = {
   promptTemplate: () => '',
 }
 
-function block(vatStatus: VatStatus): string {
+type FiscalYears = Parameters<typeof buildIdentityBlock>[0]['fiscalYears']
+
+function block(vatStatus: VatStatus, fiscalYears?: FiscalYears): string {
   return buildIdentityBlock({
     intent,
     companyId: 'c1',
@@ -38,6 +40,7 @@ function block(vatStatus: VatStatus): string {
     rankedMemory: [],
     vatStatus,
     today: '2026-01-01 (torsdag)',
+    fiscalYears,
     // buildIdentityBlock never touches supabase; it's a pure render of args.
     supabase: {} as unknown as SupabaseClient,
   })
@@ -109,3 +112,26 @@ describe('chat system prompt: always-on epistemics rules', () => {
     expect(out).toContain('redan laddad')
   })
 })
+
+// #2185: a multi-year ledger read as single-year to the model because the
+// report tools default to the most recent period and nothing told it other
+// years existed. The inventory and the rule are always-on (Block 2), since
+// the question about an earlier year tends to come many turns in.
+describe('chat system prompt: räkenskapsår inventory', () => {
+  it('lists the years with their period_id and the rule for addressing them', () => {
+    const out = block(null, [
+      { id: 'fp-2026', name: '2026', period_start: '2026-01-01', period_end: '2026-12-31', is_closed: false },
+      { id: 'fp-2024', name: '2024', period_start: '2024-01-01', period_end: '2024-12-31', is_closed: true },
+    ])
+    expect(out).toContain('# Räkenskapsår')
+    expect(out).toContain('2026-01-01..2026-12-31 period_id=fp-2026 (senaste)')
+    expect(out).toContain('2024-01-01..2024-12-31 period_id=fp-2024 (avslutat)')
+    expect(out).toContain('skicka det årets period_id')
+    expect(out).toContain('Säg alltid vilket räkenskapsår svaret gäller')
+  })
+
+  it('renders no section when the company has no periods', () => {
+    expect(block(null, [])).not.toContain('# Räkenskapsår')
+    expect(block(null)).not.toContain('# Räkenskapsår')
+  })
+})

lib/agent/chat/run-turn.ts

@@ -11,6 +11,7 @@ import { agentToolRegistry } from '@/lib/agent/tools/registry'
 import type { AgentTool, AgentActorContext, StagedOperationResult } from '@/lib/agent/tools/types'
 import { isStagedOperation } from '@/lib/agent/tools/types'
 import { buildSystemPrompt } from './system-prompt'
+import { loadFiscalYearInventory } from '@/lib/agent/fiscal-years'
 import { createLogger } from '@/lib/logger'
 import { swedishToday } from '@/lib/utils'
 
@@ -258,12 +259,13 @@ export async function runChatTurn(args: RunTurnArgs): Promise<void> {
   // On a first turn the caller already read the profile summary to build the
   // intent's prompt template, so it hands it over rather than making the same
   // round trip again for the system prompt.
-  const [profile, memory, vatStatus] = await Promise.all([
+  const [profile, memory, vatStatus, fiscalYears] = await Promise.all([
     args.preloadedProfileSummary !== undefined
       ? Promise.resolve(args.preloadedProfileSummary)
       : loadProfileSummary(supabase, companyId),
     loadRankedMemory(supabase, companyId, 30),
     loadVatStatus(supabase, companyId),
+    loadFiscalYearInventory(supabase, companyId),
   ])
 
   const systemPrompt = await buildSystemPrompt({
@@ -275,6 +277,7 @@ export async function runChatTurn(args: RunTurnArgs): Promise<void> {
     rankedMemory: memory,
     vatStatus,
     today: swedishToday(),
+    fiscalYears,
     supabase,
   })
 

lib/agent/chat/system-prompt.ts

@@ -3,6 +3,11 @@ import { join } from 'node:path'
 import type { SupabaseClient } from '@supabase/supabase-js'
 import { createHash } from 'node:crypto'
 import type { AgentIntent } from '../intents/types'
+import {
+  FISCAL_YEAR_RULE,
+  renderFiscalYearInventory,
+  type FiscalYearInventoryRow,
+} from '@/lib/agent/fiscal-years'
 
 // Builds the system prompt the chat loop sends to Anthropic.
 //
@@ -41,6 +46,9 @@ interface BuildArgs {
   // relative-time reasoning ("förra månaden", "förfallen", current VAT period)
   // to the real date instead of the model's training cutoff. See swedishToday().
   today: string
+  // The company's räkenskapsår, newest first (lib/agent/fiscal-years.ts).
+  // Optional so a caller that has nothing to say renders no section.
+  fiscalYears?: FiscalYearInventoryRow[]
   supabase: SupabaseClient
 }
 
@@ -213,7 +221,7 @@ async function resolveBodies(
 }
 
 export function buildIdentityBlock(args: BuildArgs): string {
-  const { intent, companyName, firstName, profileSummary, rankedMemory, vatStatus, today } = args
+  const { intent, companyName, firstName, profileSummary, rankedMemory, vatStatus, today, fiscalYears } = args
 
   const lines: string[] = []
   lines.push('# Din roll')
@@ -392,6 +400,20 @@ export function buildIdentityBlock(args: BuildArgs): string {
   lines.push('4. **Inga hypoteser om motsatt status.** Spekulera ALDRIG "om du *varit* momsregistrerad hade det blivit X" eller "om du *inte varit* momsregistrerad…": det är källan till hallucinationer mellan turns. Svara för det faktiska tillståndet enligt blocket "Företagets momsstatus" ovan. Om användaren vill ha en hypotetisk genomgång: säg att de kan ändra status i /settings/company och prova om.')
   lines.push('')
 
+  // Which years the ledger holds. The report tools default to the most recent
+  // period, so without this inventory a multi-year ledger read as single-year
+  // to the model and the user concluded the assistant "only sees the period I
+  // am standing in" (#2185). Always-on rather than first-message: the question
+  // about an earlier year tends to come many turns in.
+  const fiscalYearLine = renderFiscalYearInventory(fiscalYears ?? [])
+  if (fiscalYearLine) {
+    lines.push('# Räkenskapsår')
+    lines.push('')
+    lines.push(fiscalYearLine)
+    lines.push(FISCAL_YEAR_RULE)
+    lines.push('')
+  }
+
   if (profileSummary) {
     lines.push('# Företagets profil')
     lines.push('')