diff --git a/src/conversationRuntime.js b/src/conversationRuntime.js
index 8fb442b..3a7879c 100644
--- a/src/conversationRuntime.js
+++ b/src/conversationRuntime.js
@@ -31,8 +31,8 @@ export async function resolveConversationRuntime({
       forceNewTask,
       memorySlots,
       classifier,
-      ...(maxInheritTurns ? { maxInheritTurns } : {}),
-      ...(maxInheritedSlots ? { maxInheritedSlots } : {}),
+      ...(maxInheritTurns != null ? { maxInheritTurns } : {}),
+      ...(maxInheritedSlots != null ? { maxInheritedSlots } : {}),
     },
   );
   conversationContext = await refineTurnContextWithHarness({
diff --git a/src/turnContext.js b/src/turnContext.js
index 3c83473..d8e53f2 100644
--- a/src/turnContext.js
+++ b/src/turnContext.js
@@ -25,7 +25,10 @@ const SLOT_LABELS = {
   dimensions: '维度',
   analysisMode: '分析方式',
 };
-const TIME_PATTERN = /(?:近|最近|过去)\s*(?:\d+|[一二两三四五六七八九十]+)\s*个?(?:天|日|周|星期|月|季度|年)|(?:本|这|上|下)(?:个)?(?:周|星期|月|季度|年)|(?:今天|今日|昨天|昨日|前天|明天|后天|今年|去年|明年)|(?:第[一二三四1-4]季度|Q[1-4])|\d{4}年(?:\d{1,2}月)?|\d{1,2}月/gi;
+const EXPLICIT_DATE_PATTERN = String.raw`(?:\d{4}年)?\d{1,2}月\d{1,2}[日号]|\d{4}[-/.]\d{1,2}[-/.]\d{1,2}`;
+// Match complete day ranges before their year/month prefixes so inheritance keeps day precision.
+const EXPLICIT_DATE_RANGE_PATTERN = String.raw`(?:${EXPLICIT_DATE_PATTERN})(?:\s*(?:到|至|~|—|－|-)\s*(?:${EXPLICIT_DATE_PATTERN}|\d{1,2}[日号]))?`;
+const TIME_PATTERN = new RegExp(String.raw`${EXPLICIT_DATE_RANGE_PATTERN}|(?:近|最近|过去)\s*(?:\d+|[一二两三四五六七八九十]+)\s*个?(?:天|日|周|星期|月|季度|年)|(?:本|这|上|下)(?:个)?(?:周|星期|月|季度|年)|(?:今天|今日|昨天|昨日|前天|明天|后天|今年|去年|明年)|(?:第[一二三四1-4]季度|Q[1-4])|\d{4}年(?:\d{1,2}月)?|\d{1,2}月`, 'gi');
 const TIME_HINT_PATTERN = /(?:近|最近|过去)\s*(?:\d+|[一二两三四五六七八九十]+)\s*个?(?:天|日|周|星期|月|季度|年)|(?:本|这|上|下)(?:个)?(?:周|星期|月|季度|年)|今天|今日|昨天|昨日|前天|明天|后天|今年|去年|明年|第[一二三四1-4]季度|Q[1-4]|\d{4}年|\d{1,2}月/i;
 const FILTER_PATTERN = /(?:只看|仅看|限定|过滤|筛选|排除)([^，。；,;]{1,24})/g;
 const TIME_GRAINS = new Set(['日', '天', '周', '月', '季度', '年']);
@@ -231,7 +234,7 @@ export function inferClarificationSlots(question) {
     return {};
   }
   const slots = {};
-  if (TIME_HINT_PATTERN.test(source)) {
+  if (TIME_HINT_PATTERN.test(source) || extractExplicitSlots(source).time?.length) {
     return slots;
   }
   if (turnPatterns().fieldLabel?.test(source)) {
@@ -514,7 +517,7 @@ export function createTurnContext({
       inheritedSlots,
       memorySlots: usableMemorySlots,
       clearedSlots: cleared,
-      result: previousTask?.result ?? null,
+      result: canInherit ? previousTask?.result ?? null : null,
       status: 'PLANNING',
       createdAt: new Date().toISOString(),
       updatedAt: new Date().toISOString(),
diff --git a/tests/conversationRuntimeBudgets.test.js b/tests/conversationRuntimeBudgets.test.js
new file mode 100644
index 0000000..7df5655
--- /dev/null
+++ b/tests/conversationRuntimeBudgets.test.js
@@ -0,0 +1,117 @@
+import assert from 'node:assert/strict';
+import test from 'node:test';
+
+import { resolveConversationRuntime } from '../src/conversationRuntime.js';
+import { SessionMemoryStore } from '../src/memory.js';
+import { completeTaskState, createTurnContext, TURN_TYPES } from '../src/turnContext.js';
+
+function salesMemory({ inheritDepth = 0 } = {}) {
+  const initial = createTurnContext({ question: '查询销售额，本月，只看华东' });
+  const taskState = completeTaskState({
+    contextTask: { ...initial.taskState, inheritDepth },
+    answer: {
+      resolvedQuestion: initial.question,
+      queryFingerprint: 'sales-fingerprint-123',
+      dataHash: 'sales-data-hash-123',
+    },
+    artifactId: 'sales-artifact-123',
+    messageId: 'sales-message-123',
+  });
+  const rows = [
+    { id: 'user-123', role: 'user', content: initial.originalQuestion },
+    {
+      id: 'sales-message-123', role: 'assistant', content: '本月华东销售额为100万元。',
+      result: { question: initial.question, taskState, artifactId: 'sales-artifact-123' },
+    },
+  ];
+  const memory = new SessionMemoryStore({
+    getChatSession: () => ({ id: 'session-123', themeId: 'sales' }),
+    listChatMessages: () => rows,
+  });
+  return { memory, taskState };
+}
+
+async function resolveBudget(options = {}, fixtureOptions = {}) {
+  const { memory, taskState } = salesMemory(fixtureOptions);
+  const runtime = await resolveConversationRuntime({
+    memory,
+    sessionId: 'session-123',
+    userId: 'user-123',
+    question: '那按渠道拆开呢',
+    classifier: false,
+    harness: { mode: 'local-rule' },
+    ...options,
+  });
+  return { ...runtime, previousTask: taskState };
+}
+
+test('runtime zero turn budget starts a clean execution task despite completed history', async () => {
+  const { conversationContext: context, executionContext, understanding, previousTask } =
+    await resolveBudget({ maxInheritTurns: 0 });
+
+  assert.equal(understanding.turns[1].taskState.result.artifactId, 'sales-artifact-123');
+  assert.equal(context.turnType, TURN_TYPES.NEW_TASK);
+  assert.equal(context.reason, 'task_context_expired');
+  assert.notEqual(context.taskId, previousTask.taskId);
+  assert.deepEqual(context.inheritedSlots, {});
+  assert.equal(context.taskState.result, null);
+  assert.equal(executionContext.taskState.result, null);
+  assert.deepEqual(executionContext.messages, []);
+  assert.doesNotMatch(executionContext.sourceContext, /本月|华东|销售额|sales-(?:artifact|fingerprint|data-hash|message)-123/);
+  assert.doesNotMatch(executionContext.systemMessage.content, /sales-(?:artifact|fingerprint|data-hash|message)-123/);
+});
+
+test('runtime zero slot budget excludes prior conditions from the execution contract', async () => {
+  const { conversationContext: context, executionContext, previousTask } =
+    await resolveBudget({ maxInheritedSlots: 0 });
+
+  assert.equal(context.turnType, TURN_TYPES.CONTINUATION);
+  assert.equal(context.taskId, previousTask.taskId);
+  assert.deepEqual(context.inheritedSlots, {});
+  assert.equal(context.inheritQueryContext, false);
+  assert.doesNotMatch(executionContext.sourceContext, /本月|华东|销售额/);
+  assert.match(executionContext.sourceContext, /渠道/);
+  assert.equal(context.taskState.result.artifactId, 'sales-artifact-123');
+});
+
+for (const { name, options } of [
+  { name: 'omitted', options: {} },
+  { name: 'undefined', options: { maxInheritTurns: undefined, maxInheritedSlots: undefined } },
+  { name: 'null', options: { maxInheritTurns: null, maxInheritedSlots: null } },
+]) {
+  test(`runtime ${name} budgets retain default inheritance`, async () => {
+    const { conversationContext: context, executionContext } = await resolveBudget(options);
+
+    assert.equal(context.turnType, TURN_TYPES.CONTINUATION);
+    assert.equal(context.inheritBudget.maxTurns, 4);
+    assert.equal(context.inheritBudget.maxSlots, 3);
+    assert.deepEqual(Object.keys(context.inheritedSlots), ['metric', 'time', 'filters']);
+    for (const condition of ['销售额', '本月', '华东']) {
+      assert.ok(executionContext.sourceContext.includes(condition));
+    }
+  });
+}
+
+test('runtime positive budgets limit inherited slots and allow remaining turns', async () => {
+  const { conversationContext: context, executionContext } = await resolveBudget({
+    maxInheritTurns: 2, maxInheritedSlots: 1,
+  }, { inheritDepth: 1 });
+
+  assert.equal(context.turnType, TURN_TYPES.CONTINUATION);
+  assert.equal(context.inheritBudget.usedTurns, 2);
+  assert.equal(context.inheritBudget.remainingTurns, 0);
+  assert.deepEqual(Object.keys(context.inheritedSlots), ['metric']);
+  assert.match(executionContext.sourceContext, /销售额/);
+  assert.doesNotMatch(executionContext.sourceContext, /本月|华东/);
+});
+
+test('runtime positive turn budget expires at its configured depth', async () => {
+  const { conversationContext: context, executionContext } = await resolveBudget({
+    maxInheritTurns: 1, maxInheritedSlots: 1,
+  }, { inheritDepth: 1 });
+
+  assert.equal(context.turnType, TURN_TYPES.NEW_TASK);
+  assert.equal(context.reason, 'task_context_expired');
+  assert.deepEqual(context.inheritedSlots, {});
+  assert.equal(executionContext.taskState.result, null);
+});
diff --git a/tests/postgresql.query.http.test.js b/tests/postgresql.query.http.test.js
index 32f4b11..d7ee04a 100644
--- a/tests/postgresql.query.http.test.js
+++ b/tests/postgresql.query.http.test.js
@@ -122,7 +122,7 @@ test('live PostgreSQL: authenticated Agent contract, row policy, audit and same-
         });
         assert.equal(streamed.status, 200);
         const events = (await streamed.text()).trim().split('\n').map((line) => JSON.parse(line));
-        assert.ok(!events.some((event) => event.type === 'stream_error'), JSON.stringify(events));
+        assert.deepEqual(events.filter((event) => event.type === 'stream_error'), []);
         const success = { response: streamed, data: events.find((event) => event.type === 'final')?.answer };
         assert.equal(success.response.status, 200, JSON.stringify(success.data));
         assert.ok(success.data);
diff --git a/tests/queryDateRange.http.test.js b/tests/queryDateRange.http.test.js
new file mode 100644
index 0000000..36b7196
--- /dev/null
+++ b/tests/queryDateRange.http.test.js
@@ -0,0 +1,86 @@
+import assert from 'node:assert/strict';
+import test from 'node:test';
+import { withSkillServer } from './fixtures/skillServer.js';
+
+test('authenticated streaming contracts keep explicit date ranges intact and apply row policy', async () => {
+  await withSkillServer(async ({ application, login, baseUrl }) => {
+    const cookie = await login('east_manager');
+    const user = application.database.getUserByUsername('east_manager');
+    const source = application.database.saveDataSource({
+      code: 'range_pg', name: 'Range PostgreSQL', dbType: 'POSTGRESQL',
+      host: 'localhost', port: 5432, databaseName: 'test', username: 'test',
+      encryptedPassword: '', options: {},
+    });
+    const dataset = application.database.saveBusinessDataset({
+      code: 'range_sales', name: 'Range sales', datasourceId: source.id,
+      schemaName: 'public', primaryTable: 'sales',
+      config: { autoLatestDateRange: false, policyFieldMap: { region: 'region' } },
+    });
+    application.database.replaceDatasetFields(dataset.id, [
+      { fieldName: 'day', dataType: 'date', semanticType: 'DATE', role: 'TIME',
+        aggregator: 'NONE', allowedOperators: ['BETWEEN'] },
+      { fieldName: 'region', dataType: 'text', semanticType: 'STRING', role: 'DIMENSION',
+        aggregator: 'NONE', allowedOperators: ['IN'] },
+      { fieldName: 'amount', dataType: 'numeric', semanticType: 'NUMBER', role: 'METRIC',
+        aggregator: 'SUM', allowedOperators: ['>', 'BETWEEN'] },
+    ]);
+    application.database.grantDatasetAccess(user.id, dataset.id, true);
+    application.database.saveTheme({ ...application.database.getTheme(1), indicatorIds: [],
+      businessDatasetIds: [dataset.id], primaryBusinessDatasetId: dataset.id,
+      semanticPolicy: {}, systemPrompt: 'amount 为销售额，使用 SUM；day 为日期，region 为区域。',
+    }, 1);
+    application.database.savePlatformSetting('supersonic.enabled', false);
+    const statements = [];
+    // Keep auth, context, compiler, SQL generation and audit real; replace only database I/O.
+    application.businessDatasets.getPoolById = () => ({ query: async (config) => {
+      statements.push(config);
+      return [[{ amount: 40 }], [{ name: 'amount' }]];
+    } });
+    application.agent.harnessFactory = { forTheme: () => ({
+      mode: 'local-rule', model: 'range-acceptance', capabilities: {},
+      run: async ({ executeTool }) => {
+        await executeTool('list_business_datasets', {});
+        await executeTool('get_business_dataset_definition', { datasetId: dataset.id });
+        const compiled = await executeTool('compile_query_contract', {
+          sourceType: 'BUSINESS_DATASET', datasetId: dataset.id,
+          conditions: [
+            { id: 'time', sourceText: '2026年1月1日至2026年3月31日', kind: 'TIME', status: 'RESOLVED' },
+            { id: 'region', sourceText: 'west', kind: 'FILTER', status: 'RESOLVED' },
+            { id: 'metric', sourceText: 'amount', kind: 'METRIC', status: 'RESOLVED' },
+          ],
+          metricFields: [{ field: 'amount', sourceText: 'amount', aggregator: 'SUM', conditionIds: ['metric'] }],
+          dimensionFields: [],
+          filterFields: [{ field: 'region', operator: 'IN', value: ['west'], sourceText: 'west', conditionIds: ['region'] }],
+          timeWindows: [{ sourceText: '2026年1月1日至2026年3月31日', dateMode: 'BETWEEN',
+            startDate: '2026-01-01', endDate: '2026-03-31', conditionIds: ['time'] }],
+          limit: 20,
+        });
+        assert.equal(compiled.valid, true, JSON.stringify(compiled.issues));
+        await executeTool('execute_query_contract', { contractId: compiled.contractId });
+        return { content: '受控查询已完成。', trace: [] };
+      },
+    }) };
+    const response = await fetch(`${baseUrl}/api/chat/query/stream`, {
+      method: 'POST', headers: { Cookie: cookie, 'Content-Type': 'application/json' },
+      body: JSON.stringify({ themeId: 1, question: '2026年1月1日至2026年3月31日 west amount' }),
+    });
+    assert.equal(response.status, 200);
+    const events = (await response.text()).trim().split('\n').map(line => JSON.parse(line));
+    assert.deepEqual(events.filter(event => event.type === 'stream_error'), []);
+    const answer = events.find(event => event.type === 'final')?.answer;
+    assert.ok(answer);
+    assert.deepEqual(answer.data.rows, [{ amount: 40 }]);
+    const plan = application.database.getQueryPlan(answer.semanticParse.planId, user.id);
+    assert.equal(plan.status, 'EXECUTED');
+    assert.equal(plan.plan.timeWindows[0].startDate, '2026-01-01');
+    assert.equal(plan.plan.timeWindows[0].endDate, '2026-03-31');
+    const audit = application.database.listDatasetQueryLogs(100).filter(log => log.datasetId === dataset.id);
+    assert.equal(audit.length, 1);
+    const statement = statements.find(item => item.sql === audit[0].sqlText);
+    assert.ok(statement);
+    assert.ok(statement.values.includes('2026-01-01'));
+    assert.ok(statement.values.includes('2026-03-31'));
+    assert.ok(statement.values.flat(Infinity).includes('华东'));
+    assert.ok(!statement.values.flat(Infinity).includes('west'));
+  });
+});
diff --git a/tests/taskResultBoundary.test.js b/tests/taskResultBoundary.test.js
new file mode 100644
index 0000000..3ce445e
--- /dev/null
+++ b/tests/taskResultBoundary.test.js
@@ -0,0 +1,96 @@
+import assert from 'node:assert/strict';
+import test from 'node:test';
+
+import { resolveConversationContext } from '../src/conversationResolver.js';
+import {
+  TURN_TYPES,
+  completeTaskState,
+  createTurnContext,
+  formatTaskForPrompt,
+  publicContextDecision,
+  serializeTaskForContract,
+} from '../src/turnContext.js';
+
+function salesHistory() {
+  const context = createTurnContext({ question: '查询本月销售额，只看华东' });
+  return [
+    { role: 'user', content: context.originalQuestion },
+    {
+      role: 'assistant',
+      content: '本月华东销售额为100万元。',
+      result: {
+        taskState: completeTaskState({
+          contextTask: context.taskState,
+          answer: {
+            resolvedQuestion: context.question,
+            queryFingerprint: 'sales-fingerprint-123',
+            dataHash: 'sales-data-hash-123',
+          },
+          artifactId: 'sales-artifact-123',
+          messageId: 'sales-message-123',
+        }),
+      },
+    },
+  ];
+}
+
+for (const { name, question, options, extraHistory = [], reason } of [
+  { name: 'explicit new question', question: '新问题，查询今年订单量',
+    reason: 'explicit_new_task' },
+  { name: 'forced task reset', question: '那按渠道拆开呢',
+    options: { forceNewTask: true }, reason: 'forced_new_task' },
+  { name: 'zero inheritance budget', question: '那按渠道拆开呢',
+    options: { maxInheritTurns: 0 }, reason: 'task_context_expired' },
+  { name: 'elapsed history budget', question: '那按渠道拆开呢',
+    options: { maxInheritTurns: 1 }, reason: 'task_context_expired',
+    extraHistory: [
+      { role: 'user', content: '谢谢' },
+      { role: 'assistant', content: '不客气' },
+      { role: 'user', content: '好的' },
+    ] },
+]) {
+  test(`${name} clears prior result from task state, prompt and execution contract`, () => {
+    const history = [...salesHistory(), ...extraHistory];
+    const context = resolveConversationContext(question, history, options);
+
+    assert.equal(context.turnType, TURN_TYPES.NEW_TASK);
+    assert.equal(context.reason, reason);
+    assert.notEqual(context.taskId, history[1].result.taskState.taskId);
+    assert.deepEqual(context.inheritedSlots, {});
+    assert.equal(publicContextDecision(context).referencedArtifactId, null);
+    assert.equal(context.taskState.result, null);
+    for (const serialized of [
+      JSON.stringify(context.taskState),
+      formatTaskForPrompt(context.taskState),
+      serializeTaskForContract(context.taskState),
+    ]) {
+      assert.doesNotMatch(serialized, /sales-(?:artifact|fingerprint|data-hash|message)-123/);
+    }
+  });
+}
+
+for (const { question, turnType, referencedArtifactId } of [
+  { question: '那按渠道拆开呢', turnType: TURN_TYPES.CONTINUATION,
+    referencedArtifactId: null },
+  { question: '导出Excel', turnType: TURN_TYPES.RESULT_OPERATION,
+    referencedArtifactId: 'sales-artifact-123' },
+  { question: '上述结果按渠道拆开', turnType: TURN_TYPES.CONTINUATION,
+    referencedArtifactId: 'sales-artifact-123' },
+]) {
+  test(`${question} preserves the eligible result and its lineage`, () => {
+    const history = salesHistory();
+    const context = resolveConversationContext(question, history);
+
+    assert.equal(context.turnType, turnType);
+    assert.equal(context.taskId, history[1].result.taskState.taskId);
+    assert.equal(publicContextDecision(context).referencedArtifactId, referencedArtifactId);
+    assert.deepEqual(context.taskState.result, {
+      artifactId: 'sales-artifact-123',
+      messageId: 'sales-message-123',
+      queryFingerprint: 'sales-fingerprint-123',
+      dataHash: 'sales-data-hash-123',
+    });
+    assert.match(formatTaskForPrompt(context.taskState), /sales-artifact-123/);
+    assert.match(serializeTaskForContract(context.taskState), /sales-artifact-123/);
+  });
+}
diff --git a/tests/turnContext.test.js b/tests/turnContext.test.js
index f7e7117..8282a36 100644
--- a/tests/turnContext.test.js
+++ b/tests/turnContext.test.js
@@ -31,6 +31,46 @@ function completedHistory(context, content = '查询已完成') {
   ];
 }
 
+for (const time of [
+  '2026年1月1日至2026年3月31日',
+  '2026-01-01 至 2026-03-31',
+  '2026年1月1日至3月31日',
+  '2026年1月1日',
+]) {
+  test(`explicit time slots preserve the complete date expression: ${time}`, () => {
+    assert.deepEqual(extractExplicitSlots(`${time}销售额`).time.map(item => item.sourceText), [time]);
+  });
+}
+
+test('two distinct explicit date ranges remain separate time slots', () => {
+  const question = '对比2026年1月1日至2026年1月31日与2026年3月1日至2026年3月31日销售额';
+  assert.deepEqual(extractExplicitSlots(question).time.map(item => item.sourceText), [
+    '2026年1月1日至2026年1月31日', '2026年3月1日至2026年3月31日',
+  ]);
+});
+
+test('an ISO date clarification fills time without replacing the inherited region filter', () => {
+  const first = createTurnContext({ question: '销售额，只看华东' });
+  const clarified = createTurnContext({ question: '2026-01-01', history: completedHistory(first),
+    turnType: TURN_TYPES.CLARIFICATION_ANSWER });
+  assert.deepEqual(clarified.slots.time.map(item => item.sourceText), ['2026-01-01']);
+  assert.equal(clarified.explicitSlots.filters, undefined);
+  assert.deepEqual(clarified.inheritedSlots.filters.map(item => item.sourceText), ['华东']);
+  assert.deepEqual(clarified.slots.filters.map(item => item.sourceText), ['华东']);
+});
+
+test('followups inherit full date ranges and filters while a time revision replaces only time', () => {
+  const first = createTurnContext({ question: '2026年1月1日至2026年3月31日销售额，只看华东' });
+  const second = createTurnContext({ question: '按渠道拆开', history: completedHistory(first),
+    turnType: TURN_TYPES.CONTINUATION });
+  assert.deepEqual(second.inheritedSlots.time.map(item => item.sourceText), ['2026年1月1日至2026年3月31日']);
+  assert.deepEqual(second.inheritedSlots.filters.map(item => item.sourceText), ['华东']);
+  const revised = createTurnContext({ question: '改查2026年4月1日至2026年4月15日',
+    history: completedHistory(second), turnType: TURN_TYPES.REVISION });
+  assert.deepEqual(revised.slots.time.map(item => item.sourceText), ['2026年4月1日至2026年4月15日']);
+  assert.deepEqual(revised.inheritedSlots.filters.map(item => item.sourceText), ['华东']);
+});
+
 test('continuations keep the task id, advance the turn id and inherit field by field', () => {
   const first = createTurnContext({
     question: '查询本月含税销售金额',