diff --git a/apps/csbie-server/src/routes/mcp.ts b/apps/csbie-server/src/routes/mcp.ts
index b3e898b..b932552 100644
--- a/apps/csbie-server/src/routes/mcp.ts
+++ b/apps/csbie-server/src/routes/mcp.ts
@@ -194,14 +194,16 @@ const boardOptionsSchema = issueOptionsSchema.extend({
     .optional(),
 })
 
-const stockOrderBaseSchema = z.object({
-  issueCode: issueCodeSchema,
-  market: marketCodeSchema,
-  side: tradeSideSchema,
-  accountType: accountTypeSchema.optional(),
-  quantity: z.number().positive().describe('Order quantity'),
-  depositType: depositTypeSchema.optional(),
-})
+const stockOrderBaseSchema = z
+  .object({
+    issueCode: issueCodeSchema,
+    market: marketCodeSchema,
+    side: tradeSideSchema,
+    accountType: accountTypeSchema.optional(),
+    quantity: z.number().positive().describe('Order quantity'),
+    depositType: depositTypeSchema.optional(),
+  })
+  .strict()
 
 const cashOrderPriceConditionSchema = z.enum([
   'limit',
@@ -218,9 +220,14 @@ const cashOrderPriceConditionSchema = z.enum([
 const cashOrderSchema = stockOrderBaseSchema.extend({
   preOrderMarket: marketCodeSchema
     .optional()
-    .describe('APK pre-order market for S-kabu; live S-kabu orders still send STK'),
+    .describe(
+      'Original listed market for S-kabu checks, such as XTKS. For S-kabu live orders set kind: "s", market: "STK", and preOrderMarket to the listed market.',
+    ),
   price: z.number().positive().optional().describe('Order price for price-based orders'),
-  kind: z.enum(['market', 'limit', 'stop', 'oco', 'ifd', 'ifdo', 's', 'unknown']).optional(),
+  kind: z
+    .enum(['market', 'limit', 'stop', 'oco', 'ifd', 'ifdo', 's', 'unknown'])
+    .optional()
+    .describe('Use "s" for S-kabu fractional-share cash orders. Do not use sStock.'),
   priceCondition: cashOrderPriceConditionSchema
     .optional()
     .describe('APK/MTS execution condition for cash orders'),
@@ -245,31 +252,42 @@ const cashOrderSchema = stockOrderBaseSchema.extend({
     .describe('Previous market code sent with SOR orders; defaults to login profile'),
 })
 
-const cashOrderPreOrderSchema = z.object({
-  issueCode: issueCodeSchema,
-  market: marketCodeSchema,
-  side: tradeSideSchema,
-  accountType: accountTypeSchema.optional(),
-  depositType: depositTypeSchema.optional(),
-  kind: z.enum(['s']).optional().describe('Requests APK S-kabu pre-order constraints'),
-  preOrderMarket: marketCodeSchema.optional().describe('APK pre-order market for S-kabu checks'),
-})
+const cashOrderPreOrderSchema = z
+  .object({
+    issueCode: issueCodeSchema,
+    market: marketCodeSchema,
+    side: tradeSideSchema,
+    accountType: accountTypeSchema.optional(),
+    depositType: depositTypeSchema.optional(),
+    kind: z
+      .enum(['s'])
+      .optional()
+      .describe('Set to "s" to request APK S-kabu pre-order constraints. Do not use sStock.'),
+    preOrderMarket: marketCodeSchema
+      .optional()
+      .describe('Original listed market for S-kabu preflight, such as XTKS.'),
+  })
+  .strict()
 
-const stockOrderMarginPositionSchema = z.object({
-  openTradeDate: z
-    .string()
-    .describe('Open trade date from the margin position record, in yyyyMMdd or yyyy-MM-dd format'),
-  openPrice: z
-    .union([z.number().positive(), z.string().min(1)])
-    .describe('Open price from the margin position record'),
-  quantity: z
-    .union([z.number().positive(), z.string().min(1)])
-    .describe('Selected quantity from the margin position record'),
-  orgNewTradeDate: z.string().describe('Original new-trade date from the margin position record'),
-  bargainMarketCode: marketCodeSchema.describe(
-    'Bargain market code from the margin position record',
-  ),
-})
+const stockOrderMarginPositionSchema = z
+  .object({
+    openTradeDate: z
+      .string()
+      .describe(
+        'Open trade date from the margin position record, in yyyyMMdd or yyyy-MM-dd format',
+      ),
+    openPrice: z
+      .union([z.number().positive(), z.string().min(1)])
+      .describe('Open price from the margin position record'),
+    quantity: z
+      .union([z.number().positive(), z.string().min(1)])
+      .describe('Selected quantity from the margin position record'),
+    orgNewTradeDate: z.string().describe('Original new-trade date from the margin position record'),
+    bargainMarketCode: marketCodeSchema.describe(
+      'Bargain market code from the margin position record',
+    ),
+  })
+  .strict()
 
 const placeCashOrderSchema = cashOrderSchema.extend({
   confirmationId: z
@@ -283,48 +301,50 @@ const placeCashOrderSchema = cashOrderSchema.extend({
   allowTrading: z.literal(true).optional().describe('Explicitly allows sending a live order'),
 })
 
-const orderCorrectionSchema = z.object({
-  orderNumber: z
-    .string()
-    .min(1)
-    .optional()
-    .describe('Order number shown in order inquiry; required by the mobile pre-correction route'),
-  orderId: orderIdSchema,
-  issueCode: issueCodeSchema.optional().describe('Issue code from the pre-correction response'),
-  market: marketCodeSchema.optional().describe('Market code from the pre-correction response'),
-  tradeId: z.string().min(1).optional().describe('Original trade id code'),
-  correctionType: z.string().min(1).optional().describe('Additional correction flag'),
-  status: z.string().min(1).optional().describe('Original order status code'),
-  rbeOrderStatus: z.string().min(1).optional().describe('Original RBE order status code'),
-  depositTypeText: z.string().min(1).optional().describe('Display deposit type text'),
-  orderMethod: z.enum(['normal', 'stop', 'oco']).optional().describe('Primary order method'),
-  priceCondition: cashOrderPriceConditionSchema
-    .optional()
-    .describe('Corrected primary execution condition'),
-  triggerZone: z.enum(['above', 'below']).optional().describe('Stop trigger direction'),
-  triggerPrice: z.number().positive().optional().describe('Stop trigger price'),
-  secondaryPriceCondition: cashOrderPriceConditionSchema
-    .optional()
-    .describe('Secondary/OCO execution condition'),
-  secondaryPrice: z.number().positive().optional().describe('Secondary/OCO price'),
-  ifdPriceCondition: cashOrderPriceConditionSchema
-    .optional()
-    .describe('IFD follow-up execution condition for IF/IFDOCO correction'),
-  ifdPrice: z.number().positive().optional().describe('IFD follow-up price'),
-  ifdOrderMethod: z
-    .enum(['normal', 'stop', 'oco'])
-    .optional()
-    .describe('IFD follow-up special order method'),
-  ifdTriggerZone: z.enum(['above', 'below']).optional().describe('IFD stop trigger direction'),
-  ifdTriggerPrice: z.number().positive().optional().describe('IFD stop trigger price'),
-  ifdSecondaryPriceCondition: cashOrderPriceConditionSchema
-    .optional()
-    .describe('IFD secondary/OCO execution condition'),
-  ifdSecondaryPrice: z.number().positive().optional().describe('IFD secondary/OCO price'),
-  correctionControlFlag: z.enum(['1', '2']).optional().describe('Mobile correction control flag'),
-  quantity: z.number().positive().optional().describe('Corrected order quantity'),
-  price: z.number().positive().optional().describe('Corrected order price'),
-})
+const orderCorrectionSchema = z
+  .object({
+    orderNumber: z
+      .string()
+      .min(1)
+      .optional()
+      .describe('Order number shown in order inquiry; required by the mobile pre-correction route'),
+    orderId: orderIdSchema,
+    issueCode: issueCodeSchema.optional().describe('Issue code from the pre-correction response'),
+    market: marketCodeSchema.optional().describe('Market code from the pre-correction response'),
+    tradeId: z.string().min(1).optional().describe('Original trade id code'),
+    correctionType: z.string().min(1).optional().describe('Additional correction flag'),
+    status: z.string().min(1).optional().describe('Original order status code'),
+    rbeOrderStatus: z.string().min(1).optional().describe('Original RBE order status code'),
+    depositTypeText: z.string().min(1).optional().describe('Display deposit type text'),
+    orderMethod: z.enum(['normal', 'stop', 'oco']).optional().describe('Primary order method'),
+    priceCondition: cashOrderPriceConditionSchema
+      .optional()
+      .describe('Corrected primary execution condition'),
+    triggerZone: z.enum(['above', 'below']).optional().describe('Stop trigger direction'),
+    triggerPrice: z.number().positive().optional().describe('Stop trigger price'),
+    secondaryPriceCondition: cashOrderPriceConditionSchema
+      .optional()
+      .describe('Secondary/OCO execution condition'),
+    secondaryPrice: z.number().positive().optional().describe('Secondary/OCO price'),
+    ifdPriceCondition: cashOrderPriceConditionSchema
+      .optional()
+      .describe('IFD follow-up execution condition for IF/IFDOCO correction'),
+    ifdPrice: z.number().positive().optional().describe('IFD follow-up price'),
+    ifdOrderMethod: z
+      .enum(['normal', 'stop', 'oco'])
+      .optional()
+      .describe('IFD follow-up special order method'),
+    ifdTriggerZone: z.enum(['above', 'below']).optional().describe('IFD stop trigger direction'),
+    ifdTriggerPrice: z.number().positive().optional().describe('IFD stop trigger price'),
+    ifdSecondaryPriceCondition: cashOrderPriceConditionSchema
+      .optional()
+      .describe('IFD secondary/OCO execution condition'),
+    ifdSecondaryPrice: z.number().positive().optional().describe('IFD secondary/OCO price'),
+    correctionControlFlag: z.enum(['1', '2']).optional().describe('Mobile correction control flag'),
+    quantity: z.number().positive().optional().describe('Corrected order quantity'),
+    price: z.number().positive().optional().describe('Corrected order price'),
+  })
+  .strict()
 
 const placeOrderCorrectionSchema = orderCorrectionSchema.extend({
   allowTrading: z
@@ -333,14 +353,16 @@ const placeOrderCorrectionSchema = orderCorrectionSchema.extend({
     .describe('Explicitly allows sending a live correction request'),
 })
 
-const orderCancelSchema = z.object({
-  orderNumber: z.string().min(1).describe('Order number shown in order inquiry'),
-  orderId: orderIdSchema.optional().describe('Original order id shown in order inquiry'),
-  issueCode: issueCodeSchema.optional().describe('Original issue code shown in order inquiry'),
-  market: marketCodeSchema.optional().describe('Original market code shown in order inquiry'),
-  tradeId: z.string().min(1).optional().describe('Original trade id code'),
-  cancelType: z.string().min(1).optional().describe('Additional cancel flag'),
-})
+const orderCancelSchema = z
+  .object({
+    orderNumber: z.string().min(1).describe('Order number shown in order inquiry'),
+    orderId: orderIdSchema.optional().describe('Original order id shown in order inquiry'),
+    issueCode: issueCodeSchema.optional().describe('Original issue code shown in order inquiry'),
+    market: marketCodeSchema.optional().describe('Original market code shown in order inquiry'),
+    tradeId: z.string().min(1).optional().describe('Original trade id code'),
+    cancelType: z.string().min(1).optional().describe('Additional cancel flag'),
+  })
+  .strict()
 
 const placeOrderCancelSchema = orderCancelSchema.extend({
   tradePassword: z.string().optional().describe('Trading password used by SBI'),
@@ -423,24 +445,26 @@ const placeMarginCloseOrderSchema = marginCloseOrderSchema.extend({
     .describe('Explicitly allows sending a live margin close order'),
 })
 
-const actualDeliveryOrderSchema = z.object({
-  issueCode: issueCodeSchema,
-  market: marketCodeSchema,
-  accountType: accountTypeSchema.optional(),
-  quantity: z.number().positive().describe('Order quantity'),
-  depositType: depositTypeSchema.optional(),
-  price: z.number().positive().optional().describe('Order price for price-based requests'),
-  kind: z.enum(['genbiki', 'genwatashi']),
-  positionId: positionIdSchema.optional().describe('Position ID to deliver'),
-  marginPositions: z
-    .array(stockOrderMarginPositionSchema)
-    .optional()
-    .describe('Margin position records selected for genbiki/genwatashi delivery'),
-  ippanMarginPaymentLimit: z
-    .string()
-    .optional()
-    .describe('APK ippan margin payment-limit code from board/pre-order information'),
-})
+const actualDeliveryOrderSchema = z
+  .object({
+    issueCode: issueCodeSchema,
+    market: marketCodeSchema,
+    accountType: accountTypeSchema.optional(),
+    quantity: z.number().positive().describe('Order quantity'),
+    depositType: depositTypeSchema.optional(),
+    price: z.number().positive().optional().describe('Order price for price-based requests'),
+    kind: z.enum(['genbiki', 'genwatashi']),
+    positionId: positionIdSchema.optional().describe('Position ID to deliver'),
+    marginPositions: z
+      .array(stockOrderMarginPositionSchema)
+      .optional()
+      .describe('Margin position records selected for genbiki/genwatashi delivery'),
+    ippanMarginPaymentLimit: z
+      .string()
+      .optional()
+      .describe('APK ippan margin payment-limit code from board/pre-order information'),
+  })
+  .strict()
 
 const actualDeliveryOrderPreOrderSchema = actualDeliveryOrderSchema.omit({
   quantity: true,
@@ -517,50 +541,58 @@ const placeIfdOrderSchema = ifdOrderSchema.extend({
   allowTrading: z.literal(true).optional().describe('Explicitly allows sending a live IFD order'),
 })
 
-const themeInvestmentOrderSchema = z.object({
-  themeId: z.string().min(1).describe('Theme ID for the theme investment order'),
-  themeSetYyyymm: z
-    .string()
-    .length(6)
-    .describe('Theme set year/month (`theme_set_yyyymm`) from the mobile APK handoff'),
-  themeCourse: z
-    .union([z.number().int().nonnegative(), z.string().min(1).max(2)])
-    .describe('Theme course (`theme_course`) from the mobile APK handoff'),
-  side: tradeSideSchema,
-  accountType: accountTypeSchema.optional().describe('Account/deposit type used for the order'),
-  depositType: accountTypeSchema.optional().describe('Deposit type used for the order'),
-  components: z
-    .array(
-      z.object({
-        issueCode: issueCodeSchema,
-        quantity: z.union([z.number().positive(), z.string().min(1)]),
-      }),
-    )
-    .min(1)
-    .max(10)
-    .describe('Component stock orders selected by the mobile theme investment flow'),
-  amount: z.number().positive().optional().describe('Order amount for the theme investment order'),
-})
+const themeInvestmentOrderSchema = z
+  .object({
+    themeId: z.string().min(1).describe('Theme ID for the theme investment order'),
+    themeSetYyyymm: z
+      .string()
+      .length(6)
+      .describe('Theme set year/month (`theme_set_yyyymm`) from the mobile APK handoff'),
+    themeCourse: z
+      .union([z.number().int().nonnegative(), z.string().min(1).max(2)])
+      .describe('Theme course (`theme_course`) from the mobile APK handoff'),
+    side: tradeSideSchema,
+    accountType: accountTypeSchema.optional().describe('Account/deposit type used for the order'),
+    depositType: accountTypeSchema.optional().describe('Deposit type used for the order'),
+    components: z
+      .array(
+        z.object({
+          issueCode: issueCodeSchema,
+          quantity: z.union([z.number().positive(), z.string().min(1)]),
+        }),
+      )
+      .min(1)
+      .max(10)
+      .describe('Component stock orders selected by the mobile theme investment flow'),
+    amount: z
+      .number()
+      .positive()
+      .optional()
+      .describe('Order amount for the theme investment order'),
+  })
+  .strict()
 
-const themeInvestmentPreOrderSchema = z.object({
-  themeId: z.string().min(1).describe('Theme ID from the mobile theme investment handoff'),
-  themeName: z
-    .string()
-    .min(1)
-    .optional()
-    .describe('Theme name from the mobile theme investment handoff'),
-  exchangeCode: marketCodeSchema.describe('Exchange code used by the mobile pre-order call'),
-  components: z
-    .array(
-      z.object({
-        issueCode: issueCodeSchema,
-        quantity: z.union([z.number().positive(), z.string().min(1)]).optional(),
-      }),
-    )
-    .min(1)
-    .max(10)
-    .describe('Component stocks selected by the mobile theme investment flow'),
-})
+const themeInvestmentPreOrderSchema = z
+  .object({
+    themeId: z.string().min(1).describe('Theme ID from the mobile theme investment handoff'),
+    themeName: z
+      .string()
+      .min(1)
+      .optional()
+      .describe('Theme name from the mobile theme investment handoff'),
+    exchangeCode: marketCodeSchema.describe('Exchange code used by the mobile pre-order call'),
+    components: z
+      .array(
+        z.object({
+          issueCode: issueCodeSchema,
+          quantity: z.union([z.number().positive(), z.string().min(1)]).optional(),
+        }),
+      )
+      .min(1)
+      .max(10)
+      .describe('Component stocks selected by the mobile theme investment flow'),
+  })
+  .strict()
 
 const placeThemeInvestmentOrderSchema = themeInvestmentOrderSchema.extend({
   allowTrading: z
@@ -569,22 +601,24 @@ const placeThemeInvestmentOrderSchema = themeInvestmentOrderSchema.extend({
     .describe('Explicitly allows sending a live theme investment order'),
 })
 
-const exchangeOrderSchema = z.object({
-  currencyCode: z.string().min(1).describe('Currency code, such as USD'),
-  side: z.enum(['buy', 'sell']).describe('Buy or sell the foreign currency'),
-  tradeQuantity: z.union([z.number().positive(), z.string().min(1)]).describe('Order quantity'),
-  specificMethod: z
-    .enum(['foreign', 'domestic'])
-    .optional()
-    .describe('foreign for foreign-currency quantity, domestic for yen amount'),
-  accountKind: z.enum(['GENERAL', 'JR_NISA']).optional().describe('SBI exchange account kind'),
-  sellMethod: z.enum(['SELL_PART', 'SELL_ALL']).optional().describe('Required for sell orders'),
-  orderAmount: z
-    .union([z.number().positive(), z.string().min(1)])
-    .optional()
-    .describe('Hidden order amount posted to SBI; required for domestic orders'),
-  tradePassword: z.string().optional().describe('Trading password used by SBI'),
-})
+const exchangeOrderSchema = z
+  .object({
+    currencyCode: z.string().min(1).describe('Currency code, such as USD'),
+    side: z.enum(['buy', 'sell']).describe('Buy or sell the foreign currency'),
+    tradeQuantity: z.union([z.number().positive(), z.string().min(1)]).describe('Order quantity'),
+    specificMethod: z
+      .enum(['foreign', 'domestic'])
+      .optional()
+      .describe('foreign for foreign-currency quantity, domestic for yen amount'),
+    accountKind: z.enum(['GENERAL', 'JR_NISA']).optional().describe('SBI exchange account kind'),
+    sellMethod: z.enum(['SELL_PART', 'SELL_ALL']).optional().describe('Required for sell orders'),
+    orderAmount: z
+      .union([z.number().positive(), z.string().min(1)])
+      .optional()
+      .describe('Hidden order amount posted to SBI; required for domestic orders'),
+    tradePassword: z.string().optional().describe('Trading password used by SBI'),
+  })
+  .strict()
 
 const exchangeRateSchema = exchangeOrderSchema.pick({
   currencyCode: true,
@@ -732,8 +766,57 @@ const getActions = Object.keys(getActionToMethod) as Array<keyof typeof getActio
 const changeActions = Object.keys(changeActionToEstimateMethod) as Array<
   keyof typeof changeActionToEstimateMethod
 >
-const getActionSchema = z.enum(['capabilities', 'passkeys', ...getActions])
-const changeActionSchema = z.enum(changeActions)
+const getActionDescription = `Available actions: capabilities, passkeys, ${getActions
+  .map((action) => `${action}=${getActionToMethod[action]}`)
+  .join(
+    ', ',
+  )}. S-kabu preflight uses cashOrderPreflight with input.kind: "s" and input.preOrderMarket, not sStock.`
+const changeActionDescription = `Available actions: ${changeActions
+  .map((action) => `${action}=${changeActionToEstimateMethod[action]}`)
+  .join(
+    ', ',
+  )}. S-kabu cash orders use cashOrder with input.kind: "s", input.market: "STK", and input.preOrderMarket set to the listed market such as XTKS; do not use sStock, orderType, or sor.`
+
+const getToolInputSchema = z.discriminatedUnion('action', [
+  z.object({ action: z.literal('capabilities') }).strict(),
+  z.object({ action: z.literal('passkeys') }).strict(),
+  ...getActions.map((action) => {
+    const method = getActionToMethod[action]
+    const paramsSchema = methodParamSchemas[method]
+    return z
+      .object({
+        action: z.literal(action),
+        passkeyId: z.string().describe('Saved SBI passkey id'),
+        ...(paramsSchema ? { input: paramsSchema.describe(`${method} input`) } : {}),
+      })
+      .strict()
+  }),
+] as any)
+
+const changeToolInputSchema = z.discriminatedUnion(
+  'action',
+  changeActions.map((action) => {
+    const method = changeActionToEstimateMethod[action]
+    const paramsSchema = methodParamSchemas[method]
+    if (!paramsSchema) throw new Error(`${method} must have an input schema`)
+    return z
+      .object({
+        action: z.literal(action),
+        passkeyId: z.string().describe('Saved SBI passkey id'),
+        input: paramsSchema.describe(`${method} input`),
+      })
+      .strict()
+  }) as any,
+)
+
+type GetToolArgs =
+  | { action: 'capabilities' }
+  | { action: 'passkeys' }
+  | {
+      action: keyof typeof getActionToMethod
+      passkeyId: string
+      input?: unknown
+    }
 
 const parseMethodParams = (method: RpcMethod, input: unknown) => {
   const schema = methodParamSchemas[method]
@@ -863,18 +946,12 @@ const createMcpServer = (c: Context<AppBindings>) => {
     'csbie-get',
     {
       title: 'Get SBI Data',
-      description:
-        'Read SBI data through a small abstract action API. This tool never places, corrects, cancels, or otherwise changes real orders.',
-      inputSchema: {
-        action: getActionSchema.describe('Read action to perform'),
-        passkeyId: z
-          .string()
-          .optional()
-          .describe('Saved SBI passkey id. Required for SBI-backed read actions.'),
-        input: z.unknown().optional().describe('Action input object'),
-      },
+      description: `Read SBI data through a small abstract action API. This tool never places, corrects, cancels, or otherwise changes real orders. ${getActionDescription}`,
+      inputSchema: getToolInputSchema,
     },
-    async ({ action, passkeyId, input }) => {
+    async (args) => {
+      const parsedArgs = getToolInputSchema.parse(args) as GetToolArgs
+      const { action } = parsedArgs
       requireAuthenticated(auth)
 
       if (action === 'capabilities') {
@@ -890,6 +967,7 @@ const createMcpServer = (c: Context<AppBindings>) => {
 
       const method = getActionToMethod[action]
       if (!method) throw new Error(`unsupported get action: ${String(action)}`)
+      const { passkeyId, input } = parsedArgs
       if (!passkeyId) throw new Error(`${action} requires passkeyId`)
 
       const params = parseMethodParams(method, input)
@@ -901,16 +979,17 @@ const createMcpServer = (c: Context<AppBindings>) => {
     'csbie-request-change',
     {
       title: 'Create SBI Change Request',
-      description:
-        'Prepare a real SBI change by running the corresponding estimate/preview and returning a UUID. This tool never submits the change; pass the UUID to confirm-request.',
-      inputSchema: {
-        action: changeActionSchema.describe('Change action to prepare'),
-        passkeyId: z.string().describe('Saved SBI passkey id'),
-        input: z.unknown().describe('Change action input object'),
-      },
+      description: `Prepare a real SBI change by running the corresponding estimate/preview and returning a UUID. This tool never submits the change; pass the UUID to confirm-request. ${changeActionDescription}`,
+      inputSchema: changeToolInputSchema,
+    },
+    async (args) => {
+      const { action, passkeyId, input } = changeToolInputSchema.parse(args) as {
+        action: keyof typeof changeActionToEstimateMethod
+        passkeyId: string
+        input: unknown
+      }
+      return textResult(await createChangeRequest(action, passkeyId, input))
     },
-    async ({ action, passkeyId, input }) =>
-      textResult(await createChangeRequest(action, passkeyId, input)),
   )
 
   server.registerTool(