diff --git a/packages/api/src/agents/__tests__/run-summarization.test.ts b/packages/api/src/agents/__tests__/run-summarization.test.ts
index 2bc0da253a98..8c4f94d8ad93 100644
--- a/packages/api/src/agents/__tests__/run-summarization.test.ts
+++ b/packages/api/src/agents/__tests__/run-summarization.test.ts
@@ -218,7 +218,7 @@ describe('summarizationConfig field passthrough', () => {
     const agents = await callAndCapture({
       summarizationConfig: {
         enabled: true,
-        trigger: { type: 'token_count', value: 8000 },
+        trigger: { type: 'token_ratio', value: 0.8 },
         provider: 'anthropic',
         model: 'claude-3-haiku',
         parameters: { temperature: 0.2 },
@@ -233,7 +233,7 @@ describe('summarizationConfig field passthrough', () => {
     // `enabled` is not forwarded to the agent-level config — it is resolved
     // into the separate `summarizationEnabled` boolean on the agent input.
     expect(agents[0].summarizationEnabled).toBe(true);
-    expect(config.trigger).toEqual({ type: 'token_count', value: 8000 });
+    expect(config.trigger).toEqual({ type: 'token_ratio', value: 0.8 });
     expect(config.provider).toBe('anthropic');
     expect(config.model).toBe('claude-3-haiku');
     expect(config.parameters).toEqual({ temperature: 0.2 });
@@ -254,6 +254,31 @@ describe('summarizationConfig field passthrough', () => {
     expect(config.provider).toBe('openAI');
     expect(config.model).toBe('gpt-4o');
   });
+
+  it('preserves `token_ratio` trigger with `value: 0` (documented, extreme-but-valid)', async () => {
+    const agents = await callAndCapture({
+      summarizationConfig: {
+        enabled: true,
+        trigger: { type: 'token_ratio', value: 0 },
+      },
+    });
+    const config = agents[0].summarizationConfig as Record<string, unknown>;
+    expect(config.trigger).toEqual({ type: 'token_ratio', value: 0 });
+  });
+
+  it.each([
+    ['remaining_tokens', 500],
+    ['messages_to_refine', 4],
+  ] as const)('passes %s trigger through unchanged', async (type, value) => {
+    const agents = await callAndCapture({
+      summarizationConfig: {
+        enabled: true,
+        trigger: { type, value },
+      },
+    });
+    const config = agents[0].summarizationConfig as Record<string, unknown>;
+    expect(config.trigger).toEqual({ type, value });
+  });
 });
 
 // ---------------------------------------------------------------------------
diff --git a/packages/api/src/agents/run.ts b/packages/api/src/agents/run.ts
index b6b5e6a14d90..cb4eda576322 100644
--- a/packages/api/src/agents/run.ts
+++ b/packages/api/src/agents/run.ts
@@ -195,7 +195,7 @@ function shapeSummarizationConfig(
   const provider = config?.provider ?? fallbackProvider;
   const model = config?.model ?? fallbackModel;
   const trigger =
-    config?.trigger?.type && config?.trigger?.value
+    config?.trigger?.type && typeof config?.trigger?.value === 'number'
       ? { type: config.trigger.type, value: config.trigger.value }
       : undefined;
 
diff --git a/packages/data-provider/specs/config-schemas.spec.ts b/packages/data-provider/specs/config-schemas.spec.ts
index 6e76bced06ac..c5bb6639cd68 100644
--- a/packages/data-provider/specs/config-schemas.spec.ts
+++ b/packages/data-provider/specs/config-schemas.spec.ts
@@ -7,6 +7,8 @@ import {
   interfaceSchema,
   fileStorageSchema,
   fileStrategiesSchema,
+  summarizationTriggerSchema,
+  summarizationConfigSchema,
 } from '../src/config';
 import { tModelSpecPresetSchema, EModelEndpoint } from '../src/schemas';
 import { FileSources } from '../src/types/files';
@@ -502,3 +504,109 @@ describe('interfaceSchema', () => {
     expect(result.modelSelect).toBe(false);
   });
 });
+
+describe('summarizationTriggerSchema', () => {
+  it.each([
+    ['token_ratio', 0.8],
+    ['remaining_tokens', 500],
+    ['messages_to_refine', 4],
+  ] as const)('accepts documented trigger type "%s" with a sensible value', (type, value) => {
+    const result = summarizationTriggerSchema.safeParse({ type, value });
+    expect(result.success).toBe(true);
+  });
+
+  it('rejects the legacy/typoed "token_count" trigger type', () => {
+    const result = summarizationTriggerSchema.safeParse({
+      type: 'token_count',
+      value: 8000,
+    });
+    expect(result.success).toBe(false);
+  });
+
+  it('rejects unknown trigger types', () => {
+    const result = summarizationTriggerSchema.safeParse({
+      type: 'never_heard_of_it',
+      value: 1,
+    });
+    expect(result.success).toBe(false);
+  });
+
+  it('rejects negative values on any trigger type', () => {
+    expect(summarizationTriggerSchema.safeParse({ type: 'token_ratio', value: -0.5 }).success).toBe(
+      false,
+    );
+    expect(
+      summarizationTriggerSchema.safeParse({ type: 'remaining_tokens', value: -1 }).success,
+    ).toBe(false);
+    expect(
+      summarizationTriggerSchema.safeParse({ type: 'messages_to_refine', value: -1 }).success,
+    ).toBe(false);
+  });
+
+  it('rejects zero for count-based triggers where it has no meaningful effect', () => {
+    expect(
+      summarizationTriggerSchema.safeParse({ type: 'remaining_tokens', value: 0 }).success,
+    ).toBe(false);
+    expect(
+      summarizationTriggerSchema.safeParse({ type: 'messages_to_refine', value: 0 }).success,
+    ).toBe(false);
+  });
+
+  it('rejects token_ratio values > 1 to catch the "80 meant as 80%" mistake', () => {
+    expect(summarizationTriggerSchema.safeParse({ type: 'token_ratio', value: 80 }).success).toBe(
+      false,
+    );
+    expect(summarizationTriggerSchema.safeParse({ type: 'token_ratio', value: 1.01 }).success).toBe(
+      false,
+    );
+  });
+
+  it('accepts token_ratio values at the inclusive 0 and 1 bounds per docs', () => {
+    expect(summarizationTriggerSchema.safeParse({ type: 'token_ratio', value: 0 }).success).toBe(
+      true,
+    );
+    expect(summarizationTriggerSchema.safeParse({ type: 'token_ratio', value: 1 }).success).toBe(
+      true,
+    );
+  });
+
+  it('allows remaining_tokens and messages_to_refine values above 1 (token/message counts)', () => {
+    expect(
+      summarizationTriggerSchema.safeParse({ type: 'remaining_tokens', value: 2000 }).success,
+    ).toBe(true);
+    expect(
+      summarizationTriggerSchema.safeParse({ type: 'messages_to_refine', value: 20 }).success,
+    ).toBe(true);
+  });
+
+  it('rejects non-finite values (Infinity, NaN) for every trigger type', () => {
+    for (const type of ['token_ratio', 'remaining_tokens', 'messages_to_refine'] as const) {
+      expect(summarizationTriggerSchema.safeParse({ type, value: Infinity }).success).toBe(false);
+      expect(summarizationTriggerSchema.safeParse({ type, value: -Infinity }).success).toBe(false);
+      expect(summarizationTriggerSchema.safeParse({ type, value: NaN }).success).toBe(false);
+    }
+  });
+
+  it('requires integer values for count-based triggers', () => {
+    expect(
+      summarizationTriggerSchema.safeParse({ type: 'remaining_tokens', value: 500.5 }).success,
+    ).toBe(false);
+    expect(
+      summarizationTriggerSchema.safeParse({ type: 'messages_to_refine', value: 2.5 }).success,
+    ).toBe(false);
+  });
+
+  it('still allows fractional values for token_ratio', () => {
+    expect(summarizationTriggerSchema.safeParse({ type: 'token_ratio', value: 0.8 }).success).toBe(
+      true,
+    );
+  });
+
+  it('parses inside the full summarization config', () => {
+    const result = summarizationConfigSchema.safeParse({
+      enabled: true,
+      trigger: { type: 'token_ratio', value: 0.8 },
+    });
+    expect(result.success).toBe(true);
+  });
+});
diff --git a/packages/data-provider/src/config.ts b/packages/data-provider/src/config.ts
index c0f614decd9b..7203c8d89bbb 100644
--- a/packages/data-provider/src/config.ts
+++ b/packages/data-provider/src/config.ts
@@ -1020,10 +1020,20 @@ export const memorySchema = z.object({
 
 export type TMemoryConfig = DeepPartial<z.infer<typeof memorySchema>>;
 
-export const summarizationTriggerSchema = z.object({
-  type: z.enum(['token_count']),
-  value: z.number().positive(),
-});
+export const summarizationTriggerSchema = z.discriminatedUnion('type', [
+  z.object({
+    type: z.literal('token_ratio'),
+    value: z.number().finite().min(0).max(1),
+  }),
+  z.object({
+    type: z.literal('remaining_tokens'),
+    value: z.number().finite().int().positive(),
+  }),
+  z.object({
+    type: z.literal('messages_to_refine'),
+    value: z.number().finite().int().positive(),
+  }),
+]);
 
 export const contextPruningSchema = z.object({
   enabled: z.boolean().optional(),
diff --git a/packages/data-schemas/src/app/service.spec.ts b/packages/data-schemas/src/app/service.spec.ts
new file mode 100644
index 000000000000..80298b3e1821
--- /dev/null
+++ b/packages/data-schemas/src/app/service.spec.ts
@@ -0,0 +1,80 @@
+import type { DeepPartial, TCustomConfig } from 'librechat-data-provider';
+import { loadSummarizationConfig } from './service';
+import logger from '~/config/winston';
+
+jest.mock('~/config/winston', () => ({
+  __esModule: true,
+  default: {
+    warn: jest.fn(),
+    info: jest.fn(),
+    error: jest.fn(),
+    debug: jest.fn(),
+  },
+}));
+
+describe('loadSummarizationConfig', () => {
+  const warnSpy = logger.warn as jest.Mock;
+
+  beforeEach(() => {
+    warnSpy.mockClear();
+  });
+
+  it('returns undefined when no summarization config is provided', () => {
+    expect(loadSummarizationConfig({} as DeepPartial<TCustomConfig>)).toBeUndefined();
+  });
+
+  it('accepts a valid token_ratio trigger', () => {
+    const result = loadSummarizationConfig({
+      summarization: {
+        enabled: true,
+        trigger: { type: 'token_ratio', value: 0.8 },
+      },
+    } as DeepPartial<TCustomConfig>);
+
+    expect(result).toBeDefined();
+    expect(result?.enabled).toBe(true);
+    expect(result?.trigger).toEqual({ type: 'token_ratio', value: 0.8 });
+    expect(warnSpy).not.toHaveBeenCalled();
+  });
+
+  it('emits a targeted migration warning when trigger.type is the legacy "token_count"', () => {
+    const result = loadSummarizationConfig({
+      summarization: {
+        trigger: { type: 'token_count', value: 8000 },
+      },
+    } as unknown as DeepPartial<TCustomConfig>);
+
+    expect(result).toBeUndefined();
+    expect(warnSpy).toHaveBeenCalledTimes(1);
+    const message = String(warnSpy.mock.calls[0][0]);
+    expect(message).toContain('token_count');
+    expect(message).toContain('token_ratio');
+    expect(message).toContain('remaining_tokens');
+    expect(message).toContain('messages_to_refine');
+    expect(message).toContain('fall back');
+  });
+
+  it('falls back to the generic warning when trigger is a bare string (not an object)', () => {
+    const result = loadSummarizationConfig({
+      summarization: {
+        trigger: 'token_count',
+      },
+    } as unknown as DeepPartial<TCustomConfig>);
+
+    expect(result).toBeUndefined();
+    expect(warnSpy).toHaveBeenCalledTimes(1);
+    expect(String(warnSpy.mock.calls[0][0])).toContain('Invalid summarization config');
+  });
+
+  it('falls back to the generic warning for other schema violations', () => {
+    const result = loadSummarizationConfig({
+      summarization: {
+        trigger: { type: 'token_ratio', value: 80 },
+      },
+    } as unknown as DeepPartial<TCustomConfig>);
+
+    expect(result).toBeUndefined();
+    expect(warnSpy).toHaveBeenCalledTimes(1);
+    expect(String(warnSpy.mock.calls[0][0])).toContain('Invalid summarization config');
+  });
+});
diff --git a/packages/data-schemas/src/app/service.ts b/packages/data-schemas/src/app/service.ts
index 91407b06c40d..57a5e603ac34 100644
--- a/packages/data-schemas/src/app/service.ts
+++ b/packages/data-schemas/src/app/service.ts
@@ -15,12 +15,30 @@ import { loadEndpoints } from './endpoints';
 import { loadOCRConfig } from './ocr';
 import logger from '~/config/winston';
 
-function loadSummarizationConfig(config: DeepPartial<TCustomConfig>): AppConfig['summarization'] {
+export function loadSummarizationConfig(
+  config: DeepPartial<TCustomConfig>,
+): AppConfig['summarization'] {
   const raw = config.summarization;
   if (!raw || typeof raw !== 'object') {
     return undefined;
   }
 
+  if (
+    raw.trigger &&
+    typeof raw.trigger === 'object' &&
+    (raw.trigger as { type?: unknown }).type === 'token_count'
+  ) {
+    logger.warn(
+      "[AppService] `summarization.trigger.type: 'token_count'` is no longer supported. " +
+        "Use 'token_ratio' (0-1), 'remaining_tokens' (positive integer), or " +
+        "'messages_to_refine' (positive integer). Your `summarization` config will be " +
+        'ignored and summarization will fall back to self-summarize defaults (the ' +
+        "agent's own provider/model, fires on every pruning event) until this is " +
+        'corrected.',
+    );
+    return undefined;
+  }
+
   const parsed = summarizationConfigSchema.safeParse(raw);
   if (!parsed.success) {
     logger.warn('[AppService] Invalid summarization config', parsed.error.flatten());