refactor: simplify Telegram preview streaming to single boolean (#22012)

Merged via /review-pr -> /prepare-pr -> /merge-pr.

Prepared head SHA: a4017d3b94
Co-authored-by: obviyus <22031114+obviyus@users.noreply.github.com>
Co-authored-by: obviyus <22031114+obviyus@users.noreply.github.com>
Reviewed-by: @obviyus

CHANGELOG.md

@@ -24,6 +24,7 @@ Docs: https://docs.openclaw.ai
 - Security/Unused Dependencies: remove unused plugin-local `openclaw` devDependencies from `extensions/open-prose`, `extensions/lobster`, and `extensions/llm-task` after removing this dependency from build-time requirements. (#22495) Thanks @vincentkoc.
 - Agents/Subagents: default subagent spawn depth now uses shared `maxSpawnDepth=2`, enabling depth-1 orchestrator spawning by default while keeping depth policy checks consistent across spawn and prompt paths. (#22223) Thanks @tyler6204.
 - Channels/CLI: add per-account/channel `defaultTo` outbound routing fallback so `openclaw agent --deliver` can send without explicit `--reply-to` when a default target is configured. (#16985) Thanks @KirillShchetinin.
+- Telegram/Streaming: simplify preview streaming config to `channels.telegram.streaming` (boolean), auto-map legacy `streamMode` values, and remove block-vs-partial preview branching. (#22012) thanks @obviyus.
 - iOS/Chat: clean chat UI noise by stripping inbound untrusted metadata/timestamp prefixes, formatting tool outputs into concise summaries/errors, compacting the composer while typing, and supporting tap-to-dismiss keyboard in chat view. (#22122) thanks @mbelinky.
 - iOS/Watch: bridge mirrored watch prompt notification actions into iOS quick-reply handling, including queued action handoff until app model initialization. (#22123) thanks @mbelinky.
 - iOS/Tests: cover IPv4-mapped IPv6 loopback in manual TLS policy tests for connect validation paths. (#22045) Thanks @mbelinky.

docs/channels/grammy.md

@@ -21,7 +21,7 @@ title: grammY
 - **Webhook support:** `webhook-set.ts` wraps `setWebhook/deleteWebhook`; `webhook.ts` hosts the callback with health + graceful shutdown. Gateway enables webhook mode when `channels.telegram.webhookUrl` + `channels.telegram.webhookSecret` are set (otherwise it long-polls).
 - **Sessions:** direct chats collapse into the agent main session (`agent:<agentId>:<mainKey>`); groups use `agent:<agentId>:telegram:group:<chatId>`; replies route back to the same channel.
 - **Config knobs:** `channels.telegram.botToken`, `channels.telegram.dmPolicy`, `channels.telegram.groups` (allowlist + mention defaults), `channels.telegram.allowFrom`, `channels.telegram.groupAllowFrom`, `channels.telegram.groupPolicy`, `channels.telegram.mediaMaxMb`, `channels.telegram.linkPreview`, `channels.telegram.proxy`, `channels.telegram.webhookSecret`, `channels.telegram.webhookUrl`, `channels.telegram.webhookHost`.
-- **Live stream preview:** optional `channels.telegram.streamMode` sends a temporary message and updates it with `editMessageText`. This is separate from channel block streaming.
+- **Live stream preview:** optional `channels.telegram.streaming` sends a temporary message and updates it with `editMessageText`. This is separate from channel block streaming.
 - **Tests:** grammy mocks cover DM + group mention gating and outbound send; more media/webhook fixtures still welcome.
 
 Open questions

docs/channels/telegram.md

@@ -226,21 +226,8 @@ curl "https://api.telegram.org/bot<bot_token>/getUpdates"
 
     Requirement:
 
-    - `channels.telegram.streamMode` is not `"off"` (default: `"partial"`)
-
-    Modes:
-
-    - `off`: no live preview
-    - `partial`: frequent preview updates from partial text
-    - `block`: chunked preview updates using `channels.telegram.draftChunk`
-
-    `draftChunk` defaults for `streamMode: "block"`:
-
-    - `minChars: 200`
-    - `maxChars: 800`
-    - `breakPreference: "paragraph"`
-
-    `maxChars` is clamped by `channels.telegram.textChunkLimit`.
+    - `channels.telegram.streaming` is `true` (default)
+    - legacy `channels.telegram.streamMode` values are auto-mapped to `streaming`
 
     This works in direct chats and groups/topics.
 
@@ -248,7 +235,7 @@ curl "https://api.telegram.org/bot<bot_token>/getUpdates"
 
     For complex replies (for example media payloads), OpenClaw falls back to normal final delivery and then cleans up the preview message.
 
-    `streamMode` is separate from block streaming. When block streaming is explicitly enabled for Telegram, OpenClaw skips the preview stream to avoid double-streaming.
+    Preview streaming is separate from block streaming. When block streaming is explicitly enabled for Telegram, OpenClaw skips the preview stream to avoid double-streaming.
 
     Telegram-only reasoning stream:
 
@@ -721,7 +708,7 @@ Primary reference:
 - `channels.telegram.textChunkLimit`: outbound chunk size (chars).
 - `channels.telegram.chunkMode`: `length` (default) or `newline` to split on blank lines (paragraph boundaries) before length chunking.
 - `channels.telegram.linkPreview`: toggle link previews for outbound messages (default: true).
-- `channels.telegram.streamMode`: `off | partial | block` (live stream preview).
+- `channels.telegram.streaming`: `true | false` (live stream preview; default: true).
 - `channels.telegram.mediaMaxMb`: inbound/outbound media cap (MB).
 - `channels.telegram.retry`: retry policy for outbound Telegram API calls (attempts, minDelayMs, maxDelayMs, jitter).
 - `channels.telegram.network.autoSelectFamily`: override Node autoSelectFamily (true=enable, false=disable). Defaults to disabled on Node 22 to avoid Happy Eyeballs timeouts.
@@ -745,7 +732,7 @@ Telegram-specific high-signal fields:
 - access control: `dmPolicy`, `allowFrom`, `groupPolicy`, `groupAllowFrom`, `groups`, `groups.*.topics.*`
 - command/menu: `commands.native`, `customCommands`
 - threading/replies: `replyToMode`
-- streaming: `streamMode` (preview), `draftChunk`, `blockStreaming`
+- streaming: `streaming` (preview), `blockStreaming`
 - formatting/delivery: `textChunkLimit`, `chunkMode`, `linkPreview`, `responsePrefix`
 - media/network: `mediaMaxMb`, `timeoutSeconds`, `retry`, `network.autoSelectFamily`, `proxy`
 - webhook: `webhookUrl`, `webhookSecret`, `webhookPath`, `webhookHost`

docs/concepts/streaming.md

@@ -100,7 +100,7 @@ This maps to:
 
 **Channel note:** For non-Telegram channels, block streaming is **off unless**
 `*.blockStreaming` is explicitly set to `true`. Telegram can stream a live preview
-(`channels.telegram.streamMode`) without block replies.
+(`channels.telegram.streaming`) without block replies.
 
 Config location reminder: the `blockStreaming*` defaults live under
 `agents.defaults`, not the root config.
@@ -110,11 +110,7 @@ Config location reminder: the `blockStreaming*` defaults live under
 Telegram is the only channel with live preview streaming:
 
 - Uses Bot API `sendMessage` (first update) + `editMessageText` (subsequent updates).
-- `channels.telegram.streamMode: "partial" | "block" | "off"`.
-  - `partial`: preview updates with latest stream text.
-  - `block`: preview updates in chunked blocks (same chunker rules).
-  - `off`: no preview streaming.
-- Preview chunk config (only for `streamMode: "block"`): `channels.telegram.draftChunk` (defaults: `minChars: 200`, `maxChars: 800`).
+- `channels.telegram.streaming: true | false` (default: `true`).
 - Preview streaming is separate from block streaming.
 - When Telegram block streaming is explicitly enabled, preview streaming is skipped to avoid double-streaming.
 - Text-only finals are applied by editing the preview message in place.
@@ -124,8 +120,7 @@ Telegram is the only channel with live preview streaming:
 ```
 Telegram
   └─ sendMessage (temporary preview message)
-       ├─ streamMode=partial → edit latest text
-       └─ streamMode=block   → chunker + edit updates
+       └─ streaming=true → edit latest text
   └─ final text-only reply → final edit on same message
   └─ fallback: cleanup preview + normal final delivery (media/complex)
 ```

docs/gateway/configuration-reference.md

@@ -151,12 +151,7 @@ WhatsApp runs through the gateway's web channel (Baileys Web). It starts automat
       historyLimit: 50,
       replyToMode: "first", // off | first | all
       linkPreview: true,
-      streamMode: "partial", // off | partial | block
-      draftChunk: {
-        minChars: 200,
-        maxChars: 800,
-        breakPreference: "paragraph", // paragraph | newline | sentence
-      },
+      streaming: true, // live preview on/off (default true)
       actions: { reactions: true, sendMessage: true },
       reactionNotifications: "own", // off | own | all
       mediaMaxMb: 5,

src/config/config.legacy-config-detection.rejects-routing-allowfrom.e2e.test.ts

@@ -378,11 +378,46 @@ describe("legacy config detection", () => {
       expect(res.config.channels?.telegram?.groupPolicy).toBe("allowlist");
     }
   });
-  it("defaults telegram.streamMode to partial when telegram section exists", async () => {
+  it("defaults telegram.streaming to true when telegram section exists", async () => {
     const res = validateConfigObject({ channels: { telegram: {} } });
     expect(res.ok).toBe(true);
     if (res.ok) {
-      expect(res.config.channels?.telegram?.streamMode).toBe("partial");
+      expect(res.config.channels?.telegram?.streaming).toBe(true);
+      expect(res.config.channels?.telegram?.streamMode).toBeUndefined();
+    }
+  });
+  it("migrates legacy telegram.streamMode=off to streaming=false", async () => {
+    const res = validateConfigObject({ channels: { telegram: { streamMode: "off" } } });
+    expect(res.ok).toBe(true);
+    if (res.ok) {
+      expect(res.config.channels?.telegram?.streaming).toBe(false);
+      expect(res.config.channels?.telegram?.streamMode).toBeUndefined();
+    }
+  });
+  it("migrates legacy telegram.streamMode=block to streaming=true", async () => {
+    const res = validateConfigObject({ channels: { telegram: { streamMode: "block" } } });
+    expect(res.ok).toBe(true);
+    if (res.ok) {
+      expect(res.config.channels?.telegram?.streaming).toBe(true);
+      expect(res.config.channels?.telegram?.streamMode).toBeUndefined();
+    }
+  });
+  it("migrates legacy telegram.accounts.*.streamMode to streaming", async () => {
+    const res = validateConfigObject({
+      channels: {
+        telegram: {
+          accounts: {
+            ops: {
+              streamMode: "off",
+            },
+          },
+        },
+      },
+    });
+    expect(res.ok).toBe(true);
+    if (res.ok) {
+      expect(res.config.channels?.telegram?.accounts?.ops?.streaming).toBe(false);
+      expect(res.config.channels?.telegram?.accounts?.ops?.streamMode).toBeUndefined();
     }
   });
   it('rejects whatsapp.dmPolicy="open" without allowFrom "*"', async () => {

src/config/schema.help.ts

@@ -391,14 +391,8 @@ export const FIELD_HELP: Record<string, string> = {
     "Debounce window (ms) for batching rapid inbound messages from the same sender (0 to disable).",
   "channels.telegram.dmPolicy":
     'Direct message access control ("pairing" recommended). "open" requires channels.telegram.allowFrom=["*"].',
-  "channels.telegram.streamMode":
-    "Live stream preview mode for Telegram replies (off | partial | block). Separate from block streaming; uses sendMessage + editMessageText.",
-  "channels.telegram.draftChunk.minChars":
-    'Minimum chars before emitting a Telegram stream preview update when channels.telegram.streamMode="block" (default: 200).',
-  "channels.telegram.draftChunk.maxChars":
-    'Target max size for a Telegram stream preview chunk when channels.telegram.streamMode="block" (default: 800; clamped to channels.telegram.textChunkLimit).',
-  "channels.telegram.draftChunk.breakPreference":
-    "Preferred breakpoints for Telegram draft chunks (paragraph | newline | sentence). Default: paragraph.",
+  "channels.telegram.streaming":
+    "Enable Telegram live stream preview via message edits (default: true; legacy streamMode auto-maps here).",
   "channels.discord.streamMode":
     "Live stream preview mode for Discord replies (off | partial | block). Separate from block streaming; uses sendMessage + editMessage.",
   "channels.discord.draftChunk.minChars":

src/config/schema.labels.ts

@@ -263,10 +263,7 @@ export const FIELD_LABELS: Record<string, string> = {
   ...IRC_FIELD_LABELS,
   "channels.telegram.botToken": "Telegram Bot Token",
   "channels.telegram.dmPolicy": "Telegram DM Policy",
-  "channels.telegram.streamMode": "Telegram Stream Mode",
-  "channels.telegram.draftChunk.minChars": "Telegram Draft Chunk Min Chars",
-  "channels.telegram.draftChunk.maxChars": "Telegram Draft Chunk Max Chars",
-  "channels.telegram.draftChunk.breakPreference": "Telegram Draft Chunk Break Preference",
+  "channels.telegram.streaming": "Telegram Streaming",
   "channels.telegram.retry.attempts": "Telegram Retry Attempts",
   "channels.telegram.retry.minDelayMs": "Telegram Retry Min Delay (ms)",
   "channels.telegram.retry.maxDelayMs": "Telegram Retry Max Delay (ms)",

src/config/types.telegram.ts

@@ -95,13 +95,15 @@ export type TelegramAccountConfig = {
   textChunkLimit?: number;
   /** Chunking mode: "length" (default) splits by size; "newline" splits on every newline. */
   chunkMode?: "length" | "newline";
+  /** Enable live stream preview via message edits (default: true). */
+  streaming?: boolean;
   /** Disable block streaming for this account. */
   blockStreaming?: boolean;
-  /** Chunking config for Telegram stream previews in `streamMode: "block"`. */
+  /** @deprecated Legacy chunking config from `streamMode: "block"`; ignored after migration. */
   draftChunk?: BlockStreamingChunkConfig;
   /** Merge streamed block replies before sending. */
   blockStreamingCoalesce?: BlockStreamingCoalesceConfig;
-  /** Telegram stream preview mode (off|partial|block). Default: partial. */
+  /** @deprecated Legacy key; migrated automatically to `streaming` boolean. */
   streamMode?: "off" | "partial" | "block";
   mediaMaxMb?: number;
   /** Telegram API client timeout in seconds (grammY ApiClientOptions). */

src/config/zod-schema.providers-core.ts

@@ -99,6 +99,27 @@ const validateTelegramCustomCommands = (
   }
 };
 
+function normalizeTelegramStreamingConfig(value: {
+  streaming?: boolean;
+  streamMode?: "off" | "partial" | "block";
+}) {
+  if (typeof value.streaming === "boolean") {
+    delete value.streamMode;
+    return;
+  }
+  if (value.streamMode === "off") {
+    value.streaming = false;
+    delete value.streamMode;
+    return;
+  }
+  if (value.streamMode === "partial" || value.streamMode === "block") {
+    value.streaming = true;
+    delete value.streamMode;
+    return;
+  }
+  value.streaming = true;
+}
+
 export const TelegramAccountSchemaBase = z
   .object({
     name: z.string().optional(),
@@ -122,10 +143,12 @@ export const TelegramAccountSchemaBase = z
     dms: z.record(z.string(), DmConfigSchema.optional()).optional(),
     textChunkLimit: z.number().int().positive().optional(),
     chunkMode: z.enum(["length", "newline"]).optional(),
+    streaming: z.boolean().optional(),
     blockStreaming: z.boolean().optional(),
     draftChunk: BlockStreamingChunkSchema.optional(),
     blockStreamingCoalesce: BlockStreamingCoalesceSchema.optional(),
-    streamMode: z.enum(["off", "partial", "block"]).optional().default("partial"),
+    // Legacy key kept for automatic migration to `streaming`.
+    streamMode: z.enum(["off", "partial", "block"]).optional(),
     mediaMaxMb: z.number().positive().optional(),
     timeoutSeconds: z.number().int().positive().optional(),
     retry: RetryConfigSchema,
@@ -159,6 +182,7 @@ export const TelegramAccountSchemaBase = z
   .strict();
 
 export const TelegramAccountSchema = TelegramAccountSchemaBase.superRefine((value, ctx) => {
+  normalizeTelegramStreamingConfig(value);
   requireOpenAllowFrom({
     policy: value.dmPolicy,
     allowFrom: value.allowFrom,
@@ -173,6 +197,7 @@ export const TelegramAccountSchema = TelegramAccountSchemaBase.superRefine((valu
 export const TelegramConfigSchema = TelegramAccountSchemaBase.extend({
   accounts: z.record(z.string(), TelegramAccountSchema.optional()).optional(),
 }).superRefine((value, ctx) => {
+  normalizeTelegramStreamingConfig(value);
   requireOpenAllowFrom({
     policy: value.dmPolicy,
     allowFrom: value.allowFrom,

src/telegram/bot-message-dispatch.test.ts

@@ -193,7 +193,7 @@ describe("dispatchTelegramMessage draft streaming", () => {
     expect(draftStream.clear).toHaveBeenCalledTimes(1);
   });
 
-  it("keeps a higher initial debounce threshold in block stream mode", async () => {
+  it("uses immediate preview updates for legacy block stream mode", async () => {
     const draftStream = createDraftStream();
     createTelegramDraftStream.mockReturnValue(draftStream);
     dispatchReplyWithBufferedBlockDispatcher.mockImplementation(
@@ -209,7 +209,7 @@ describe("dispatchTelegramMessage draft streaming", () => {
 
     expect(createTelegramDraftStream).toHaveBeenCalledWith(
       expect.objectContaining({
-        minInitialChars: 30,
+        minInitialChars: 1,
       }),
     );
   });
@@ -445,7 +445,7 @@ describe("dispatchTelegramMessage draft streaming", () => {
     );
   });
 
-  it("forces new message when new assistant message starts after previous output", async () => {
+  it("does not force new message for legacy block stream mode", async () => {
     const draftStream = createDraftStream(999);
     createTelegramDraftStream.mockReturnValue(draftStream);
     dispatchReplyWithBufferedBlockDispatcher.mockImplementation(
@@ -464,8 +464,7 @@ describe("dispatchTelegramMessage draft streaming", () => {
 
     await dispatchWithContext({ context: createContext(), streamMode: "block" });
 
-    // Should force new message when assistant message starts after previous output
-    expect(draftStream.forceNewMessage).toHaveBeenCalled();
+    expect(draftStream.forceNewMessage).not.toHaveBeenCalled();
   });
 
   it("does not force new message in partial mode when assistant message restarts", async () => {

src/telegram/bot-message-dispatch.ts

@@ -6,7 +6,6 @@ import {
   modelSupportsVision,
 } from "../agents/model-catalog.js";
 import { resolveDefaultModelForAgent } from "../agents/model-selection.js";
-import { EmbeddedBlockChunker } from "../agents/pi-embedded-block-chunker.js";
 import { resolveChunkMode } from "../auto-reply/chunk.js";
 import { clearHistoryEntriesIfEnabled } from "../auto-reply/reply/history.js";
 import { dispatchReplyWithBufferedBlockDispatcher } from "../auto-reply/reply/provider-dispatcher.js";
@@ -26,7 +25,6 @@ import type { TelegramBotOptions } from "./bot.js";
 import { deliverReplies } from "./bot/delivery.js";
 import type { TelegramStreamMode } from "./bot/types.js";
 import type { TelegramInlineButtons } from "./button-types.js";
-import { resolveTelegramDraftStreamingChunking } from "./draft-chunking.js";
 import { createTelegramDraftStream } from "./draft-stream.js";
 import { renderTelegramHtmlText } from "./format.js";
 import {
@@ -143,21 +141,20 @@ export const dispatchTelegramMessage = async ({
   });
   const forceBlockStreamingForReasoning = resolvedReasoningLevel === "on";
   const streamReasoningDraft = resolvedReasoningLevel === "stream";
+  const previewStreamingEnabled = streamMode !== "off";
   const canStreamAnswerDraft =
-    streamMode !== "off" && !accountBlockStreamingEnabled && !forceBlockStreamingForReasoning;
+    previewStreamingEnabled && !accountBlockStreamingEnabled && !forceBlockStreamingForReasoning;
   const canStreamReasoningDraft = canStreamAnswerDraft || streamReasoningDraft;
   const draftReplyToMessageId =
     replyToMode !== "off" && typeof msg.message_id === "number" ? msg.message_id : undefined;
   const draftMinInitialChars =
-    streamMode === "partial" || streamReasoningDraft ? 1 : DRAFT_MIN_INITIAL_CHARS;
+    previewStreamingEnabled || streamReasoningDraft ? 1 : DRAFT_MIN_INITIAL_CHARS;
   const mediaLocalRoots = getAgentScopedMediaLocalRoots(cfg, route.agentId);
   type LaneName = "answer" | "reasoning";
   type DraftLaneState = {
     stream: ReturnType<typeof createTelegramDraftStream> | undefined;
     lastPartialText: string;
-    draftText: string;
     hasStreamedMessage: boolean;
-    chunker: EmbeddedBlockChunker | undefined;
   };
   const createDraftLane = (enabled: boolean): DraftLaneState => {
     const stream = enabled
@@ -173,16 +170,10 @@ export const dispatchTelegramMessage = async ({
           warn: logVerbose,
         })
       : undefined;
-    const chunker =
-      stream && streamMode === "block"
-        ? new EmbeddedBlockChunker(resolveTelegramDraftStreamingChunking(cfg, route.accountId))
-        : undefined;
     return {
       stream,
       lastPartialText: "",
-      draftText: "",
       hasStreamedMessage: false,
-      chunker,
     };
   };
   const lanes: Record<LaneName, DraftLaneState> = {
@@ -207,9 +198,7 @@ export const dispatchTelegramMessage = async ({
   };
   const resetDraftLaneState = (lane: DraftLaneState) => {
     lane.lastPartialText = "";
-    lane.draftText = "";
     lane.hasStreamedMessage = false;
-    lane.chunker?.reset();
   };
   const updateDraftFromPartial = (lane: DraftLaneState, text: string | undefined) => {
     const laneStream = lane.stream;
@@ -221,46 +210,18 @@ export const dispatchTelegramMessage = async ({
     }
     // Mark that we've received streaming content (for forceNewMessage decision).
     lane.hasStreamedMessage = true;
-    if (streamMode === "partial") {
-      // Some providers briefly emit a shorter prefix snapshot (for example
-      // "Sure." -> "Sure" -> "Sure."). Keep the longer preview to avoid
-      // visible punctuation flicker.
-      if (
-        lane.lastPartialText &&
-        lane.lastPartialText.startsWith(text) &&
-        text.length < lane.lastPartialText.length
-      ) {
-        return;
-      }
-      lane.lastPartialText = text;
-      laneStream.update(text);
+    // Some providers briefly emit a shorter prefix snapshot (for example
+    // "Sure." -> "Sure" -> "Sure."). Keep the longer preview to avoid
+    // visible punctuation flicker.
+    if (
+      lane.lastPartialText &&
+      lane.lastPartialText.startsWith(text) &&
+      text.length < lane.lastPartialText.length
+    ) {
       return;
     }
-    let delta = text;
-    if (text.startsWith(lane.lastPartialText)) {
-      delta = text.slice(lane.lastPartialText.length);
-    } else {
-      // Streaming buffer reset (or non-monotonic stream). Start fresh.
-      lane.chunker?.reset();
-      lane.draftText = "";
-    }
     lane.lastPartialText = text;
-    if (!delta) {
-      return;
-    }
-    if (!lane.chunker) {
-      lane.draftText = text;
-      laneStream.update(lane.draftText);
-      return;
-    }
-    lane.chunker.append(delta);
-    lane.chunker.drain({
-      force: false,
-      emit: (chunk) => {
-        lane.draftText += chunk;
-        laneStream.update(lane.draftText);
-      },
-    });
+    laneStream.update(text);
   };
   const ingestDraftLaneSegments = (text: string | undefined) => {
     for (const segment of splitTextIntoLaneSegments(text)) {
@@ -275,31 +236,18 @@ export const dispatchTelegramMessage = async ({
     if (!lane.stream) {
       return;
     }
-    if (lane.chunker?.hasBuffered()) {
-      lane.chunker.drain({
-        force: true,
-        emit: (chunk) => {
-          lane.draftText += chunk;
-        },
-      });
-      lane.chunker.reset();
-      if (lane.draftText) {
-        lane.stream.update(lane.draftText);
-      }
-    }
     await lane.stream.flush();
   };
 
-  const disableBlockStreaming =
-    streamMode === "off"
-      ? true
-      : forceBlockStreamingForReasoning
-        ? false
-        : typeof telegramCfg.blockStreaming === "boolean"
-          ? !telegramCfg.blockStreaming
-          : canStreamAnswerDraft
-            ? true
-            : undefined;
+  const disableBlockStreaming = !previewStreamingEnabled
+    ? true
+    : forceBlockStreamingForReasoning
+      ? false
+      : typeof telegramCfg.blockStreaming === "boolean"
+        ? !telegramCfg.blockStreaming
+        : canStreamAnswerDraft
+          ? true
+          : undefined;
 
   const { onModelSelected, ...prefixOptions } = createReplyPrefixOptions({
     cfg,
@@ -395,8 +343,7 @@ export const dispatchTelegramMessage = async ({
     linkPreview: telegramCfg.linkPreview,
     replyQuoteText,
   };
-  const getLanePreviewText = (lane: DraftLaneState) =>
-    streamMode === "block" ? lane.draftText : lane.lastPartialText;
+  const getLanePreviewText = (lane: DraftLaneState) => lane.lastPartialText;
   const tryUpdatePreviewForLane = async (params: {
     lane: DraftLaneState;
     laneName: LaneName;
@@ -449,7 +396,6 @@ export const dispatchTelegramMessage = async ({
       });
       if (updateLaneSnapshot) {
         lane.lastPartialText = text;
-        lane.draftText = text;
       }
       deliveryState.delivered = true;
       return true;
@@ -684,10 +630,6 @@ export const dispatchTelegramMessage = async ({
         onAssistantMessageStart: answerLane.stream
           ? () => {
               reasoningStepState.resetForNextStep();
-              // Keep answer blocks separated in block mode; partial mode keeps one answer lane.
-              if (streamMode === "block" && answerLane.hasStreamedMessage) {
-                answerLane.stream?.forceNewMessage();
-              }
               resetDraftLaneState(answerLane);
             }
           : undefined,

src/telegram/bot/helpers.ts

@@ -154,11 +154,18 @@ export function buildTypingThreadParams(messageThreadId?: number) {
 }
 
 export function resolveTelegramStreamMode(telegramCfg?: {
+  streaming?: boolean;
   streamMode?: TelegramStreamMode;
 }): TelegramStreamMode {
+  if (typeof telegramCfg?.streaming === "boolean") {
+    return telegramCfg.streaming ? "partial" : "off";
+  }
   const raw = telegramCfg?.streamMode?.trim().toLowerCase();
-  if (raw === "off" || raw === "partial" || raw === "block") {
-    return raw;
+  if (raw === "off") {
+    return "off";
+  }
+  if (raw === "partial" || raw === "block") {
+    return "partial";
   }
   return "partial";
 }