diff --git a/CHANGELOG.md b/CHANGELOG.md
index 9a32fba17..b9a550c5e 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -18,8 +18,8 @@ Docs: https://docs.clawd.bot
 - Docs: add Bedrock EC2 instance role setup + IAM steps. (#1625) Thanks @sergical. https://docs.clawd.bot/bedrock
 - Exec approvals: forward approval prompts to chat with `/approve` for all channels (including plugins). (#1621) Thanks @czekaj. https://docs.clawd.bot/tools/exec-approvals https://docs.clawd.bot/tools/slash-commands
 - Gateway: expose config.patch in the gateway tool with safe partial updates + restart sentinel. (#1653) Thanks @Glucksberg.
-- Telegram: treat DM topics as separate sessions and keep DM history limits stable with thread suffixes.
-- Telegram: add verbose raw-update logging for inbound Telegram updates.
+- Telegram: treat DM topics as separate sessions and keep DM history limits stable with thread suffixes. (#1597) Thanks @rohannagpal.
+- Telegram: add verbose raw-update logging for inbound Telegram updates. (#1597) Thanks @rohannagpal.
 
 ### Fixes
 - BlueBubbles: keep part-index GUIDs in reply tags when short IDs are missing.
@@ -41,9 +41,9 @@ Docs: https://docs.clawd.bot
 - Google Chat: tighten email allowlist matching, typing cleanup, media caps, and onboarding/docs/tests. (#1635) Thanks @iHildy.
 - Google Chat: normalize space targets without double `spaces/` prefix.
 - Messaging: keep newline chunking safe for fenced markdown blocks across channels.
-- Tests: cap Vitest workers on CI macOS to reduce timeouts.
-- Tests: avoid fake-timer dependency in embedded runner stream mock to reduce CI flakes.
-- Tests: increase embedded runner ordering test timeout to reduce CI flakes.
+- Tests: cap Vitest workers on CI macOS to reduce timeouts. (#1597) Thanks @rohannagpal.
+- Tests: avoid fake-timer dependency in embedded runner stream mock to reduce CI flakes. (#1597) Thanks @rohannagpal.
+- Tests: increase embedded runner ordering test timeout to reduce CI flakes. (#1597) Thanks @rohannagpal.
 
 ## 2026.1.23-1
 
diff --git a/src/agents/pi-embedded-runner.get-dm-history-limit-from-session-key.returns-undefined-sessionkey-is-undefined.test.ts b/src/agents/pi-embedded-runner.get-dm-history-limit-from-session-key.returns-undefined-sessionkey-is-undefined.test.ts
index ec2b58f79..8c3be721b 100644
--- a/src/agents/pi-embedded-runner.get-dm-history-limit-from-session-key.returns-undefined-sessionkey-is-undefined.test.ts
+++ b/src/agents/pi-embedded-runner.get-dm-history-limit-from-session-key.returns-undefined-sessionkey-is-undefined.test.ts
@@ -131,6 +131,16 @@ describe("getDmHistoryLimitFromSessionKey", () => {
     expect(getDmHistoryLimitFromSessionKey("agent:main:telegram:dm:123:topic:555", config)).toBe(7);
     expect(getDmHistoryLimitFromSessionKey("telegram:dm:123:thread:999", config)).toBe(7);
   });
+  it("keeps non-numeric thread markers in dm ids", () => {
+    const config = {
+      channels: {
+        telegram: { dms: { "user:thread:abc": { historyLimit: 9 } } },
+      },
+    } as ClawdbotConfig;
+    expect(getDmHistoryLimitFromSessionKey("agent:main:telegram:dm:user:thread:abc", config)).toBe(
+      9,
+    );
+  });
   it("returns undefined for non-dm session kinds", () => {
     const config = {
       channels: {
diff --git a/src/agents/pi-embedded-runner/history.ts b/src/agents/pi-embedded-runner/history.ts
index 37e3e0edf..91706222a 100644
--- a/src/agents/pi-embedded-runner/history.ts
+++ b/src/agents/pi-embedded-runner/history.ts
@@ -2,17 +2,11 @@ import type { AgentMessage } from "@mariozechner/pi-agent-core";
 
 import type { ClawdbotConfig } from "../../config/config.js";
 
-const THREAD_SUFFIX_MARKERS = [":thread:", ":topic:"];
+const THREAD_SUFFIX_REGEX = /^(.*)(?::(?:thread|topic):\d+)$/i;
 
 function stripThreadSuffix(value: string): string {
-  const lower = value.toLowerCase();
-  let idx = -1;
-  for (const marker of THREAD_SUFFIX_MARKERS) {
-    const pos = lower.lastIndexOf(marker);
-    if (pos > idx) idx = pos;
-  }
-  if (idx <= 0) return value;
-  return value.slice(0, idx);
+  const match = value.match(THREAD_SUFFIX_REGEX);
+  return match?.[1] ?? value;
 }
 
 /**
diff --git a/src/telegram/bot.ts b/src/telegram/bot.ts
index 652aaa4e7..d958d5616 100644
--- a/src/telegram/bot.ts
+++ b/src/telegram/bot.ts
@@ -164,12 +164,36 @@ export function createTelegramBot(opts: TelegramBotOptions) {
   };
 
   const rawUpdateLogger = createSubsystemLogger("gateway/channels/telegram/raw-update");
+  const MAX_RAW_UPDATE_CHARS = 8000;
+  const MAX_RAW_UPDATE_STRING = 500;
+  const MAX_RAW_UPDATE_ARRAY = 20;
+  const stringifyUpdate = (update: unknown) => {
+    const seen = new WeakSet<object>();
+    return JSON.stringify(update ?? null, (key, value) => {
+      if (typeof value === "string" && value.length > MAX_RAW_UPDATE_STRING) {
+        return `${value.slice(0, MAX_RAW_UPDATE_STRING)}...`;
+      }
+      if (Array.isArray(value) && value.length > MAX_RAW_UPDATE_ARRAY) {
+        return [
+          ...value.slice(0, MAX_RAW_UPDATE_ARRAY),
+          `...(${value.length - MAX_RAW_UPDATE_ARRAY} more)`,
+        ];
+      }
+      if (value && typeof value === "object") {
+        const obj = value as object;
+        if (seen.has(obj)) return "[Circular]";
+        seen.add(obj);
+      }
+      return value;
+    });
+  };
 
   bot.use(async (ctx, next) => {
     if (shouldLogVerbose()) {
       try {
-        const raw = JSON.stringify(ctx.update ?? null);
-        const preview = raw.length > 8000 ? raw.slice(0, 8000) + "…" : raw;
+        const raw = stringifyUpdate(ctx.update);
+        const preview =
+          raw.length > MAX_RAW_UPDATE_CHARS ? `${raw.slice(0, MAX_RAW_UPDATE_CHARS)}...` : raw;
         rawUpdateLogger.debug(`telegram update: ${preview}`);
       } catch (err) {
         rawUpdateLogger.debug(`telegram update log failed: ${String(err)}`);