feat: add per-DM history limit overrides

src/agents/pi-embedded-runner.test.ts

@@ -431,6 +431,71 @@ describe("getDmHistoryLimitFromSessionKey", () => {
       ).toBe(5);
     }
   });
+
+  it("returns per-DM override when set", () => {
+    const config = {
+      telegram: {
+        dmHistoryLimit: 15,
+        dms: { "123": { historyLimit: 5 } },
+      },
+    } as ClawdbotConfig;
+    expect(getDmHistoryLimitFromSessionKey("telegram:dm:123", config)).toBe(5);
+  });
+
+  it("falls back to provider default when per-DM not set", () => {
+    const config = {
+      telegram: {
+        dmHistoryLimit: 15,
+        dms: { "456": { historyLimit: 5 } },
+      },
+    } as ClawdbotConfig;
+    expect(getDmHistoryLimitFromSessionKey("telegram:dm:123", config)).toBe(15);
+  });
+
+  it("returns per-DM override for agent-prefixed keys", () => {
+    const config = {
+      telegram: {
+        dmHistoryLimit: 20,
+        dms: { "789": { historyLimit: 3 } },
+      },
+    } as ClawdbotConfig;
+    expect(
+      getDmHistoryLimitFromSessionKey("agent:main:telegram:dm:789", config),
+    ).toBe(3);
+  });
+
+  it("handles userId with colons (e.g., email)", () => {
+    const config = {
+      msteams: {
+        dmHistoryLimit: 10,
+        dms: { "user@example.com": { historyLimit: 7 } },
+      },
+    } as ClawdbotConfig;
+    expect(
+      getDmHistoryLimitFromSessionKey("msteams:dm:user@example.com", config),
+    ).toBe(7);
+  });
+
+  it("returns undefined when per-DM historyLimit is not set", () => {
+    const config = {
+      telegram: {
+        dms: { "123": {} },
+      },
+    } as ClawdbotConfig;
+    expect(
+      getDmHistoryLimitFromSessionKey("telegram:dm:123", config),
+    ).toBeUndefined();
+  });
+
+  it("returns 0 when per-DM historyLimit is explicitly 0 (unlimited)", () => {
+    const config = {
+      telegram: {
+        dmHistoryLimit: 15,
+        dms: { "123": { historyLimit: 0 } },
+      },
+    } as ClawdbotConfig;
+    expect(getDmHistoryLimitFromSessionKey("telegram:dm:123", config)).toBe(0);
+  });
 });
 
 describe("runEmbeddedPiAgent", () => {

src/agents/pi-embedded-runner.ts

@@ -446,12 +446,16 @@ export function limitHistoryTurns(
 }
 
 /**
- * Extracts the provider name from a session key and looks up dmHistoryLimit
- * from the provider config.
+ * Extracts the provider name and user ID from a session key and looks up
+ * dmHistoryLimit from the provider config, with per-DM override support.
  *
  * Session key formats:
- * - `telegram:dm:123` → provider = telegram
- * - `agent:main:telegram:dm:123` → provider = telegram (skip "agent:<id>:")
+ * - `telegram:dm:123` → provider = telegram, userId = 123
+ * - `agent:main:telegram:dm:123` → provider = telegram, userId = 123
+ *
+ * Resolution order:
+ * 1. Per-DM override: provider.dms[userId].historyLimit
+ * 2. Provider default: provider.dmHistoryLimit
  */
 export function getDmHistoryLimitFromSessionKey(
   sessionKey: string | undefined,
@@ -467,22 +471,49 @@ export function getDmHistoryLimitFromSessionKey(
   const provider = providerParts[0]?.toLowerCase();
   if (!provider) return undefined;
 
+  // Extract userId: format is provider:dm:userId or provider:dm:userId:...
+  // The userId may contain colons (e.g., email addresses), so join remaining parts
+  const kind = providerParts[1]?.toLowerCase();
+  const userId = providerParts.slice(2).join(":");
+
+  // Helper to get limit with per-DM override support
+  const getLimit = (
+    providerConfig:
+      | {
+          dmHistoryLimit?: number;
+          dms?: Record<string, { historyLimit?: number }>;
+        }
+      | undefined,
+  ): number | undefined => {
+    if (!providerConfig) return undefined;
+    // Check per-DM override first
+    if (
+      userId &&
+      kind === "dm" &&
+      providerConfig.dms?.[userId]?.historyLimit !== undefined
+    ) {
+      return providerConfig.dms[userId].historyLimit;
+    }
+    // Fall back to provider default
+    return providerConfig.dmHistoryLimit;
+  };
+
   // Map provider to config key
   switch (provider) {
     case "telegram":
-      return config.telegram?.dmHistoryLimit;
+      return getLimit(config.telegram);
     case "whatsapp":
-      return config.whatsapp?.dmHistoryLimit;
+      return getLimit(config.whatsapp);
     case "discord":
-      return config.discord?.dmHistoryLimit;
+      return getLimit(config.discord);
     case "slack":
-      return config.slack?.dmHistoryLimit;
+      return getLimit(config.slack);
     case "signal":
-      return config.signal?.dmHistoryLimit;
+      return getLimit(config.signal);
     case "imessage":
-      return config.imessage?.dmHistoryLimit;
+      return getLimit(config.imessage);
     case "msteams":
-      return config.msteams?.dmHistoryLimit;
+      return getLimit(config.msteams);
     default:
       return undefined;
   }