fix(agents): keep continuation bootstrap marker across short reads (#108253)

* fix(agents): keep bootstrap markers across short reads

* refactor(infra): share bounded file window reads

Co-authored-by: sunlit-deng <yang.jiajun1@xydigit.com>

---------

Co-authored-by: Peter Steinberger <steipete@gmail.com>

src/agents/bootstrap-files.test.ts

@@ -3,7 +3,7 @@ import { randomUUID } from "node:crypto";
 import fs from "node:fs/promises";
 import path from "node:path";
 import { expectDefined } from "@openclaw/normalization-core";
-import { afterEach, beforeEach, describe, expect, it } from "vitest";
+import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
 import {
   clearInternalHooks,
   registerInternalHook,
@@ -495,6 +495,7 @@ describe("hasCompletedBootstrapTurn", () => {
   });
 
   afterEach(async () => {
+    vi.restoreAllMocks();
     await fs.rm(tmpDir, { recursive: true, force: true });
   });
 
@@ -640,6 +641,37 @@ describe("hasCompletedBootstrapTurn", () => {
     expect(await hasCompletedBootstrapTurn(sessionFile)).toBe(true);
   });
 
+  it("finds a recent full bootstrap marker when the tail read returns short", async () => {
+    const sessionFile = path.join(tmpDir, "short-read-tail.jsonl");
+    const lines = [
+      JSON.stringify({ type: "message", message: { role: "user", content: "hello" } }),
+      JSON.stringify({ type: "message", message: { role: "assistant", content: "hi" } }),
+      JSON.stringify({
+        type: "custom",
+        customType: FULL_BOOTSTRAP_COMPLETED_CUSTOM_TYPE,
+        data: { timestamp: 1 },
+      }),
+    ];
+    await fs.writeFile(sessionFile, `${lines.join("\n")}\n`, "utf8");
+
+    const realOpen = fs.open.bind(fs);
+    vi.spyOn(fs, "open").mockImplementation(async (...args) => {
+      const handle = await realOpen(...args);
+      const realRead = handle.read.bind(handle);
+      return new Proxy(handle, {
+        get(target, prop, receiver) {
+          if (prop === "read") {
+            return (buffer: Buffer, offset: number, length: number, position: number) =>
+              realRead(buffer, offset, Math.min(length, 16), position);
+          }
+          return Reflect.get(target, prop, receiver);
+        },
+      });
+    });
+
+    expect(await hasCompletedBootstrapTurn(sessionFile)).toBe(true);
+  });
+
   it("returns false for symbolic links", async () => {
     const realFile = path.join(tmpDir, "real.jsonl");
     const linkFile = path.join(tmpDir, "link.jsonl");

src/agents/bootstrap-files.ts

@@ -8,6 +8,7 @@ import { normalizeOptionalString } from "@openclaw/normalization-core/string-coe
 import { parseSqliteSessionFileMarker } from "../config/sessions/sqlite-marker.js";
 import type { AgentContextInjection } from "../config/types.agent-defaults.js";
 import type { OpenClawConfig } from "../config/types.openclaw.js";
+import { readFileWindowFully } from "../infra/file-read.js";
 import { resolveUserPath } from "../utils.js";
 import { resolveAgentConfig, resolveSessionAgentIds } from "./agent-scope.js";
 import { getOrLoadBootstrapFiles } from "./bootstrap-cache.js";
@@ -87,7 +88,7 @@ export async function hasCompletedBootstrapTurn(sessionFile: string): Promise<bo
       }
       const start = stat.size - bytesToRead;
       const buffer = Buffer.allocUnsafe(bytesToRead);
-      const { bytesRead } = await fh.read(buffer, 0, bytesToRead, start);
+      const bytesRead = await readFileWindowFully(fh, buffer, start);
       let text = buffer.toString("utf-8", 0, bytesRead);
       if (start > 0) {
         const firstNewline = text.indexOf("\n");

src/commands/channels/logs.ts

@@ -3,9 +3,10 @@ import fs from "node:fs/promises";
 import { normalizeLowercaseStringOrEmpty } from "@openclaw/normalization-core/string-coerce";
 import { theme } from "../../../packages/terminal-core/src/theme.js";
 import { normalizeChannelId as normalizeBundledChannelId } from "../../channels/registry.js";
+import { readFileWindowFully } from "../../infra/file-read.js";
 import { parseStrictPositiveInteger } from "../../infra/parse-finite-number.js";
 import { getResolvedLoggerSettings } from "../../logging.js";
-import { readLogWindowFully, resolveLogFile } from "../../logging/log-tail.js";
+import { resolveLogFile } from "../../logging/log-tail.js";
 import { parseLogLine } from "../../logging/parse-log-line.js";
 import { listManifestChannelContributionIds } from "../../plugins/manifest-contribution-ids.js";
 import { defaultRuntime, type RuntimeEnv, writeRuntimeJson } from "../../runtime.js";
@@ -87,7 +88,7 @@ async function readTailLines(file: string, limit: number): Promise<string[]> {
       return [];
     }
     const buffer = Buffer.alloc(length);
-    const bytesRead = await readLogWindowFully(handle, buffer, start);
+    const bytesRead = await readFileWindowFully(handle, buffer, start);
     const text = buffer.toString("utf8", 0, bytesRead);
     let lines = text.split("\n");
     if (start > 0 && prefix !== "\n") {

src/infra/file-read.ts

@@ -0,0 +1,23 @@
+import type { FileHandle } from "node:fs/promises";
+
+/** Fills a bounded positional-read buffer unless the file reaches EOF. */
+export async function readFileWindowFully(
+  handle: FileHandle,
+  buffer: Buffer,
+  position: number,
+): Promise<number> {
+  let bytesRead = 0;
+  while (bytesRead < buffer.length) {
+    const result = await handle.read(
+      buffer,
+      bytesRead,
+      buffer.length - bytesRead,
+      position + bytesRead,
+    );
+    if (result.bytesRead === 0) {
+      break;
+    }
+    bytesRead += result.bytesRead;
+  }
+  return bytesRead;
+}

src/logging/log-tail.ts

@@ -1,6 +1,7 @@
 // Log tail helpers read recent log lines with optional parsing and redaction.
-import fs, { type FileHandle } from "node:fs/promises";
+import fs from "node:fs/promises";
 import path from "node:path";
+import { readFileWindowFully } from "../infra/file-read.js";
 import { getResolvedLoggerSettings } from "../logging.js";
 import { clamp } from "../utils.js";
 import { redactSensitiveLines, resolveRedactOptions } from "./redact.js";
@@ -26,28 +27,6 @@ function isRollingLogFile(file: string): boolean {
   return ROLLING_LOG_RE.test(path.basename(file));
 }
 
-/** Fills a bounded positional-read buffer unless the file reaches EOF. */
-export async function readLogWindowFully(
-  handle: FileHandle,
-  buffer: Buffer,
-  position: number,
-): Promise<number> {
-  let bytesRead = 0;
-  while (bytesRead < buffer.length) {
-    const result = await handle.read(
-      buffer,
-      bytesRead,
-      buffer.length - bytesRead,
-      position + bytesRead,
-    );
-    if (result.bytesRead === 0) {
-      break;
-    }
-    bytesRead += result.bytesRead;
-  }
-  return bytesRead;
-}
-
 /** Resolves a rolling daily log path to the newest existing rolling log when needed. */
 export async function resolveLogFile(file: string): Promise<string> {
   const stat = await fs.stat(file).catch(() => null);
@@ -148,7 +127,7 @@ async function readLogSlice(params: {
 
     const length = Math.max(0, size - start);
     const buffer = Buffer.alloc(length);
-    const bytesRead = await readLogWindowFully(handle, buffer, start);
+    const bytesRead = await readFileWindowFully(handle, buffer, start);
     const text = buffer.toString("utf8", 0, bytesRead);
     let lines = text.split("\n");
     if (start > 0 && prefix !== "\n") {