`scan_plugin` stored `str(p.relative_to(plugin_dir))`, which is `sub\m.py` on
native Windows and `sub/m.py` elsewhere. The string is what compat notices print,
what `plugins_cmd` renders as `file:line`, and what the tests pin, so the same
plugin produced a different report per OS and
`test_scan_plugin_walks_dir_and_skips_tests` failed on Windows (#112576).
`.as_posix()` makes the recorded path stable and portable; nothing consumes the
native form.
A multiplex gateway runs plugin discovery for every served profile, and each
discovery ran plugin_compat.scan_plugin (an ast.parse + two ast.walk passes per
file) over every external plugin: on an 11-profile host that was ~0.4s per
profile of identical work on the gateway boot path, ahead of adapter connect.
The scan result is now cached process-wide on the plugin dir's (relpath,
mtime_ns, size) signature whenever the loaded manifest is used; a changed file
rescans, a caller-supplied manifest bypasses the cache.
Measured over the 11-profile MCP discovery loop on the reporting host:
3.78s -> 3.01s; per empty profile 0.25-0.30s -> 0.11s.
Each copy re-implemented temp+replace by hand and lacked one or more of
fsync, symlink preservation, atomic_replace's Windows-contention retry and
EXDEV/bind-mount fallback, mode preservation, or interrupt-safe temp
cleanup. Three (gateway/session_persistence, cron/suggestions,
agent/shell_hooks) were verbatim inlines of utils._atomic_write; two
modules defined their own directory-fsync helper, now utils.fsync_directory.
plugins/google_meet/_jsonfile.write_json_atomic is deleted (callers use the
canonical helper directly).
Behavior change: every one of these writers now fsyncs the payload, keeps a
pre-existing target's mode, cleans its temp file on BaseException, and
survives Windows AV/indexer contention and cross-device renames the way
config writes already did. cron/suggestions.json is 0600 from creation
(previously chmod'ed after the replace). Skipped on purpose: cron/jobs.py
two-phase staging, gateway/status._write_json_excl (create-only lock),
kanban_transfer staging (not atomic writers); tools/skill_usage.
_write_suppressed_names lives inside a PLUGIN-COMPAT block.
The compat scanner derived a directory from manifest.path by splitting at the
first ':' and falling back to .parent when the result was not a dir. An
entry-point plugin (`vendor_plugin:register`) and a Windows path
(`C:\Users\...`) both collapsed to '.', so a stray .py in the launch directory
was attributed to the plugin and the installed package was never scanned.
After the removal date that disables the wrong plugin. `_scan_root()` now
takes directory manifests verbatim and resolves entry points via
importlib.util.find_spec to the installed package dir; anything unresolvable
scans nothing.
`plugins.allow_deprecated_imports` used bool(), so the YAML string "false"
opened the post-removal bypass. It now requires the literal boolean True, and
summary_lines() says "force-loaded" instead of "DISABLED" when the override is
what kept the plugins running.
Reported-by: ayushnangia (PR #102117 review)
Live PTY check: the banner block named the plugin correctly but was preceded by one stderr
HermesPluginCompatWarning per moved name, duplicating it without the plugin name. warn_once now also
logs at WARNING (agent.log/gateway.log keep the record); cli.main() appends an ignore filter for the
category before plugin discovery. Appended, not overriding: -W error::...HermesPluginCompatWarning
(tests, plugin authors' CI) still wins, verified with the strict test run.
hermes_cli/plugin_compat.py is now the single source of truth for the compat window:
COMPAT_REMOVAL_DATE = 2026-09-14; scan_plugin() statically finds `from F import n`, `import F` + `F.n`,
alias forms and string targets against compat_manifest.json; compat_report() aggregates over the user's
ENABLED external (non-bundled) plugins; disable_reason() decides the loader's skip.
Surfaces (all read from that one report):
* CLI: yellow block under the banner naming plugins + date + `hermes plugins compat` (red + DISABLED after)
* `hermes plugins compat [--json] [path]`: file:line, old -> new per hit; exit 1 while anything remains;
`path` lets a plugin author scan their own checkout
* `hermes doctor`: "Plugin import paths (removed Sep 14, 2026)" section next to the xAI retirement check
* `hermes update`: post-update notice alongside the FTS/curator notices
* Desktop: compat_report() writes HERMES_HOME/.plugin-compat-report.json (deleted when clean); Electron
shows ONE warning dialog per distinct report after the backend is up and persists the dismissal in
userData/plugin-compat-dismissed.json. A new affected plugin, or the date passing, is a new report.
From the date, PluginManager skips a hitting external plugin before importing it, with the reason in
LoadedPlugin.error ("uses N import path(s) removed on 2026-09-14; run `hermes plugins compat` ...") — the
same path a plugin with a broken register() takes, so nothing else is affected. Escape hatch:
plugins.allow_deprecated_imports: true (config_defaults), which only helps until the compat commit is
actually reverted.
Docs: COMPAT_MANIFEST.md (removal date, what-happens table, author instructions), plugin dev guide section.
Tests: tests/test_plugin_compat_notice.py (scanner forms, report scope, date gate + escape hatch, summary
text, report file lifecycle, loader skip via a real PluginManager), electron/plugin-compat-notice.test.ts
(show once, re-show on a different set or on the date passing, malformed file ignored).
Live A/B on this box with a demo plugin on old paths: before the date it loads and the banner/doctor/report
name it; with today=2026-09-14 it is skipped with the reason and the banner turns red; with the escape
hatch it loads again.
Every PLUGIN-COMPAT __getattr__ now calls hermes_cli.plugin_compat.warn_once(facade, name, target) before
resolving, emitting a HermesPluginCompatWarning (FutureWarning) once per process per name: old path, new
path, removal target. Importing a facade for its live API stays silent; only resolving a moved name warns.
COMPAT_MANIFEST.md documents the warning and how to silence it during migration.
Verified the runtime never routes through a pointer: every entry point (run_agent, cli, hermes_cli.main,
gateway.run, tui_gateway.server, web_server, model_tools + tool discovery, hermes_state, cron.scheduler,
browser_tool, mcp_tool, kanban, auth) imports clean and `hermes doctor` runs end to end with the warning
promoted to an error.
Also restores the check_compat_pointers CI step to .github/workflows/lint.yml, which a0be177aac dropped
when the compat layer was regenerated (the lint script itself was present; the workflow step was not).
hermes_cli/plugin_compat.py, tests/test_plugin_compat_warning.py and the two-line insert per facade are
part of the compat layer and go away with it.
