Plugin platforms (IRC, Teams, Google Chat) currently fail with
`No live adapter for platform '<name>'` when a `deliver=<plugin>` cron
job runs in a separate process from the gateway, even though the
platforms are eligible cron targets via `cron_deliver_env_var` (added
in #21306). Built-in platforms (Telegram, Discord, Slack, etc.) use
direct REST helpers in `tools/send_message_tool.py` so cron can deliver
without holding the gateway in the same process; plugin platforms
historically depended on `_gateway_runner_ref()` which returns `None`
out of process.
This change adds an optional `standalone_sender_fn` field to
`PlatformEntry` so plugins can register an ephemeral send path that
opens its own connection, sends, and closes without needing the live
adapter. The dispatch site in `_send_via_adapter` falls through to the
hook when the gateway runner is unavailable, with a descriptive error
when neither path applies. The hook is optional, so existing plugins
are unaffected.
Reference migrations land in the same change for IRC, Teams, and
Google Chat, exercising the hook across stdlib (asyncio + IRC protocol),
Bot Framework OAuth client_credentials, and Google service-account
flows respectively.
Security hardening on the new code paths:
* IRC: control-character stripping on chat_id and message body to
block CRLF command injection; bounded nick-collision retries; JOIN
before PRIVMSG so channels with the default `+n` mode accept the
delivery.
* Teams: TEAMS_SERVICE_URL validated against an allowlist of known
Bot Framework hosts (`smba.trafficmanager.net`,
`smba.infra.gov.teams.microsoft.us`) to block SSRF; chat_id and
tenant_id constrained to the documented Bot Framework character set;
per-request timeouts so a slow STS endpoint cannot starve the
activity POST.
* Google Chat: chat_id and thread_id validated against strict
resource-name regexes; service-account refresh wrapped in
`asyncio.wait_for` so a hung token endpoint cannot stall the
scheduler.
Test coverage: 20 new tests covering happy path, missing-config errors,
network failure modes, and each defensive validation. Existing tests
unchanged. `bash scripts/run_tests.sh tests/tools/test_send_message_tool.py
tests/gateway/test_irc_adapter.py tests/gateway/test_teams.py
tests/gateway/test_google_chat.py` reports 341 passed, 0 regressions.
Documentation: new "Out-of-process cron delivery" section in
website/docs/developer-guide/adding-platform-adapters.md and an entry
in gateway/platforms/ADDING_A_PLATFORM.md naming the hook.
Following PR #21306 which added the new generic plugin-platform hooks,
update the three platform-authoring docs so plugin authors find them:
- website/docs/developer-guide/adding-platform-adapters.md: expand the
'What the Plugin System Handles Automatically' table with env-only
auto-enable + cron delivery + hermes-config UI entries rows. Add
three new sections — 'Env-Driven Auto-Configuration', 'Cron
Delivery', 'Surfacing Env Vars in hermes config' — covering the
hook signatures, plugin.yaml rich-dict format, and the
home_channel-key special case. Update the main register() example
to pass env_enablement_fn + cron_deliver_env_var inline so readers
see them on their first pass. Upgrade the PLUGIN.yaml snippet to
show bare-string + rich-dict + optional_env.
- website/docs/guides/build-a-hermes-plugin.md: the thin platform
example in the build-a-plugin tour now includes env_enablement_fn
and cron_deliver_env_var, plus an optional_env block in the inline
plugin.yaml. Keeps pointing to the developer-guide page for the
full treatment.
- gateway/platforms/ADDING_A_PLATFORM.md: the in-repo reference
shallow-points at the docsite but now names the three new hooks
explicitly so contributors reading the source tree know what
they're for. Also adds teams + google_chat as reference
implementations alongside irc.
Closes remaining functional gaps and adds documentation.
webhook.py: Cross-platform delivery now checks the plugin registry
for unknown platform names instead of hardcoding 15 names in a tuple.
Plugin platforms can receive webhook-routed deliveries.
prompt_builder: Platform hints (system prompt LLM guidance) now fall
back to the plugin registry's platform_hint field. Plugin platforms
can tell the LLM 'you're on IRC, no markdown.'
PlatformEntry: Added platform_hint field for LLM guidance injection.
IRC adapter: Added acquire_scoped_lock/release_scoped_lock in
connect/disconnect to prevent two profiles from using the same IRC
identity. Added platform_hint for IRC-specific LLM guidance.
Removed dead token-empty-warning extension for plugin platforms
(plugin adapters handle their own env vars via check_fn).
website/docs/developer-guide/adding-platform-adapters.md:
- Added 'Plugin Path (Recommended)' section with full code examples,
PLUGIN.yaml template, config.yaml examples, and a table showing all
18 integration points the plugin system handles automatically
- Renamed built-in checklist to clarify it's for core contributors
gateway/platforms/ADDING_A_PLATFORM.md:
- Added Plugin Path section pointing to the reference implementation
and full docs guide
- Clarified built-in path is for core contributors only
Comprehensive 16-point checklist covering every integration point
needed when adding a new messaging platform to the gateway. Built
from the Signal integration experience where 7 integration points
were initially missed.
Covers: adapter, config enum, factory, auth maps, session source,
prompt hints, toolsets, cron delivery, send_message tool, cronjob
tool schema, channel directory, status display, setup wizard,
redaction, documentation, and tests.
