Files
hermes-agent/hermes_cli/plugins_activation.py
Siddharth Balyan 9039b690fc feat: installed plugins' MCP tools and skills are live in every open chat, no Connect-now (#119644)
Installing a plugin from any surface now makes its MCP servers and skills
usable in every open chat of that profile on the chat's next turn. There is
no Connect-now button, no /reload-mcp, no relaunch.

- hermes_cli/plugins_activation.py::load_and_go_live: after the forced plugin
  rescan, connect the plugin's portable MCP servers one by one
  (register_mcp_servers, the connector flow's call), then refresh that
  profile's open chats and queue a turn note listing the servers, their
  tools and the plugin's skills. activation gains live_now; deferred keeps
  only Python tools and prompt sections.
- MCP tools are deferred behind tool_search / tool_call, so appending them
  (preserve_prefix) leaves the model-facing tool array and the cached prompt
  prefix unchanged; the note rides the existing one-shot turn-note channel,
  so the system prompt stays byte-stable. /reload-mcp keeps its consent gate:
  it is a full rebuild.
- tui_gateway/methods_tools.py: one session walk (_refresh_live_sessions)
  shared by reload.mcp and plugin activation, filtered to the plugin's
  profile home.
- hermes plugins install/enable (another process) asks the running Desktop /
  dashboard backend to do the in-process half through the new
  POST /api/dashboard/agent-plugins/activate, found via the host rendezvous
  record and its session token.
- Desktop: the Connect-now toast and its strings are removed in all six
  locales; the install toast says what went live ("3 tools connected ·
  skill X ready") and warns per server that did not connect.
- Contract: PluginActivation.live_now; regenerated TS/OpenRPC.
- register_skill docstring: plugin skills are listed by skills_list.
2026-09-23 05:11:44 +05:30

202 lines
11 KiB
Python

"""Mid-run plugin activation: what a just-loaded plugin does NOW vs next session (#87770).
One seam for every surface: ``PluginManager.on_plugin_loaded`` fires with one
:func:`plugin_activation_summary` per loaded plugin. Gateway handlers (slash commands, transform hooks,
platform callbacks) are live as soon as the plugin loads; portable MCP servers and skills go live in
the open chats of the plugin's profile (:func:`load_and_go_live`; MCP tools are deferred behind
tool_search, so the cached prompt prefix is unchanged); Python tools and system-prompt sections stay
deferred to the next session (prompt-cache invariant, same as ``/skills install``).
:func:`activate_plugin_now` is what the install / enable / update surfaces call after a successful
config or tree change.
"""
from __future__ import annotations
import logging
from pathlib import Path
from typing import Any, Dict, List, Optional
logger = logging.getLogger(__name__)
# Hooks the gateway consults per inbound/outbound message: live as soon as the registry holds them.
_GATEWAY_TRANSFORM_HOOKS = frozenset({
"transform_llm_output", "transform_tool_result", "transform_terminal_output", "pre_gateway_dispatch",
"gateway_platform_event", "pre_command",
})
def plugin_activation_summary(manager: Any, plugin_key: str) -> Dict[str, Any]:
"""``{name, key, activated_now: {kind: [names]}, deferred: {kind: [names]}}`` for one loaded plugin,
read from what it actually registered (ownership ledger + handler registries), not from what its
manifest promises. Keys appear only when non-empty.
``activated_now``: ``gateway_commands`` (slash names), ``gateway_transforms`` / ``hooks`` (hook names),
``callbacks`` (platforms with a ``register_platform_handler`` factory / Slack action ids).
``deferred``: ``tools`` (tool names; next session), ``prompt`` (section ids; next session),
``mcp_servers`` (the plugin's mcp.json server names exactly as registered; until ``mcp.reload``)."""
loaded = manager._plugins.get(plugin_key)
manifest = getattr(loaded, "manifest", None)
name = getattr(manifest, "name", None) or plugin_key
regs = [r for r in manager._ownership_ledger.get(plugin_key, []) if getattr(r, "active", True)]
kinds: Dict[str, List[str]] = {}
for reg in regs:
kinds.setdefault(reg.kind, []).append(str(reg.key))
now: Dict[str, List[str]] = {}
if kinds.get("command"):
now["gateway_commands"] = sorted(kinds["command"])
hooks = set(kinds.get("hook", ()))
if hooks & _GATEWAY_TRANSFORM_HOOKS:
now["gateway_transforms"] = sorted(hooks & _GATEWAY_TRANSFORM_HOOKS)
if hooks - _GATEWAY_TRANSFORM_HOOKS:
now["hooks"] = sorted(hooks - _GATEWAY_TRANSFORM_HOOKS)
callbacks = sorted(platform for platform, factories in manager._platform_handler_factories.items()
if any(plugin == name for _f, plugin in factories))
callbacks += [f"slack:{a}" for a in kinds.get("slack_action_handler", ())]
if callbacks:
now["callbacks"] = callbacks
deferred: Dict[str, List[str]] = {}
tools = sorted(set(kinds.get("tool", ())) | set(getattr(loaded, "tools_registered", None) or ())
| set(getattr(manifest, "provides_tools", None) or ()))
if tools:
deferred["tools"] = tools
if kinds.get("system_prompt_section"):
deferred["prompt"] = sorted(kinds["system_prompt_section"])
servers = sorted(set(kinds.get("portable_mcp", ())) | {
s for s, owner in manager._portable_mcp_server_plugins.items() if owner == plugin_key})
if servers:
deferred["mcp_servers"] = servers
return {"name": name, "key": plugin_key, "activated_now": now, "deferred": deferred}
def activation_summaries(manager: Any) -> List[Dict[str, Any]]:
"""One summary per loaded (non-deferred-platform, non-errored) plugin — the ``on_plugin_loaded`` payload."""
out = []
for key, loaded in list(manager._plugins.items()):
if getattr(loaded, "deferred", False) or getattr(loaded, "error", None):
continue
out.append(plugin_activation_summary(manager, key))
return out
def find_activation(summaries: Optional[List[Dict[str, Any]]], name: str) -> Optional[Dict[str, Any]]:
"""The summary for ``name`` (manifest name, canonical key, or bare leaf of the key)."""
for entry in summaries or ():
key = str(entry.get("key") or "")
if name in (entry.get("name"), key, key.rsplit("/", 1)[-1]):
return entry
return None
def activate_plugin_now(name: str, *, in_process: bool = True) -> Dict[str, Any]:
"""After an install/enable/update: load the plugin in THIS process (so ``on_plugin_loaded``
subscribers here — the TUI/Desktop server — see it), connect its MCP servers and hand them plus
its skills to the open chats of this profile (:func:`load_and_go_live`), and nudge the running
gateway to load it too over its control socket so live adapters re-wire their handlers. A caller
in another process (``hermes plugins install``) passes ``in_process=False``; the running Desktop /
dashboard backend is then asked to do the in-process half (:func:`notify_serve_backend`). Never raises.
Returns ``{"gateway_reloaded": bool, "activation": summary | None, "restart_required": bool}``.
``activation.live_now`` lists what is usable in open chats now; ``activation.deferred`` what waits
for the next session. ``restart_required`` is True only when no gateway answered (old gateway, not
running)."""
from hermes_constants import get_hermes_home
activation: Optional[Dict[str, Any]] = load_and_go_live(name) if in_process else None
if not in_process:
activation = (notify_serve_backend(name, Path(get_hermes_home())) or {}).get("activation")
answer = None
try:
from gateway.control_socket import reload_gateway_plugins
from hermes_constants import get_default_hermes_root
home = Path(get_hermes_home())
answer = reload_gateway_plugins(home)
if answer is None:
root = Path(get_default_hermes_root())
if root.resolve() != home.resolve(): # a served secondary: the multiplexer's socket
answer = reload_gateway_plugins(root, profile_home=home)
except Exception:
logger.debug("gateway reload-plugins nudge for %r failed", name, exc_info=True)
reloaded = bool(answer and answer.get("reloaded"))
if reloaded and activation is None:
activation = find_activation((answer or {}).get("activations"), name)
return {"gateway_reloaded": reloaded, "activation": activation, "restart_required": not reloaded}
def load_and_go_live(name: str) -> Optional[Dict[str, Any]]:
"""Force-rediscover plugins in THIS process under the caller's profile scope, connect ``name``'s
MCP servers and hand them (and its skills) to this profile's open chats with a turn note. Returns
the activation summary with ``live_now: {mcp_servers, skills}``; ``deferred`` then keeps only what
waits for the next session (Python ``tools``, ``prompt``). None when the plugin did not load."""
try:
from hermes_cli.plugins import discover_plugins, get_plugin_manager
discover_plugins(force=True)
activation = find_activation(activation_summaries(get_plugin_manager()), name)
except Exception:
logger.debug("in-process plugin reload after change to %r failed", name, exc_info=True)
return None
if activation is None:
return None
from hermes_cli.plugins_activation_live import connect_plugin_mcp, live_notice, plugin_skills
servers = connect_plugin_mcp(activation)
activation["live_now"] = {"mcp_servers": servers, "skills": plugin_skills(activation["key"])}
activation["deferred"] = {k: v for k, v in (activation.get("deferred") or {}).items() if k != "mcp_servers"}
import sys
server = sys.modules.get("tui_gateway.server") # loaded == this process hosts chats
note = live_notice(activation)
if server is not None and (servers or note):
from hermes_constants import get_hermes_home
try:
server.refresh_plugin_sessions(Path(get_hermes_home()), note)
except Exception:
logger.warning("open chats were not refreshed after activating %r", name, exc_info=True)
return activation
def notify_serve_backend(name: str, home: Path) -> Optional[Dict[str, Any]]:
"""Ask the running Desktop / dashboard backend (``hermes serve``, found through its host record) to
run :func:`load_and_go_live` for ``name`` in ``home``. None when no backend answers. Never raises."""
try:
import json
import urllib.request
from gateway import host_rendezvous as hr
record = hr.read_record(hr.ROLE_SERVE)
if record is None or not record.port or not hr.record_token_is_consistent(record):
return None
token = hr.read_token(hr.ROLE_SERVE)
request = urllib.request.Request(
f"http://{hr.dial_host(record)}:{record.port}/api/dashboard/agent-plugins/activate",
data=json.dumps({"name": name, "home": str(home)}).encode("utf-8"), method="POST",
headers={"Content-Type": "application/json", "X-Hermes-Session-Token": token})
with urllib.request.urlopen(request, timeout=60) as response: # noqa: S310 — loopback http
return json.loads(response.read().decode("utf-8"))
except Exception:
logger.debug("serve backend activation for %r failed", name, exc_info=True)
return None
def activation_hint(result: Dict[str, Any]) -> str:
"""One honest sentence for CLI surfaces from an :func:`activate_plugin_now` result."""
act = result.get("activation") or {}
live = act.get("live_now") or {}
connected = [s for s in live.get("mcp_servers") or () if s.get("connected")]
lines = []
if connected or live.get("skills"):
tools = sum(len(s.get("tools") or ()) for s in connected)
lines.append(f"Live in open chats now: {tools} MCP tools, {len(live.get('skills') or ())} skills.")
lines.extend(f"MCP server {s['name']} not connected: {s.get('error') or 'unknown error'}"
for s in live.get("mcp_servers") or () if not s.get("connected"))
if not result.get("gateway_reloaded"):
if lines: # live in open chats; a messaging gateway that starts later loads it at boot
return "\n".join(lines)
return "\n".join([*lines, "Restart the gateway for the plugin to take effect:\n hermes gateway restart"])
now, deferred = act.get("activated_now") or {}, act.get("deferred") or {}
parts = []
if now:
parts.append("active in the running gateway now: " + ", ".join(sorted(now)))
if deferred:
labels: Dict[str, str] = {"tools": "tools (next session)", "prompt": "system prompt (next session)",
"mcp_servers": "MCP servers (next session)"}
parts.append("deferred: " + ", ".join(labels.get(k, k) for k in sorted(deferred)))
if not parts:
return "\n".join([*lines, "Gateway reloaded plugins; nothing of this plugin needs a session or restart."])
return "\n".join([*lines, "Gateway reloaded plugins — " + "; ".join(parts) + "."])