Middleware Demo Plugins
Two example plugins demonstrating PluginApi.register_middleware() — the
plugin-based mechanism for injecting AgentScope MiddlewareBase instances
into the agent's reasoning loop.
Included Demos
| Plugin | Hook | Behavior |
|---|---|---|
tracing-middleware |
on_acting |
Logs every tool call (name, duration) to a file. Conditionally activated only when QWENPAW_TRACE env var is set. |
thinking-log-middleware |
on_reasoning |
Prints model reasoning stream events to stdout ([THINKING] for chain-of-thought, [TEXT] for text responses). Always active. |
Installation
These plugins are not auto-loaded. Install them explicitly:
# While QwenPaw is running (hot-load, no restart needed):
qwenpaw plugin install plugins/middleware-demo/tracing-middleware
qwenpaw plugin install plugins/middleware-demo/thinking-log-middleware
# Or when QwenPaw is stopped (loaded on next start):
qwenpaw plugin install plugins/middleware-demo/tracing-middleware
qwenpaw plugin install plugins/middleware-demo/thinking-log-middleware
Uninstall
qwenpaw plugin uninstall middleware-demo-tracing
qwenpaw plugin uninstall middleware-demo-thinking-log
How It Works
Each plugin registers a middleware factory via api.register_middleware(factory, priority=N).
The factory is called once per request during agent assembly:
def my_factory(ctx, agent_config):
# ctx: HookContext (session_id, agent_id, workspace_dir, ...)
# agent_config: AgentProfileConfig
#
# Return a MiddlewareBase instance to activate, or None to skip.
return MyMiddleware()
The returned middleware wraps the agent's inner reasoning loop using the
standard AgentScope 2.0 onion model (on_reply, on_reasoning, on_acting).
Priority
Lower priority values run as the outermost layer (execute first on the way in, last on the way out). The built-in middlewares use implicit ordering; plugin middlewares append after them sorted by priority.