Session Management

# Middleware
sid = context.session_id or "anonymous"

# Tool
@server.tool()
def session_id() -> dict:
    sid = server._get_session_id_from_request()
    return {"session_id": sid, "short": sid[:8] if sid else None}

class SessionState(Middleware):
    def __init__(self): self.counts = defaultdict(int)
    async def on_request(self, ctx, nxt):
        sid = ctx.session_id or "anonymous"
        self.counts[sid] += 1
        return await nxt(ctx)

class SessionCache(Middleware):
    def __init__(self): self.c = defaultdict(dict)
    async def on_read_resource(self, ctx, nxt):
        sid = ctx.session_id or "anonymous"
        uri = str(ctx.message.uri)
        cache = self.c[sid]
        if uri in cache: return cache[uri]
        res = await nxt(ctx); cache[uri] = res; return res