Problem

Users running Hermes in a Telegram group with forum topics want different agent profiles (personality, model, system prompt, toolsets) per topic — without creating a separate bot for each profile.

Example: a team group where Topic A is handled by a coding assistant profile and Topic B by a research assistant profile, both using the same bot token.

Current behavior

The Telegram adapter handles forum topics (telegram.py:2088-2090 discovers topic creation), and sessions are already scoped per-chat. But there is no mechanism to map a message_thread_id (topic ID) to a specific agent profile. All topics use the same agent configuration.

Suggested design

Add a topic_profiles mapping in the Telegram platform config:

platforms:
  telegram:
    token: "BOT_TOKEN"
    topic_profiles:
      "12345":          # message_thread_id for Topic A
        personality: "coding-assistant"
        model: "anthropic/claude-sonnet-4"
        toolsets: ["terminal", "file", "web"]
      "67890":          # message_thread_id for Topic B
        personality: "research-analyst"
        model: "openrouter/google/gemini-3-flash"
        toolsets: ["web"]
    # Default profile for topics not in the map
    personality: "general"

The gateway would resolve the profile at message intake time (_build_message_event or handle_message) and pass it through to the agent session.

Complexity

Medium. The gateway already has per-session agent caching (_agent_cache). The change is:

1. Extract message_thread_id from the Telegram update (already available)
2. Look up the topic profile in config
3. Pass profile overrides (model, personality, toolsets) to the agent constructor

Related

• A2A follow-up: adopt named-instance runtime for inter-agent sessions and per-instance identity #2883 — named-instance runtime for inter-agent sessions (architectural foundation)
• feat: per-thread /model, fallback notifications, subagent model in progress #3984 — per-thread /model (overlapping but that's about runtime switching, this is about config-driven routing)