Bug Description

After adding an MCP server, Hermes reports that the server is connected and that MCP tools are available (for example, "grep connected" and "5 MCP tools available"), but the active session does not expose the concrete MCP tool names or argument schemas in a usable way.

In this state, Hermes appears to know that MCP tools exist, but they are not surfaced like built-in Hermes tools. I can see the count, but I cannot clearly inspect or reference the exact MCP tool names / schemas from the active session.

A full Hermes restart fixed the issue. After restarting, the MCP tools became visible and usable as expected.

This makes the initial post-config state confusing, because the system prompt suggests the tool list has been updated, while the current session still behaves as if the MCP tool registry/schema view has not fully refreshed.

Steps to Reproduce

1. Install Hermes with default settings.
2. Add an MCP server to the Hermes config.
3. Start Hermes (or continue using the current session after adding the MCP server).
4. Observe that Hermes reports:
   • the MCP server is connected
   • MCP tools are available
5. Try to inspect or use the MCP tools from the current session.

Expected Behavior

Once Hermes says the MCP server is connected and tools are available, the current session should also expose the actual MCP tool names and argument schemas clearly enough to inspect and call them, or Hermes should explicitly tell the user that a restart/new session is required before MCP tools become available.

Actual Behavior

Hermes reports that the MCP server is connected and that tools are available, but the current session does not clearly expose the concrete MCP tool names / schemas.

Only after a full Hermes restart did the MCP tools become visible/usable as expected.

Affected Component

MCP / Tool Discovery / Session Refresh / CLI tool visibility

Messaging Platform (if gateway-related)

N/A (CLI)

Operating System

macOS Tahoe 26.3.1

Python Version

3.11.15

Hermes Version

Hermes Agent v0.2.0 (2026.3.12)

Additional Context

• This was reproducible immediately after adding the MCP server.
• The specific server I tested was grep.
• Hermes appeared to know the MCP server was connected and reported the tool count, but the active session still did not expose the actual tool details.
• Restarting Hermes resolved the issue.

Why this is confusing

The current behavior makes it look like MCP registration succeeded and the current session has already been updated, when in practice a restart/new session is still required.

If restart is required by design, Hermes should make that explicit right after MCP configuration/discovery so users do not think the tools are broken or partially loaded.

Proposed Fix (optional)

One of the following would help:

1. Force/require a new session after MCP tool registration changes and clearly notify the user.
2. Refresh the active session's tool registry after MCP discovery.
3. Improve CLI visibility so /tools or a similar command clearly shows MCP tool names and schemas.
4. If live refresh is not supported, show a message like:
   "MCP tools were discovered, but you need to restart Hermes / start a new session before they are available."

Are you willing to submit a PR for this?

No