How do I replace the MCP client logger?

[Banbury]

I am trying to write a console app with VoltAgent. I have changed the agent logger to write only to file. But the MCP client is still logging to the console, which disrupts my UI. How do I configure it to not write to the console or turn it off altogether?

[aniruddhaadak80]

This feels like a configuration gap between the top-level VoltAgent logger and whatever logger the MCP client creates internally. If the MCP client is instantiating its own console transport instead of inheriting the agent logger, users with TUI or console apps will keep hitting this mismatch.nnI would hope for either dependency injection of the MCP logger or a documented way to disable console output at the client layer. Even a temporary env flag would help until the logging surface is unified.

[Banbury]

I have looked through the sources, and the MCP logger seems to be hard-coded and not configurable. The pino logger used in VoltAgent also has no way to configure it globally. All in all the logging could be improved a lot.

[pandego]

I dug through the current source - today there does not seem to be a separate MCP-client logger setting.

What happens right now is:

• MCPClient builds its logger from getGlobalLogger().child({ component: "mcp-client", ... })
• if no global logger is registered yet, getGlobalLogger() creates the default console logger
• MCPClientConfig does not expose a logger override

So if you only changed an agent-specific logger, that would explain the behavior: the MCP client is not using the agent logger, it is using the global logger.

The practical workaround is to register a file-only global logger early, before MCP clients/tool discovery are created. For example:

const logger = createPinoLogger({
  name: "my-app",
  // transports / destination configured for file only
});

new VoltAgent({
  logger,
  agents: { ... },
  server: honoServer(),
});

If your MCP client is being created outside VoltAgent, make sure the global logger is set before that code path runs.

So short version:

• per-MCP logger replacement: I do not think this exists yet
• global logger replacement: yes, and that is the path MCP appears to follow
• if you need zero console output, set a custom global logger rather than only changing the agent logger

If helpful, I can open a small feature request for a logger option on MCPClientConfig or a dedicated MCP logging adapter so this is configurable explicitly.

[Banbury]

@pandego I am not using the VoltAgent class, but run the Agent directly. So I would appreciate it, if MCP loggers could be configured separately or if a global logger configuration existed, that applies to all classes equally.