Simple Chat

MCP

Full guide for the MCP SimpleChat action.

What this action does

MCP connects SimpleChat to a Model Context Protocol server and exposes selected server tools to agents. Supported transports include streamable HTTP, server-sent events, WebSocket, and stdio. The action can discover tool metadata and call configured tools by name.

Why and when to use it

Use MCP when a provider already exposes an MCP server and agents should use those tools through a standard protocol. Do not use MCP for a single REST API with a stable OpenAPI spec; OpenAPI is simpler. Do not expose every discovered tool by default if the server has broad or sensitive capabilities.

Before you start

  • An MCP server endpoint or stdio command reachable from the SimpleChat environment.
  • Transport choice: Streamable HTTP, Server-Sent Events, WebSocket, or Stdio.
  • Auth details when required: bearer token, API key header, basic auth, reusable identity, or custom headers.
  • Tool exposure policy: load tools, optional prompts, allowed tool names, and large-result handling.
  • Agents/actions enabled with enable_semantic_kernel.

Configure the action

  1. Choose MCP.
  2. Optionally select Preconfigured MCP Server and Server Preset.
  3. Choose Transport and fill Endpoint. For stdio, fill Command, Arguments, and Environment (JSON).
  4. Choose Authentication Method and fill the shown auth fields or Custom Headers (JSON).
  5. Set Load tools, Load prompts, Validate tool arguments, and Large Result Policy.
  6. Fill Allowed Tool Names to expose only approved tools, or leave blank to expose all discovered tools.
  7. Use Discover Tools to populate Discovered Tool Metadata (JSON).
  8. Set Request Timeout, Connect Timeout, SSE Read Timeout, Retry Count, and Retry Backoff, then use Test Connection.

Example prompts

  • “Use the GitHub MCP tool to summarize open issues labeled customer-impact.”
  • “Call the approved search tool from this MCP server and compare the top results.”
  • “List the tools exposed by this MCP action before deciding which one to call.”

Troubleshooting

Symptom Likely cause Fix
Discovery finds too many tools Allowed Tool Names is blank. Add one approved tool name per line.
Tool calls fail on arguments Arguments do not match the discovered schema. Enable Validate tool arguments and rediscover tools.
SSE connections time out Read timeout is too low or a proxy interrupts the stream. Increase SSE Read Timeout and verify the network path.