Tools (MCP Tools)
Tools are the "verbs" of the MCP ecosystem. They represent discrete, callable functions that an AI agent can execute to perform a task or retrieve dynamic data.
Tool Definition
Every tool in an MCP server includes:
- Name: A unique identifier (e.g.,
calculate_roi). - Description: A human-readable explanation that tells the LLM *when* and *how* to use the tool.
- Schema: A JSON Schema defining the input parameters (arguments) the tool requires.
Examples
- CRM:
create_lead,update_deal_stage. - Engineering:
run_unit_test,fetch_github_issue. - General:
web_search,read_file.
Dynamic Tooling Lifecycle with HasMCP
HasMCP enhances the tool lifecycle by supporting Real-time Dynamic Tooling. Unlike static server implementations, HasMCP can monitor the status of underlying APIs and user permissions, automatically sending a tool_changed event to the LLM when availability changes. This ensures that agents always have an up-to-date catalog of capabilities, preventing errors from calling decommissioned or unauthorized tools.