mcp_invoke

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations are provided, so the description must cover behavioral traits. It only states 'invoke' without mentioning side effects, return values, error handling, or whether execution is synchronous. The timeout parameter hints at timing, but no explicit disclosure.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Two sentences, front-loaded with the core action ('Invoke any tool'), followed by a prerequisite. No unnecessary words, efficiently structured.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a generic invoke tool without output schema, the description with schema coverage provides enough context to use it correctly. It omits behavioral details like error handling, but given the tool's nature, it is fairly complete.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100%, with each parameter described. The description adds workflow context ('first use mcp_list_servers') but does not add meaning beyond the schema's parameter descriptions, so it meets the baseline of 3.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the tool invokes any tool from any registered MCP server, with a specific verb ('invoke') and resource ('any tool from any registered MCP server'). It distinguishes from sibling tools which focus on server management and listing.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description explicitly advises using mcp_list_servers and mcp_list_tools first, providing clear workflow context. It doesn't state when not to use, but for a generic invocation tool, this is sufficient.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.