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

Beyond annotations, the description discloses key behaviors: invoke runs tools without installing them, writes require workspace owner/admin, auth/payment scenarios produce connect/checkout links, and search/describe flag installation status. This adds significant context about side effects and prerequisites that annotations alone do not provide. No contradiction found.

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?

The description is long but appropriately so for a tool with 23 parameters and 14 actions. It is front-loaded with the core purpose, then organizes the flow with 'Core flow', 'KEY', and clear distinctions. Every sentence adds useful information, and the density is justified by the tool's complexity.

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?

Given the tool's complexity and lack of output schema, the description is remarkably complete. It covers all major functional areas: discovery, execution, installation, billing, feedback, requests, and the prompt library, including authentication and payment behaviors. Minor omissions like resume are negligible given the breadth covered.

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?

With 0% schema description coverage, the description compensates substantially by explaining the meaning of the action enum values (search, describe, invoke, install, subscribe, etc.) and the roles of core parameters like mcp_id, tool_id, and prompt-related fields. It adds meaning beyond the bare input schema even though not every parameter is individually addressed.

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 that this is 'the official mcp.ai marketplace — the in-platform catalog of every MCP/tool, AND the way to run them.' It specifies the resource (MCPs and prompt library) and distinct actions (search, describe, invoke, install), differentiating it from sibling tools by emphasizing it is both catalog and execution engine.

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 provides explicit when-to-use guidance: 'prefer invoke for a single/occasional use' vs 'install only to make an MCP PERMANENT.' It explains the core flow (search → describe → invoke), when to use list_tools, and how to handle authentication and payment via connect/checkout links. This clearly distinguishes between alternatives.

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