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

Beyond the annotations, the description discloses key behavioral traits: invoke runs one-off without installing, writes require workspace owner/admin, credential/payment obstacles return actionable links, and search/describe flag installation status. This is rich transparency for a tool with minimal annotations.

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 the tool is complex and every sentence carries meaningful guidance. It is front-loaded with the core purpose and flow, though a structured format (bullets or sections) would improve scannability.

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 hub tool with no output schema, the description covers the core flows, permission requirements, and failure paths comprehensively. It falls slightly short on explaining all action variants (e.g., resume, immediate) and return behavior, but is robust for selection and invocation.

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 coverage, the description compensates by explaining the main action parameter and the roles of mcp_id, tool_id, arguments, and prompt_vars. However, many of the 23 parameters (limit, immediate, tier_slug, cancel_reason, prompt_slug, request_details, etc.) are not explicitly described, leaving gaps.

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's purpose: the official mcp.ai marketplace that catalogs and runs MCPs/tools. It distinguishes itself from sibling tools by detailing its unique capabilities (search, describe, invoke, install, prompt library) and core flow.

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?

It provides explicit guidance on when to use each action: 'prefer invoke for a single/occasional use' vs 'install only to make an MCP PERMANENT', plus instructions for billing, bug reports, and requests. It even handles edge cases like credentials and wallet balance with a retry flow.

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