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

Discloses key behaviors beyond annotations: invoke runs tools even when not installed, does not bloat the tool list, returns connect/checkout links when needed, requires workspace owner/admin for writes, and prompt links open without login. This is far richer than the generic readOnlyHint/openWorldHint flags and adds actionable behavioral context.

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 dense and information-rich, covering the main flow, special invoke behavior, billing, permissions, and the prompt library. Every sentence adds value, but the single-paragraph structure could benefit from bullet points or short sections to improve scannability for such a multi-action tool.

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 (14 actions, 23 params, no output schema), the description is remarkably complete: it explains the core discovery/running cycle, special invoke semantics, install vs invoke, list_tools, billing actions, bug reporting, MCP requests, and the prompt library, including permission and login implications.

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?

The description explains the core parameters through the flow narrative (action, tool_id, mcp_id, prompt_slug/prompt_vars implied) and covers the main action branches. However, with 23 parameters and 0% schema description coverage, it does not individually clarify lesser-used ones like immediate, cancel_comment, request_details, or prompt_targets, leaving some reliance on parameter names.

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 identifies the tool as the official mcp.ai marketplace, a catalog and runtime for MCPs, with a concrete search→describe→invoke flow. It distinguishes itself from sibling tools by positioning itself as the meta-tool that discovers and runs others, not a specific domain action.

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?

Provides explicit decision guidance: 'prefer invoke for a single/occasional use' vs 'Use install only to make an MCP PERMANENT', plus when to use search/describe/list_tools. It also explains when invoke returns connect/checkout links and to retry afterward, and notes owner/admin requirements for writes.

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