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

The description adds significant context beyond the annotations: invoke runs a tool even if not installed without adding to the toolkit, returns a connect link when credentials are needed, and returns a checkout link if the wallet is empty. It also discloses that install/uninstall/subscribe/cancel and the one-off install behind invoke require owner/admin, and distinguishes permanent vs. temporary execution. This is rich behavioral detail that helps the agent predict side effects.

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 highly information-dense, with no wasted flowery language. It is front-loaded with the core flow and then covers install vs. invoke, permissions, and the prompt library in a structured way. Some sentences are complex and packed with multiple ideas, which slightly hurts skimmability, but overall every sentence earns its place.

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 multi-action tool with 23 parameters and no output schema, the description is remarkably complete: it explains the full workflow, billing/auth-edge cases, permission requirements, the distinction between one-off and permanent installation, and the separate prompt library feature. It does not explicitly describe return formats, but the important decision-driving context is all present.

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 23 parameters and 0% schema description coverage, the description must compensate. It does explain the central `action` enum values and key parameters like mcp_id, tool_id, prompt_slug, prompt_body, and prompt_vars through the narrative flow. However, many parameters such as limit, query, immediate, tier_slug, message, request_name, cancel_comment, report_context, and prompt_targets are not individually described. The description provides high-level semantics but does not fully document each parameter's purpose.

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, the in-platform catalog of every MCP/tool and the way to run them. It goes beyond a simple verb+resource by outlining the core search→describe→invoke flow, though the breadth of actions (install, subscribe, prompt library) makes the ultimate purpose somewhat multiplexed. It is not a tautology and is distinguishable from sibling tools like authenticate or connect, but it does not explicitly name them.

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, actionable guidance: use the core flow search→describe→invoke, prefer invoke for one-off use versus install for permanent toolkit membership, and retry after the user completes a connect/checkout flow. It also states when writes require workspace owner/admin and when to use prompt library actions. This is a model of when-to-use versus alternatives.

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