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

Beyond annotations (readOnlyHint=false, openWorldHint=true), the description reveals critical behaviors: invoke runs uninstalled MCPs one-off without bloating the tool list, returns connect/checkout links when auth/payment is needed, and writes require workspace owner/admin. It also discloses the distinction between installed_in_toolkit vs installed_in_workspace.

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 every sentence earns its place—no filler. It is structured around the core flow, then the invoke/install distinction, then the prompt library. The use of semicolons and run-on sentences makes it slightly harder to scan, but the density of information is appropriate for such a complex 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 23 optional parameters, a multi-action surface, and no output schema, the description is remarkably complete. It covers core workflows, auth/payment edge cases, permissions, return value patterns (connect link, checkout link, shareable prompt URL), and the separate prompt library feature. Only minor optional details (e.g., error handling) are omitted.

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 does heavy lifting by explaining the roles of action, mcp_id, tool_id, arguments, prompt_vars, and prompt_slug through workflow walkthroughs. However, it does not systematically define every parameter (e.g., limit, immediate, tier_slug, cancel_comment), leaving some parameters to rely on schema defaults alone.

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, combining catalog discovery and execution. It distinguishes itself from siblings (e.g., report_bug, toolkit_info) by explaining its unique core flow: search → describe → invoke, and separately covering the prompt library.

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 usage guidance with alternatives: 'prefer invoke for a single/occasional use' vs 'Use install only to make an MCP PERMANENT', plus when to use list_tools, request_mcp, subscribe/cancel, and report_bug. It also explains the retry flow after auth/payment fallbacks.

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