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

The description discloses important behavioral traits beyond annotations: invoke runs tools without installing them, one-off installs behind invoke require owner/admin, credential gaps return connect links, payment gaps return checkout links, and writes require workspace owner/admin. No contradiction with 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 dense but well-organized around the core flow, key invoke behavior, install vs invoke, and secondary functions. It is long, but nearly every sentence adds needed context for a multi-action tool; a few bullet points or short headings 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 tool with 23 parameters, no output schema, and many actions, the description is remarkably complete: it covers discovery, running, installation, auth, billing, feedback, and prompt library actions. It could still better describe return shapes for search and list_tools, but the core behavior is well 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?

Schema coverage is 0% and there are 23 parameters, so the description must carry the burden. It explains the meaning of the action field and several key parameters (tool_id, prompt_vars, prompt_slug), but many parameters like immediate, tier_slug, conversation, cancel_reason, and prompt_targets remain unexplained.

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 catalog and execution layer, with a specific core flow (search → describe → invoke). It distinguishes itself from siblings by covering catalog discovery, one-off invocation, installation, billing, and prompt-library actions in one tool.

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 gives explicit usage guidance: prefer invoke for single/occasional use, use install only for permanent additions, list_tools for what is callable now, report_bug/request_mcp for feedback/new MCPs. It even explains retry behavior when credentials or payment are needed.

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