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

It discloses behavior well beyond annotations: invoke works even when the MCP is not installed, missing credentials return a connect link, empty wallet returns a checkout/top-up link, writes require workspace owner/admin, and prompt links open without login. These are meaningful side-effect and requirement details that annotations do not convey.

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 front-loaded with the core flow and includes only relevant behavioral facts. It could be improved with bullet points or separation of the prompt-library section, but every sentence adds information and supports correct selection/invocation.

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 a complex 14-action tool, 23 parameters, and no output schema, the description covers the main flows, permission requirements, and auth/payment redirects. However, it omits the 'resume' action entirely and does not explain several action-specific parameters, leaving notable gaps for full contextual completeness.

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 adds meaning for the core parameters via the flow (action, mcp_id, tool_id, arguments) and explains prompt-related actions. However, with 23 parameters and 0% schema coverage, many parameters remain unexplained (limit, immediate, tier_slug, cancel_reason, report_context, request_details, conversation, etc.), leaving the agent to infer their meanings.

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 of every MCP/tool and a way to run them, with a concrete core flow (search → describe → invoke). It distinguishes itself from siblings like authenticate, connect, and toolkit_info by also covering the prompt library and installation/billing actions.

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 internal guidance: 'prefer invoke for a single/occasional use', 'Use install only to make an MCP PERMANENT', 'list_tools lists what is callable right now', and 'request_mcp asks us to build a NEW MCP when nothing fits.' It does not explicitly compare against sibling tools, but it does clarify when to use each marketplace action.

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