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

Annotations give only readOnlyHint=false/openWorldHint=true, so the description carries the burden and delivers richly: invoke runs tools one-off without installing or bloating the tool list, returns connect links when auth is needed, returns checkout/top-up links when the wallet is empty, and discloses that writes require 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?

Every sentence carries real information and the core flow is front-loaded, but the entire description is one dense unbroken paragraph that mixes discovery, execution, billing, permissions, and prompt-library topics. The length is justified by the tool's scope (14 actions, 23 params), yet structure/sectioning would substantially aid parseability.

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 high complexity, 0% schema coverage, and no output schema, the description covers the core flows, credential/payment handling, and write permissions well. However, gaps remain: the 'resume' action is never mentioned, return values for most actions (beyond connect/checkout links and publish's mcp.ai/p/<slug> link) are unspecified, and several params are undocumented.

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%, so the description must compensate. It explains the core action params (action, tool_id, arguments, mcp_id) and the prompt-library actions' roles, but with 23 parameters unexplained in the schema, many are left to inference: report_context, request_details, prompt_category, prompt_title, tier_slug, immediate, cancel_reason, and cancel_comment are never addressed.

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 defines a specific verb+resource: the mcp.ai marketplace for discovering, describing, installing, and running MCPs and for managing prompt-library content. It clearly distinguishes itself from siblings (authenticate, connect, toolkit_info) by being the catalog/execution hub, and it lays out the search→describe→invoke core flow.

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?

Extensive when-to-use guidance is provided: 'prefer invoke for a single/occasional use' vs 'use install only to make an MCP PERMANENT', list_tools for what is callable now, request_mcp when nothing fits, report_bug for feedback, subscribe/cancel for billing. It also names the actions that are write-ops requiring workspace owner/admin.

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