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

Goes beyond annotations by detailing the one-off invoke behavior, the connect/checkout links for missing credentials/wallet, and the fact that writes require admin. Aligns with readOnlyHint=false and does not contradict destructiveHint=false.

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 one long, dense paragraph that front-loads the main purpose but is hard to scan. It packs valuable information, but a structured format with bullets or sections would significantly improve readability.

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?

The description covers an impressive amount of context: the full action set, credential and payment edge cases, permission requirements, and the prompt library. It provides some return-value hints (e.g., describe's profile, publish_prompt's link), but without an output schema, not all action responses are specified.

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 descriptions, the description explains key parameters like action values, mcp_id, tool_id, arguments, prompt_vars, and prompt_slug through the workflow. However, many optional parameters (limit, query, immediate, tier_slug, conversation, etc.) remain undefined, so it doesn't fully compensate for the schema's silence.

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 opens with 'The official mcp.ai marketplace — the in-platform catalog of every MCP/tool, AND the way to run them,' giving a clear, specific purpose. It further breaks down the core flow (search → describe → invoke) and lists all 14 actions, distinguishing itself from sibling tools like toolkit_info and authenticate.

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?

Explicitly contrasts invoke vs install: 'Use install only to make an MCP PERMANENT ... prefer invoke for a single/occasional use.' It also explains when to use list_tools, subscribe/cancel, report_bug, request_mcp, and the prompt actions, plus notes that write operations require workspace owner/admin.

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