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

The description discloses key behaviors beyond annotations: invoke works even without installation, returns connect/checkout links for auth/payment gaps, writes require workspace owner/admin, and search/describe flag installed_in_toolkit vs installed_in_workspace. This adds significant context beyond readOnlyHint/destructiveHint.

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 a dense, single paragraph that is front-loaded with purpose and core flow, and every sentence carries useful information. However, it lacks any formatting (bullets, sections) that would improve scannability, and its length may reduce quick comprehension.

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 the high complexity (23 params, multiple actions, no output schema, no param descriptions), the description is remarkably complete. It covers the main flow, edge cases (auth, payment, admin roles), the prompt library, and the distinction between permanent install and one-off invoke, making it sufficient for an agent to use the tool effectively.

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 coverage, the description compensates by explaining the 'action' enum values in detail (search, describe, install, invoke, etc.) and the meaning of tool_id, mcp_id, and prompt_vars. However, many parameters such as limit, immediate, tier_slug, conversation, and cancel_reason remain undefined, leaving gaps in full parameter understanding.

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 explicitly states the tool is the official mcp.ai marketplace, covering catalog discovery and execution. It outlines a clear core flow (search → describe → invoke) and defines its scope including capability requests and a prompt library, distinguishing it from sibling tools like toolkit_info.

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?

It provides an explicit decision tree: use search for discovery, describe for details, invoke for one-off runs, install only for permanent use, and list_tools for currently callable tools. It also gives clear guidance on when to use invoke vs install and how to handle credentials/payment via returned connect/checkout links.

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