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

The description discloses key behavioral traits not covered by annotations: invoke works even when the MCP is not installed, returns a connect link if credentials are needed, and returns a checkout/top-up link if the wallet is empty (with a retry instruction). It also notes that writes require workspace owner/admin and that search/describe flag installation status. This is rich, valuable context.

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 and every sentence adds value, but it is a long single paragraph without visual structuring (bullets or breaks). It could be more scannable, but given the tool's multi-action complexity, the length is justified and information-dense.

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 the full breadth of this complex tool: the core flow, install vs invoke distinction, permission requirements, prompt library, and handling of credentials/payment. Despite no output schema, it explains what to expect (connect/checkout links, tool profiles). It is remarkably complete for a tool with 14 actions and 23 parameters.

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 description coverage, the description must compensate for 23 parameters. It explains the action enum values and the core search/describe/invoke flow, mentioning tool_id and arguments implicitly, but it leaves many parameters (limit, query, immediate, tier_slug, conversation, prompt_* details) unexplained. It adds significant meaning for the primary actions but does not fully compensate for the coverage gap.

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 — the in-platform catalog of every MCP/tool and the way to run them. It lists specific capability requests it covers and outlines the core flow (search → describe → invoke), making the tool's purpose distinct and unambiguous.

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 provides explicit when-to-use guidance: 'prefer invoke for a single/occasional use' vs 'use install only to make an MCP PERMANENT'. It also explains when to use subscribe/cancel, report_bug, and request_mcp, and differentiates prompt library actions. This goes beyond simple context into actionable decision support.

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