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

The description discloses key behavioral traits beyond annotations: invoke works without installing, returns a connect link when credentials are needed, and returns a checkout/top-up link for paid MCPs. It also notes that writes require admin/owner and that describe exposes pricing and auth info.

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 long but information-dense, avoiding fluff and with each sentence delivering unique context. It lacks structured formatting (e.g., bullets), but the narrative flow is logical and front-loaded with the core purpose.

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?

For a tool with 14 actions, 23 parameters, and no output schema, the description provides substantial coverage of core flows, side effects, permissions, and the prompt library. However, it omits return-value details for most actions, though they are often inferable from the action semantics.

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 adds meaning for central parameters (action, query, mcp_id, tool_id, arguments, prompt_*) but leaves many others (limit, immediate, tier_slug, cancel_reason, cancel_comment, report_context, request_details) undocumented. It partially compensates for the overall 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 states that marketplace is the official mcp.ai catalog, listing MCPs/tools and running them. It explains the core flow (search → describe → invoke) and distinguishes its capabilities from siblings like toolkit_info and report_bug.

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?

Explicit guidance is provided: search for discovery, describe for full MCP profiles, invoke for one-off runs even when not installed, and install only for permanent additions. It also recommends invoke over install for occasional use and states that writes 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.