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

Beyond annotations (readOnlyHint=false, openWorldHint=true), the description discloses key behaviors: invoke runs even without installation, returns connect/checkout links for auth/payment, and lists that writes require workspace owner/admin. This adds significant contextual value beyond the minimal 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?

The description is long but information-dense, with each sentence covering a distinct aspect. It front-loads the core flow and then expands into behaviors and prompt library. Minor redundancy could be trimmed, but structure is acceptable for the breadth of functionality.

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 primary workflows and caveats (auth, payment, permissions, one-off vs permanent). However, some actions like resume, report_bug details, and prompt publishing specifics are only mentioned by name without usage context. Given the extensive scope, it's reasonably complete but not exhaustive.

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 23 parameters and 0% schema description coverage, the description bears a heavy burden. While it explains the action flow conceptually (e.g., 'describe returns a profile', 'invoke RUNS that tool'), it never explicitly names parameters like mcp_id, tool_id, arguments, or prompt_slug. Agents must infer which schema fields correspond to each action, creating ambiguity for a tool this complex.

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, explicitly listing its core actions (search, describe, invoke, install) and distinguishing it from sibling tools focused on specific integrations. The verb+resource structure is specific 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 guidance on when to use each action: prefer invoke for one-off use, install for permanent toolkit addition, list_tools for current callable tools, request_mcp for new builds, and distinguishes the prompt library separate from MCPs. It also notes permission requirements for writes.

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