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

Beyond the sparse annotations, the description discloses crucial behaviors: invoke runs tools even when not installed, returns connect/checkout links on auth/payment issues, requires workspace owner/admin for writes, and flags installed_in_toolkit vs installed_in_workspace. No contradiction with 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 every sentence earns its place. It flows logically from the core flow (search→describe→invoke) to the key invoke-vs-install distinction, then to billing/auth/owner requirements, and finally to the prompt library. No fluff or repetition.

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 tool's complexity (14 actions, 23 params), the description covers the core flows, edge cases (credentials, payment, permissions), and the prompt library thoroughly. It lacks explicit return formats for some actions (e.g., search results, list_tools), but with no output schema, it still provides enough context 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 meaningfully explains the main parameters through the workflow (action, mcp_id, tool_id, arguments, prompt_slug, etc.). However, it does not explicitly define all 23 params (e.g., conversation, report_context, immediate, tier_slug), though many are inferable from action names.

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 states the tool is 'The official mcp.ai marketplace — the in-platform catalog of every MCP/tool, AND the way to run them.' This gives a specific verb+resource (catalog and run) and clearly distinguishes it from sibling openfinance tools as the central hub for discovering and executing MCPs.

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 explicitly explains when to use invoke vs install ('prefer invoke for a single/occasional use', 'Use install only to make an MCP PERMANENT'), and covers all other actions: list_tools for callable tools, subscribe/cancel for billing, request_mcp for new MCPs, and separate prompt library actions. This is excellent when-to-use guidance.

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