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

The description gives critical behavioral context beyond the annotations: the tool's open-world nature ("openWorldHint: true") is well-supported by the detailed description of how invoke can run tools without installing them. It explicitly clarifies that "invoke works even when the MCP is NOT installed" and details the auth/payment flows: "invoke returns a connect link; if it is paid and the wallet is empty, invoke returns a checkout/top-up link." It also notes that "Writes require workspace owner/admin," which is a key authentication/authorization detail.

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, with three long paragraphs covering many features and flows. While it is informationally rich, it lacks structure (no bullet points, tables, or clear sections), making it harder for an agent to parse quickly. It contains a lot of imperative guidance but is not organized for rapid consumption. Still, every sentence adds value.

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 is exceptionally complete given the tool's high complexity: it covers the primary use case (searching/using MCPs), the alternative flows (installing vs. invoking), the prompt library feature, user roles/permissions, and handling of edge cases (auth, payments, missing credentials).

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?

The description explains the `action` parameter's workflow thoroughly (search/describe/install differences) and touches on undefined parameters through examples like `tool_id` and `arguments` in the invoke context. However, it does not document any of the 23 schema parameters (0% schema coverage) nor explain fields like `immediate`, `tier_slug`, or `prompt_vars`. Since it never explicitly references parameter names, the agent must infer semantics from the schema alone.

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 this is the "official mcp.ai marketplace" and the "in-platform catalog of every MCP/tool" with an explicit core flow (search → describe → invoke). It provides specific examples of capability requests ("find an MCP that does X", "consulta um CPF") and distinguishes itself from the sibling tools by defining its role as a catalog and executor.

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" versus "Use install only to make an MCP PERMANENT in the active toolkit." It also gives concrete workflow context ("Core flow: action=search discovers MCPs by intent → describe returns one MCP's full profile... → invoke RUNS that tool").

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