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

Annotations are minimal (readOnlyHint: false, destructiveHint: false) and don't fully characterize the complex behavior. The description adds valuable transparency: invoke works even if MCPs are not installed, requires credentials/connect links, and may return checkout links for empty wallets. It also discloses that install has side effects (makes permanent) and writes need workspace owner/admin. However, it doesn't cover all edge cases like what happens on idempotent re-install or detailed error handling, but contextually rich.

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 dense with purpose-built information for an agent. It front-loads the core flow and uses clear signposts ('Core flow:', 'KEY:', 'Search/describe flag...'). Every sentence carries actionable detail (e.g., conditions for checkout links, permission requirements). It could be seen as slightly long, but it avoids fluff and structures the multiple concerns (catalog, execution, prompts) distinctly.

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 complexity (23 parameters, 16 action values, two major subsystems), the description covers the main behavioral contracts: how invoke handles non-installed MCPs, auth flow via connect link, billing via checkout link, permission requirements for writes, and the prompt library lifecycle. While not exhaustive (no error codes, pagination details), it covers the most critical decision points an agent would need to choose the right action and anticipate outcomes, and it complements the lack of output schema.

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?

Schema coverage is 0% and there are 23 parameters, all with generic names (message, query, arguments). The description does a good job explaining the semantics of the core `action` values and the role of mcp_id/tool_id in the flow, plus the prompt library parameters. Yet, many parameters remain under-specified (e.g., `limit`, `conversation`, `prompt_vars`), but for the primary use cases the description clarifies enough that the agent can infer parameter usage.

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 marketplace catalog and execution engine, with a detailed core flow (search→describe→invoke). It distinguishes itself from siblings by covering both catalog and execution ('in-platform catalog... AND the way to run them'). However, it doesn't explicitly name sibling tools as alternatives, and the scope is broad enough that some may confuse it with the connected MCP tools, but the purpose is clearly articulated.

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?

Explicitly gives when-to-use guidance: 'prefer invoke for a single/occasional use,' 'Use install only to make an MCP PERMANENT in the active toolkit,' and contrasts with list_tools: 'lists what is callable right now.' It also differentiates from the prompt library: 'rather than MCPs'. Alternatives are named and excluded, providing clear decision criteria for the agent.

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