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

Beyond annotations, the description discloses key behaviors: 'invoke works even when the MCP is NOT installed', returns a connect link for missing credentials, and a checkout/top-up link for empty wallets. It also states that 'Writes (install/uninstall/subscribe/cancel and the one-off install behind invoke) require workspace owner/admin.' This is rich, actionable context with no contradiction.

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 thorough but long, with multiple paragraphs and many clauses packed into single sentences. It is front-loaded with the core purpose, but the length reduces clarity and could be structured with bullet points or sub-sections to improve scannability.

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 covers the full operational workflow, including auth requirements, one-off vs permanent install, billing/credential handling, and the prompt library. This is exceptionally complete context for an agent to select and invoke this tool correctly.

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 must compensate but does not systematically explain most parameters. It mentions action names and implies tool_id/arguments for invoke, but leaves many parameters (limit, immediate, prompt_body, tier_slug, cancel_reason, etc.) unexplained, giving the agent insufficient per-parameter guidance.

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 the tool's role as 'the official mcp.ai marketplace — the in-platform catalog of every MCP/tool, AND the way to run them.' It uses specific verbs like search, describe, invoke, and install, and explicitly maps the core flow, distinguishing this from sibling tools like authenticate or connect.

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 gives explicit when-to-use guidance: 'Use install only to make an MCP PERMANENT... prefer invoke for a single/occasional use.' It also explains when to call list_tools, subscribe/cancel, report_bug, and request_mcp, and contrasts invoke with install behavior.

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