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

With no annotations, the description carries the full burden and does so richly: it discloses that catalog queries need no credentials or payments, that results are point-in-time evidence and not demand/trust/settlement/future-rank proof, that the payment challenge is bound to a specific GET URL rather than mcp://, and that retries must repeat identical authorized arguments and credential. This is exactly the auth, retry, and limitation context an agent needs.

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?

Despite being one dense paragraph, it is front-loaded with the core purpose and every sentence contributes operational information (parameter conditions, auth behavior, result limits). It is appropriately sized for a 9-parameter audit tool, though the lack of sentence-level structure makes it harder to scan.

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 complex 9-parameter tool with no annotations and no output schema, the description covers purpose, parameter conditions, auth/payment behavior, and result limitations thoroughly. The main remaining gap is the shape of the returned evidence, which is not described and there is no output schema to compensate.

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 already 100%, so the baseline is 3, but the description adds real meaning beyond the schema: it states runtimeUrl takes precedence over expectedPriceUsd, that runtimeUrl is GET-only and requires a matching pathname, and that method defaults to GET. That precedence and constraint information is not derivable 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 states a precise verb+resource: it measures one service's brand-blind rank, source-family coverage, canonical-vs-alias identity, duplicates, competitors, and price drift across ten discovery views. It is highly specific about scope, but it never names or differentiates itself from plausible siblings like agent_surface_budget_audit or seller_integrity_audit, so an agent must infer the boundary.

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 gives conditional guidance for internal knobs (set surfaceAudit to check X, materializationAudit to distinguish Y, supply runtimeUrl over expectedPriceUsd since the runtime offer takes precedence). However, it gives no explicit when-to-use-this-tool-vs-alternatives routing among the many sibling audits, leaving the agent to infer the choice.

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