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

With no annotations, the description carries the behavioral disclosure burden. It usefully adds that the lookup uses DDG-rail settlement history plus public signals, returns an explainable score, and costs $0.002. However, it does not state whether the operation is read-only, requires authentication, or has rate/error behavior.

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 a single compact line with no redundant words, and it front-loads the core purpose and key differentiators: reputation source, explainability, and cost. The telegraphic punctuation is slightly awkward but does not harm 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?

The output schema may cover return values, but the description leaves four optional parameters without explaining selection semantics or the meaning of agent_id_hdr. Without annotations or any alternative routing guidance, it is not complete for a tool with four plausible identifier inputs.

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 description coverage is 0%, so the description must compensate for the undocumented parameters. It identifies three lookup keys (agent_id, seller endpoint, payTo) but leaves agent_id_hdr unexplained and does not clarify parameter formats, precedence, or how the 'seller endpoint' maps to the endpoint property.

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 conveys a reputation lookup keyed on agent ID, seller endpoint, or payTo, drawing on DDG-rail settlement history and public signals, and producing an explainable score. It clearly names the resource and output, though it reads as a fragment rather than a verb-led statement and does not explicitly distinguish itself from the sibling ddg_seller_trust_badge.

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 no guidance on when to use this tool versus alternatives such as ddg_seller_trust_badge or ddg_agent_status. It only states what data the lookup aggregates, with no conditions, exclusions, or selection criteria.

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