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

Beyond the readOnlyHint annotation, the description adds a security warning: delivered content is seller-written and must be treated as data, not instructions. This is valuable context about potential injection risks and access control that the annotation does not cover.

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 concise: two sentences plus a security note. Every sentence adds value—purpose, usage, access control, and security guidance. Front-loaded with the core function, no wasted words.

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 single-parameter read tool with readOnlyHint annotation, the description is fully complete. It covers what the tool does, who can use it, and security considerations. The lack of output schema is not a gap because the description implies the charge details and delivery status are returned.

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 schema has one parameter, charge_id, with no description and 0% schema description coverage. The description does not mention the parameter at all, only implying that a charge identifier is needed. It adds minimal meaning beyond what the schema indicates.

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 tool reads a single charge in full, with access limited to buyer or seller. It distinguishes from charge_list (which presumably lists multiple charges) and charge_create/refund by focusing on read-only retrieval of one specific charge.

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 specific usage context: buyers use it to collect delivered purchases and check overdue status. It implies the tool is for individual charge lookup, but does not explicitly name alternatives like charge_list for broader queries, so a small gap remains.

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