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

Annotations already declare readOnlyHint/idempotentHint/destructiveHint=false, so the bar is lower, yet the description adds real context: contact details are withheld unless include_contact is set, and it enumerates the returned sub-resources. It also discloses the underlying POST /reporting/registrations/{id} read path, though it doesn't explain rate limits or 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?

Two dense sentences with the resource scope front-loaded and no padding; the trailing endpoint path is the only element of marginal value to an agent selecting the tool.

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?

There is no output schema, so the description carries the return-value burden and does so by naming the content groups returned. For a two-parameter read tool with full annotation coverage, nothing critical is missing, though expansion/format details of nested data are unstated.

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 100%, and the include_contact property description already covers the default-off PII gating, so the sentence 'Contact details only with include_contact' largely repeats structured data. With the schema doing the heavy lifting, the 3 baseline applies.

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?

States a specific verb and resource ('One peer-to-peer registration in full') and enumerates the payload's contents (purchase history, team, totals, child registrations). The singular 'One... in full' implicitly separates it from sibling list tools like qgiv_list_registrations_by_date, though no sibling is named explicitly.

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?

Usage is only implied: an agent can infer this fetches a single registration where the list tools return many, but the description never states when to prefer this over qgiv_list_recent_registrations or qgiv_list_registrations_by_date, nor any prerequisites. The include_contact note is a parameter rule, not a usage guideline.

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