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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so the safety profile is covered. The description adds real behavioral context beyond that: donor identities are suppressed (privacy), no payment/contribution side effects, and an auth requirement.

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?

Three short sentences with zero filler, front-loaded on what is returned followed by exclusions and prerequisites. Every sentence earns its place.

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?

With no output schema, the description usefully enumerates what the list contains and what is deliberately omitted, and annotations carry the safety profile. An agent has everything needed to decide and call 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?

There is a single parameter with 100% schema description coverage, and the schema already explains that wedding_id is required only when the account manages multiple weddings. The description references 'the selected wedding' but adds no format or selection guidance beyond the schema, so baseline 3 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 ('Lists') and resource ('the selected wedding's registry and honeymoon fund items') and even enumerates the returned fields (descriptions, goal amounts, received totals). It is clearly distinct from the add_/remove_/update_/get_ siblings. It stops short of explicitly naming a sibling to contrast against, which keeps it just below 5.

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?

Gives a clear negative boundary ('does not collect contributions or initiate payments') and a prerequisite ('Requires sign-in'), which helps an agent avoid routing payment flows here. No alternative tool is named for the excluded cases, so it does not reach the explicit when/when-not/alternatives level.

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