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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the description doesn't need to repeat safety. It adds a behavioral guarantee that email/phone are never returned—a privacy-related disclosure. It also mentions the account requirement. This goes beyond annotations. No contradiction.

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 sentence that clearly states the purpose and includes a privacy note. No redundancy or fluff.

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 read-only summary tool, this is adequate: it lists what's included, states what's excluded (contact details), and notes the account requirement. Has good annotations and a well-documented parameter.

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 one optional parameter (weddingId) is fully described in the schema with 100% coverage. The description also explains when it's needed (only when multiple weddings). This is clear and complete.

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 the tool returns a summary of the couple's Wedyesday guest list, enumerating specific data points (headcount, groups, contact details, plus_ones, children). This specific verb+resource+scope distinguishes it from siblings like get_my_wedding_dashboard, which covers a broader overview.

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 mentions the prerequisite of requiring a connected Wedyesday account. However, it doesn't explicitly contrast with alternatives; the sibling list includes get_my_wedding_dashboard which might also show guest info, but the description doesn't point to that. For a read-only summary, it's clear enough when to use.

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