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

Annotations already declare read-only, non-destructive, closed-world behavior, so the safety profile is covered. The description adds genuinely non-obvious behavioral context: it will never surface owner or agent contact details, which tells the agent what content to expect and what the card deliberately omits.

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, front-loaded with what is rendered, then when to use it, then a constraint. No filler, though the usage sentence is thin relative to the space it occupies.

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 one-parameter render tool with no output schema, the description covers what gets displayed and a key privacy constraint. It lacks only edge-case behavior such as what happens with an invalid or expired listing_id.

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 single listing_id parameter has 0% schema description coverage, but its name and uuid format are largely self-describing. The description adds nothing about the parameter (e.g., where to obtain a valid ID), so it neither compensates nor misleads.

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 concrete verb and resource — renders one Homejourney listing as a visual card with photos, details, and an open button. The 'visual card' framing separates it from the data-oriented sibling get_listing_details, though the description never names that sibling 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?

"Use this when the user wants to look at one listing" gives a usable trigger condition, but with siblings like get_listing_details, render_shortlist, and compare_listings present, it offers no contrast or exclusion to help disambiguate a pure-data fetch from a UI render.

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