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

Annotations already declare readOnlyHint=true and openWorldHint=true, so safety and external-fetch behavior are covered. The description adds that the data is 'public' and enumerates the returned fields, but says nothing about rate limits, auth, or failure modes; with an output schema also present, this is adequate but not rich.

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 tight sentences with the core purpose front-loaded and the routing hint second. No filler or redundancy.

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-URL detail tool with an output schema and read-only annotations, the description covers purpose, returned content, and discovery routing. Minor gaps (no mention of non-canonical/invalid URL behavior) keep it from a 5.

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?

Only one parameter with 100% schema description coverage, so the schema already documents it. The description adds marginal value by calling the URL 'canonical product url', hinting it must be a product page rather than an arbitrary link, but provides no format example beyond that.

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 (Fetch) and resource (public 1stDibs product details) plus the exact fields returned (pricing, availability, brand, category, description, images). It also names firstdibs_search as the discovery sibling, letting an agent separate this detail-fetch from search without opening either schema.

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?

Explicitly routes the agent: 'Use firstdibs_search to discover listing URLs,' making the search-then-fetch workflow clear. It lacks any when-not guidance (e.g., non-product or non-canonical URLs), so it stops just short of a full when/when-not statement.

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