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

Annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=false, so the safety profile is covered structurally. The description adds real context beyond that: results are limited to ACTIVE listings (implying removed/expired ones are excluded), the fields each result carries, and the domain constraint that TraydStar is barter-only with no purchase semantics. It does not mention rate limits or auth requirements, but those are not implied by the annotations either.

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 sentences, front-loaded with the usage trigger, then the search facets and return shape, then a short domain caveat that prevents an agent from treating listings as purchasable. No filler or repetition of the schema.

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 10-parameter, zero-required search tool with an output schema and full annotation coverage, the description covers purpose, trigger, scope (active only), and result contents. The 'TraydStar is barter only' caveat is valuable domain context, though slightly tangential to invocation. Return-value details are largely duplicated from the output schema, so nothing critical is missing.

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 each of the 10 parameters has its own description, so the schema carries the semantic load. The description only loosely gestures at the facets ('by text, category, or type') without adding format, default, or interaction details beyond the schema, so the 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 and resource ('Searches active listings by text, category, or type') and scopes it to active listings, which cleanly separates it from get_listing (single fetch), list_my_listings, and list_saved_listings. The return-field list further pins down what an agent can expect, so the tool is identifiable without opening the 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?

'Use this when the user wants to find goods or services offered for barter' gives a clear triggering condition for a search tool. It does not name the alternative retrieval tools (get_listing, list_my_listings, list_saved_listings) or state when not to use it, so it stops short of full routing guidance.

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