Lookup Item

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

With readOnlyHint annotation already declaring safety, the description adds meaningful behavioral detail: it uses exact name match first, then falls back to wiki opensearch. This goes beyond the annotation and helps predict tool behavior, though it doesn't detail response structure or error cases.

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 only two sentences, with the primary purpose front-loaded and the usage guidance appended efficiently. No wasted words.

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 simple read-only lookup tool with fully documented parameters and no output schema, the description covers the essential aspects: purpose, resolution strategy, and usage context. It is complete enough for an agent to decide and invoke 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?

The input schema provides complete descriptions for both parameters (query and limit) with 100% coverage. The description does not add parameter-specific details, so the baseline score of 3 is appropriate.

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's function: resolving an item name to a Grand Exchange ID and latest price. It distinguishes itself from siblings by explicitly recommending it over get_item_price when only the name is known, which sharpens the purpose.

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?

The description gives explicit usage guidance: 'Prefer this before get_item_price when you only know the name.' This clarifies when to use this tool versus a specific sibling, though it doesn't exhaustively cover when not to use it.

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