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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, covering the safety profile. The description adds the behavioral constraint that the tool depends on a prior search (the ID must be a search result), which is valuable context beyond the annotations.

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 extremely concise: two sentences that front-load the key constraint ('Citation only after search; never shopping/detail') and state the core action. Every word earns its place, and there is no 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 simple tool with one parameter, an output schema, and comprehensive annotations, the description is nearly complete. It explains purpose, usage constraints, and parameter origin. The term 'citation' is context-dependent but likely clear given sibling tools. A minor gap is that it doesn't describe what the citation represents, but the output schema is expected to fill that.

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 the parameter 'id' is already described as 'Exact listing ID returned by search.' The tool description only reinforces this ('Fetch one exact ID') without adding new semantic details. Baseline 3 is appropriate given the schema already does the heavy lifting.

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 fetches a citation using an exact ID, and explicitly distinguishes it from shopping/detail operations. The verb 'Fetch' combined with 'Citation only after search' provides a specific resource and scope, differentiating it from siblings like search and shop_vehicles.

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 explicitly tells the agent to use this tool only after a search and never for shopping/detail. It implies the ID must come from a search result, giving clear context. However, it does not name alternative tools or provide explicit when-not-to-use scenarios beyond the 'never shopping/detail' statement.

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