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

Annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=false. The description adds useful operational context that the tool needs no docking and returns timestamps plus a trend percentage, though it repeats that it is read-only.

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 front-loaded with the core purpose and scope, then usage context, then operational caveat. Every sentence contributes useful selection or invocation information without unnecessary repetition.

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?

Given the read-only annotations, full schema coverage, and no output schema, the description is complete enough to call correctly. It also summarizes the returned data as historical snapshots with timestamps and a trend percentage, which compensates for the missing output schema.

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 coverage is 100%, so the schema already documents limit, bearer, and item_code. The description still adds value by specifying that item_code comes from get_market and that the history is for exactly one item, while reinforcing the limit range and default.

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 states a specific verb and resource: historical price snapshots for ONE item. It distinguishes itself from get_market by emphasizing history, timestamps, and trend percentage, so an agent can tell what it does 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?

It gives clear usage context: judge whether the current station price from get_market is high or low before buy/sell or place_orders. It also says the tool needs no docking. It stops short of explicit when-not guidance, but the intended use is easy to infer.

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