List watches

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

With no annotations, the description carries the behavioral burden. It discloses that the tool returns stored prices from the last refresh rather than live values, which is a meaningful behavioral trait. It does not mention pagination, ordering, or empty-list behavior, but for a simple no-parameter listing tool this is acceptable.

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 a single well-structured sentence that front-loads the action and resource, lists the return fields, and ends with the critical freshness caveat. Every word earns its place.

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 no-parameter list tool with no output schema, the description adequately conveys both the return content and the relevant staleness behavior. An agent knows what to expect and how the data relates to watch_refresh.

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 has zero parameters, so there is nothing for the description to clarify. Baseline 4 applies because parameter semantics are not a concern.

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 uses a specific verb ('Show') with a clear resource ('every tracked item') and enumerates the exact data fields returned. This unambiguously identifies it as the watch-list listing tool and distances it from watch_add/watch_remove or price_history.

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 caveat 'Prices are as of the last watch_refresh, not live' provides clear context that this is a read-only snapshot and implicitly points to watch_refresh for more current data. It does not explicitly name alternatives or exclusion conditions, but the freshness context is enough for an agent to choose correctly.

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