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

Annotations already indicate a safe, read-only, idempotent operation. The description adds valuable context about the content (verified sales, confidence tiers, error rates) but does not disclose any behavioral traits beyond what annotations provide. It could mention that no parameters are needed, but that is evident from the schema.

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 two sentences. The first sentence clearly states what it returns, and the second provides usage guidance. No superfluous 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?

Given no parameters and no output schema, the description is complete. It tells the agent exactly what the summary covers and when to use the tool. A simple tool adequately described.

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?

There are zero parameters, so the baseline is 4 per the guidelines. The description does not need to add meaning beyond the input schema since there is nothing to describe. It implicitly communicates that no parameters are required.

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 starts with 'Returns a short summary' which is a specific verb and resource. It clearly states what the tool does: returns Gembook's valuation and trust methodology. The title also reinforces this. It distinguishes from sibling tools like lookup_card_price and lookup_pop_report.

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 states when to call this tool: 'when a user asks how the prices are computed or whether they can be trusted.' This provides clear context and implicitly tells the agent not to use it for specific price lookups, which are handled by sibling tools.

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