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

With no annotations, the description carries the full behavioral burden. It discloses the $0.05 cost, the verification of contracts against issuer registries, and the scope of results, which gives the agent a solid understanding of side effects and outputs. However, it does not explicitly state whether the operation is read-only or mention rate limits, though the nature of the tool implies a non-destructive data lookup.

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 dense paragraph listing many return fields, cost, and an HTTP twin. While every sentence adds value, it is not concise; a bulleted list or separation of core purpose from details would improve scanability. It is front-loaded with the use case, but the volume of information makes it less concise than ideal.

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 tool's complexity and lack of an output schema, the description is thorough: it enumerates the specific data points returned (genuine contract, live price, premium/discount, pool depth, volume, spread, impostor tokens) and mentions edge cases (xStocks not on Base). It also provides cost and an HTTP twin. It lacks error-handling details, but for a data lookup tool this is sufficient.

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 schema already describes the ticker parameter and its accepted forms (stock ticker, ST0x symbol, Coinbase symbol). The description adds examples (NVDA, AAPL, TSLA) but does not introduce new meaning beyond the schema. With 100% schema coverage, the baseline of 3 applies.

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 opens with a specific use case ('need the same stock from every issuer on Base in one call') and enumerates the exact data returned, making the tool's purpose unambiguous. It clearly distinguishes itself from any tool that would return a single issuer's stock or a different aggregation.

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 states a clear trigger condition ('Use this when you need the same stock from every issuer on Base') but does not explicitly name alternative tools or state when not to use it. It implies usage for cross-issuer equity queries, but lacks explicit exclusions or comparisons to siblings.

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