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

With no annotations, the description must carry the full behavioral burden. It discloses the cost ($0.02 USDC via x402, Base) and data sources (Tradier, Massive/Polygon, Alpaca), which are important. However, it omits rate limits, authentication details beyond payment, error handling, and whether the operation is read-only (though implied).

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, information-dense sentence with no wasted words. The cost and core functionality are front-loaded, and the parenthetical list is efficient.

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 output schema and no annotations, the description should ideally explain the return structure and more behavioral details. It lists the data points but does not describe the output format or error conditions, leaving gaps for an agent to call it correctly.

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 0% for the single 'symbol' parameter. The description adds that it is 'for a US ticker', clarifying the expected value type, but does not specify format (e.g., 'AAPL' vs 'AAPL.US') or constraints. It partially compensates but leaves ambiguity.

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 resource (US ticker) and enumerates the data returned (live quote, completed-session levels, cross-check), making the tool's function clear. However, it does not explicitly differentiate from sibling tools like analog_scan or mirror_projection, so it falls short of a 5.

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?

No guidance is provided on when to use this tool versus alternatives. It mentions the tool is paid and for US tickers, but does not state when to choose it over siblings or any exclusions.

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