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

With no annotations, the description must disclose behavioral traits but only states 'get real-time quotes.' It omits key behaviors such as silent omission of unresolvable symbols (though noted in schema) and the requirement for npub. The description adds minimal value beyond the structured fields.

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, clear sentence of 7 words—no wasted text. It could be more informative without becoming verbose, but it achieves conciseness effectively.

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 has 3 parameters, a required npub for billing, and an output schema, the description is too minimal. It does not explain prerequisites, return format, or how it differs from the many sibling tools. The agent lacks sufficient context for correct invocation.

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 67% (npub and symbols described; dpop_token missing). The description itself adds no parameter information, but the schema already explains symbols handling (e.g., case-insensitive, whitespace tolerance, silent omission). Baseline of 3 is appropriate given moderate coverage.

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 clearly states the tool retrieves 'real-time quotes' for 'one or more symbols,' using a specific verb and resource. However, it does not differentiate from similar siblings like schwab_check_price, which may also involve stock data.

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 provides no guidance on when to use this tool versus alternatives, no context about prerequisites (e.g., authentication via npub), and no exclusions. The agent is left to infer proper usage from the schema alone.

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