Expiration Dates

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

Annotations already declare readOnlyHint=true, so the tool is known to be safe. The description adds the behavioral context of returning a list of all available expiration dates and its usefulness for planning trades or term structure, going beyond the annotation.

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 highly concise, with a clear first sentence, bullet-pointed usage examples, and structured Args/Returns sections. Every sentence earns its place without redundancy.

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?

The tool is simple with a single parameter and no output schema. The description adequately explains the return (list of dates) and provides usage context. It doesn't mention edge cases like market exclusivity or ordering, but given the simplicity, these are not critical gaps.

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?

With 0% schema description coverage, the description should fully compensate for the parameter. It only provides 'ticker: Stock symbol', which is minimal and adds little beyond the parameter name itself. There is no additional format, constraints, or examples.

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 gets available expiration dates for a ticker, with a specific verb and resource. It also distinguishes from siblings like get_term_structure by explicitly framing it as 'when the user asks about expiration dates'.

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 says 'Use this tool when the user asks about' and lists specific scenarios (when options expire, available expiration dates, weekly vs monthly). It provides clear context without requiring inference.

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