stock_options_chain

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

Annotations already indicate readOnlyHint=true and destructiveHint=false. The description adds valuable context: error handling for invalid expiry, default return of nearest expiry, and listing of available_expiries. This goes beyond annotations, though rate limits or authentication are not mentioned.

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?

Concise, well-structured description with a brief intro, usage examples, and clear Args/Returns sections. At about 10 lines, every sentence adds value and is front-loaded with purpose and usage.

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?

For a simple 2-parameter tool with no output schema, the description covers purpose, usage, parameters, and return structure (listing fields like underlying_price, call_count, etc.). It does not mention edge cases like empty chains or missing data, but the information provided is sufficient for an AI agent to invoke the tool 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 has 0% description coverage, so the description fully compensates. It explains symbol as a US stock symbol with examples, and expiry as an optional ISO date that must match available_expiries, including the error behavior. The default behavior when omitted is also described.

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 it returns the full options chain for a US stock symbol and one expiry, with specific examples like 'show me AAPL puts expiring next Friday'. It differentiates from siblings such as stock_options_unusual_activity by focusing on the standard chain rather than unusual activity.

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?

Explicit usage examples are given, such as when a user asks for an options chain or wants to inspect bid/ask/IV/volume. The description also explains behavior when no expiry is provided (returns nearest expiry). It does not explicitly mention when not to use or list alternative tools, but the context is clear.

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