Get Option Chain

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

With readOnlyHint=true annotation already declaring safety, the description adds useful behavioral context: 'Fast — single API call' and clarifies that it returns strikes for both calls and puts. This goes beyond annotations without contradicting them, though it doesn't cover pagination or return format.

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?

Three short sentences, all informative, with key information front-loaded and no wasted words. It earns every sentence.

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 description covers purpose, return content, performance, and an alternative. For a simple 3-parameter tool with no output schema, this is sufficient for an agent to select and invoke correctly, though it could mention output structure slightly more explicitly.

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 100%, with all parameters including default behavior (month omits returns nearest) already documented. The description itself adds no additional parameter-specific semantics, so the baseline of 3 is appropriate.

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 uses a specific verb ('Get') and resource ('available option expirations and strikes'), and explicitly contrasts with get_option_contracts for specific strikes, distinguishing it from a sibling tool. This is a clear, specific purpose statement.

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?

Provides an explicit alternative: 'To get conids for specific strikes, use get_option_contracts.' This tells the agent when to use this tool vs. an alternative, which is exactly what the dimension requires.

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