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

Annotations already declare readOnlyHint, idempotentHint, and non-destructive behavior, so the safety profile is covered. The description adds useful behavioral context by specifying exactly what data is returned (calls, puts, strike prices, bid/ask, volume, open interest, implied volatility, expirations), going beyond what the schema alone provides.

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 efficient: the first sentence states the core function and key outputs, and the second provides concrete trigger examples. Every sentence earns its place with no filler or redundant restatement.

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 read-only tool with fully documented parameters, the description covers the essential return fields and gives practical usage examples. It loses a point because the closing phrase 'or any options trading question' is overly broad given the many options-related sibling tools, which could steer an agent toward this tool in ambiguous cases.

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%, so the input schema fully documents symbol, type, and expiration. The description's examples add natural-language mappings for the parameters, but they do not add meaningful structural or format details beyond the schema, 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 clearly states a specific verb-resource pair ('Get the options chain for a stock') and lists the returned data fields, making the tool's purpose obvious. However, it does not explicitly distinguish this from the sibling options_history_chain or other options-related tools, so it falls just short of full sibling differentiation.

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 'Use this for' section gives concrete example queries such as 'show me AAPL options' and 'what are the puts on Tesla?', providing clear context for when an agent should select this tool. It does not mention when not to use it or name alternatives like options_history_chain, so it lacks explicit exclusions.

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