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

Annotations already declare readOnlyHint, idempotentHint and destructiveHint=false, so the safety profile is covered. The description adds genuinely new behavioral context: the FIFO open-to-close matching rule, the newest-first ordering, and the fact that outcomes include closed, expired and assigned. It does not mention pagination or truncation behavior at the default limit.

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?

A single dense sentence that front-loads the resource and matching rule, then enumerates returned fields. Every clause carries information, though the field enumeration is list-like and slightly heavy for one 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?

With no output schema, the description usefully enumerates the returned fields (contract, side, dates, contracts, amounts, realized P&L, outcome, days held) and the sort order. Combined with annotations covering safety, an agent has enough to call it correctly; only pagination and the undocumented symbol parameter are 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?

Schema description coverage is 75%, with side, limit and months documented in the schema; only symbol lacks a description. The description adds no parameter-level meaning (no mention of side, limit, months or symbol), so the schema carries the load and the baseline of 3 applies.

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 names a specific resource (the user's closed option trades) and a specific matching method (open-to-close, first in first out), which separates it from open-position siblings like my_option_positions. It does not explicitly name a sibling tool to contrast with, so it stops short of a 5.

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 word 'closed' implies the boundary against open-position tools, and 'matched open-to-close' implies only fully round-tripped trades are returned. However, there is no explicit statement of when to use this versus my_option_orders or my_option_positions, so usage is only implied.

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