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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so safety is covered. The description adds genuine context by disclosing the exact per-expiry payload, which matters because there is no output schema; it stops short of stating ordering, behavior when no expiries fall in range, or account scoping.

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?

One front-loaded sentence identifies the resource first, then lists the per-expiry fields. The field enumeration is dense but each item earns its place by substituting for a missing output schema; no filler sentences.

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 carries the return-value burden and does so thoroughly for a read-only, single-parameter tool. Remaining gaps are minor: sort order of the ladder and whether results are per-account or aggregated.

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 coverage is 100% and the single `days` parameter is documented with its default of 45 in the schema. The description's 'falling before it' reinforces the horizon idea but adds no extra syntax or edge-case meaning beyond the schema.

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 the resource precisely ('the user's upcoming expirations') and enumerates what is broken out per expiry (positions, contracts, ITM shorts, short premium, cost to close, long value, underlyings, earnings/ex-div dates). That is enough to tell it apart from my_option_positions or my_option_payoff, though it never explicitly contrasts with those siblings.

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?

Usage is only implied: the tool returns expirations within a horizon, so an agent can infer it is for forward-looking expiration exposure. There is no explicit when-to-use/when-not statement and no pointer to alternatives such as my_option_positions for current holdings.

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