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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, openWorld). The description adds real context beyond them: it is snapshot-based rather than live, and the trailing "Pro" signals a paid entitlement requirement. Neither points appear in the structured annotations.

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, front-loaded with the resource and scope, with the analytical purpose second. No filler, though the terse "Pro." fragment is a little clipped relative to the rest.

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 and no annotations explaining the entitlement model, the description should be doing more: it leaves the dte and slot parameters unexplained and doesn't describe the snapshot cadence or return shape. It is adequate for a basic read tool but has clear gaps around the two enum parameters.

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 only 33% (just the ticker description). The dte enum (all/lt8/gte8) and slot enum (AM/PM) have no descriptions, and their meanings are far from self-evident; the description says nothing about either. The "calls, puts, total" phrasing describes output dimensions, not any parameter, so it does not compensate.

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?

States a specific verb+resource: open interest and volume history for one ticker, with the broken-out dimensions (calls, puts, total). Clear on its own, but it never differentiates from the sibling oi_movers, which also concerns open interest, so an agent must guess which one fits.

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?

"Use to see whether options positioning is building or unwinding" gives an implied analytical use case, but there is no explicit when-not guidance and no alternative sibling (e.g. oi_movers) named. The agent can infer intent but must decide on its own when this tool is the right one.

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