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

Annotations already establish this as a safe, read-only, idempotent operation, and the description does not contradict that. The description adds expectation-setting content about what counts as unusual activity and the fields returned, though it doesn't disclose rate limits, pagination behavior, or empty-result handling.

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 compact: one definitional sentence, one positioning sentence, and a call example. The positioning sentence is somewhat promotional but still communicates the feed's distinctiveness; otherwise, there is no filler.

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 read-only symbol-scoped data fetch, the description plus 100% schema coverage covers required and optional inputs. It doesn't describe return formatting or error cases, but there is no output schema to reconcile and annotations cover safety.

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?

All four parameters have full schema descriptions, so the schema carries the burden. The description reinforces symbol, source, and _apiKey through a concrete example, but adds no additional parameter semantics 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 opens with a concrete object ('Unusual options activity for a symbol') and unpacks it with trade characteristics, sentiment, premium, and contract traded. It also positions itself as 'Intrinio's signature feed for options flow,' which separates it from siblings like intrinio_options_chain or intrinio_target_price. It lacks an explicit verb like 'get' or 'list,' but the example invocation makes the action unambiguous.

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 description conveys the use case: retrieving large/block/sweep options trades flagged by Intrinio, so an agent can infer when to call it. However, it never states when not to use it or names alternatives, leaving routing to inference.

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