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

With no annotations, the description carries the full behavioral disclosure burden. It explains the data source, the Form-4 code filter, the distinction between observed_at and happened_at, and adds important interpretive caveats about insider sales. It does not mention pagination, rate limits, or authentication, but for a simple read-style data tool the provided context is substantial.

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 and front-loaded with the essential purpose, then adds caveats, field semantics, and a sibling pointer. Every sentence contributes distinct value with no repetition or 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 simple optional-parameter tool with no output schema, the description is mostly complete: it names key returned fields, explains their meaning, notes the data source, and gives an alternative. It does not describe the full output shape or pagination, but the core information an agent needs to select and invoke the tool is present.

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?

The schema already describes since and min_value, but ticker has no description and the tool description does not compensate for that gap. The parameter names are mostly self-explanatory, and the description adds useful context about the data source, but it does not meaningfully enrich the meaning of the input parameters themselves.

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 is specific and actionable: it identifies the tool as SEC Form 4 open-market insider sells, restricts to Form-4 code S, and explicitly contrasts it with insider_buys for acquisitions. This makes the tool's purpose immediately distinguishable from its siblings without needing to inspect schemas.

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 gives clear usage context: it tells the agent to use this for open-market insider sales, warns that sales carry less informational weight than purchases, and explicitly directs acquisition-related searches to insider_buys. This is strong when-to-use guidance with a named alternative.

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