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

Annotations already declare readOnlyHint and idempotentHint, so the read-only nature is covered. The description adds meaningful behavioral context beyond annotations: what 13D vs 13G means (active vs passive intent), that only the latest filing per issuer/holder is returned, and that superseded history remains in the archive. This enriches the agent's understanding of result semantics.

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?

Two sentences, front-loaded with purpose. The first sentence states the core function; the second adds critical context about the 13D/13G distinction and deduplication. No filler or redundant repetition of schema details.

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 8 parameters and no output schema, the description does not describe return format or pagination behavior. However, it explains the key behavioral semantics (dedup, filing types) that an agent needs to reason about results. The cursor parameter is self-documented in the schema, and the annotations cover safety. Slightly incomplete without output details, but adequate for a read-only search tool.

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?

Input schema covers 100% of parameters with descriptions, so baseline is 3. The description adds value by explaining the real-world meaning of the schedule_type enum values (13D=ACTIVE intent, 13G=passive), which clarifies how 'activist' and 'passive' map to filing types. This goes beyond the schema's enum labels.

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 clearly states the tool's function: searching 5%+ beneficial-ownership stakes from Schedules 13D/13G. It uses a specific verb ('Search') and resource ('ownership stakes'), and distinguishes itself from siblings by focusing on 13D/13G filings. This is a specific and well-scoped purpose.

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 provides valuable context about the 13D/13G distinction and the 'latest filing wins' deduplication rule, implying when this tool is appropriate. However, it does not explicitly compare to alternative tools like get_insider_trades or list_recent_filings, nor state exclusions. The guidance is implied but not explicit.

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