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

Annotations already declare readOnlyHint and idempotentHint, and the description adds significant behavioral context: 'Latest filing per (issuer, holder) wins, so results are current stakes; superseded history stays in the archive.' It also flags 13D as potentially market-moving, which helps interpret results. No contradiction with 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 terse sentences front-load the core purpose and then deliver the two most decision-relevant behavioral facts. Every clause earns its place with no filler or 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?

For a read-only search tool with a fully self-documenting schema and no required parameters, the description covers the domain-specific meaning that structured fields cannot: the 13D vs 13G distinction, the 5% threshold, and latest-filing-wins semantics. It could be slightly richer about output shape or explicit alternatives, but nothing essential for invoking the tool is missing.

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%, so the baseline is 3. The description adds meaning beyond the schema by decoding 13D vs 13G in terms of activist/passive intent and by clarifying that results reflect the latest filing per (issuer, holder). This enriches schedule_type and the overall result interpretation.

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 ('Search'), a concrete resource ('5%+ beneficial-ownership stakes'), and a precise source ('Schedules 13D/13G'). The 13D/13G distinction and latest-filing-wins rule clearly differentiate it from siblings like get_insider_trades and list_recent_filings.

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?

Provides clear context by explaining that 13D represents active/activist intent and 13G represents passive ownership, which directly informs schedule_type usage. It does not explicitly name sibling alternatives or give 'use this instead of X' guidance, so it stops short of full routing support.

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