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

Annotations already declare readOnlyHint=true and openWorldHint=true, indicating a safe read operation with potentially broad results. The description adds value by explaining the output structure ('Returns one row per stock with cluster strength') and parameter effects (days_window defaults, supported values). No contradictions are present, and the description supplements the annotations well.

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 extremely concise: one sentence for purpose, one for value proposition, one for return format, and a clean Args list. Every sentence is earned, and the most critical information (what the tool does) is front-loaded. No wasted words.

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?

Despite lacking an output schema, the description explains the return value (one row per stock with cluster strength). It covers purpose, usage value, and all parameters with their semantics. For a tool with three simple optional parameters, this is fully complete and enables correct invocation.

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 description coverage is 0%, but the description fully documents all three parameters: ticker (optional), days_window (default 30, supported 30/60/90), and min_insiders (default 3). It provides meanings, defaults, and usage hints for days_window beyond what the schema (types/defaults) offers. This excellent compensation makes the tool easily invokeable.

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 purpose with a specific verb 'Detect' and resource 'insider buying clusters.' It distinguishes itself from sibling tools like 'regulatory-filings__get_form_4_insider_trades' by focusing on cluster detection rather than raw trades. The value proposition ('smart-money signal hedge funds pay $200+/mo for') further clarifies its unique offering.

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 implies usage for identifying insider buying clusters and provides parameter guidance (defaults, supported values). However, it lacks explicit when-not-to-use scenarios or references to alternative tools. The context of 'smart-money signal' suggests a specific use case, but no explicit exclusions are given.

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