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

The description goes far beyond annotations by disclosing subtle behaviors: use acquired_disposed_code rather than transaction_code, split_adjusted block semantics, data_quality_flags gating behind include_anomalies, page-scoped anomalies_excluded_on_page, joint filing warnings, plan-window truncation, 403 behavior still being charged, and 30 credits per page. Annotations already mark the tool read-only/idempotent/non-destructive, so the description meaningfully adds behavioral context above that baseline.

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 dense but every sentence carries operational value: output structure, field interpretation, anomaly behavior, warnings, error handling, pricing, and endpoint. It is front-loaded with the core purpose and then layers critical caveats, making the length justified for a 10-parameter financial data tool with many edge cases.

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 tool with no output schemaholpen, the description covers the nested filing->transaction structure, key fields, anomaly suppression, warning semantics, plan limits, error conditions, credit cost, and endpoint. It also contextualizes the page-scoped anomaly count against get_insider_stats. Nothing essential to calling this tool correctly appears 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 extra semantic clarity for several parameters, including how include_anomalies affects row withholding, how transaction_code unknown values are dropped and reported, and how ticker/insider_cik interact with coverage and filtering. It doesn't exhaustively walk every parameter, but it meaningfully supplements 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 specific statement: 'Insider-trade filings and their transactions, nested filing -> transactions,' precisely naming the resource and its structure. It also distinguishes itself from search_insider_trades by noting that unanchored screening belongs there, and the title mirrors the tool's exact scope.

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?

It explicitly states the required anchoring inputs ('Requires ticker and/or insider_cik'), names the alternative for unanchored searches ('for unanchored screening use search_insider_trades'), and gives important usage caveats such as ticker coverage returning 403, insider_cik-only filtering, plan history windows, and credit costs. This is strong when-to-use guidance.

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