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

With no annotations, the description carries the behavioral burden and does disclose key operational traits: a $0.005 USDC per-call price paid via x402 on Base, and a 25-filing parse cap. It does not cover error behavior, response ordering, or authentication beyond payment, but the critical cost and limit constraints are present.

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 the data scope and field list, followed by the payment requirement. It is dense but every clause earns its place by specifying the returned fields, transaction-code meanings, filing cap, and price.

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?

There is no output schema, so the description must define the return shape; it does so thoroughly by listing owner, role, date, transaction codes, shares, price, shares owned after, and net open-market buys/sells in shares and USD. Combined with the cap and payment details, it is complete enough for an agent to call the tool correctly.

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 100%, so the baseline is 3. The description maps 'last N days' to the days parameter and explains transaction codes, but adds no syntax or edge-case guidance for cik, ticker, or days beyond what the schema already provides.

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 and resource: insider transactions from Form 4 filings. It scopes the data to the last N days and up to 25 parsed filings, and lists the returned fields, making it clearly distinct from generic siblings like edgar_filings and edgar_financials.

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?

There is no explicit when-to-use or when-not guidance, and no named alternatives among edgar_filings or edgar_financials. Usage is implied by the insider-specific resource and the 25-filing cap, but the agent must infer that this is the right tool for insider Form 4 data rather than general filings.

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