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

With no annotations, the description carries the full behavioral burden and does well: it discloses that filings are parsed per call, that data is near real time, and critically that calls are pay-per-call at $0.002 USDC on Base via x402/MPP with a 402 challenge on unpaid calls. It does not describe default result size, ordering, or pagination behavior, which keeps it from a 5.

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 two compact sentences with zero waste. It front-loads the resource and scope, then adds the essential payment/authentication detail, so every sentence earns its place.

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 simple read tool with one optional parameter and no output schema, the description covers source, freshness, returned fields, and payment mechanics. It leaves minor gaps around limit semantics and result ordering, but an agent has enough to call it 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?

There is only one optional parameter, and schema description coverage is nominally 100%, so the baseline is 3. However, the schema's own description for `limit` is merely "optional," and the tool description adds no meaning about its default value, maximum, or effect on results.

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 states a specific resource and scope: latest insider trades at US public companies from SEC Form 4, with the exact fields returned (who, company, shares, price). This clearly distinguishes it from sibling SEC tools like edgar_company and edgar_search, which cover filings generally rather than insider transactions.

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 by defining the resource as near-real-time insider trades, but it gives no explicit when-to-use guidance, no exclusions, and no comparison to alternatives such as edgar_company or edgar_search. An agent can infer the use case but must decide on its own when this is the right tool.

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