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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint and destructiveHint=false, so the safety profile is covered. The description adds genuinely new operational context: free, no wallet, no payment, and no arguments required — useful for cost/auth decisions not present in the 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?

A single efficient sentence with the [FREE] qualifier front-loaded and no redundant filler; every clause 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 zero-param preview with no output schema, the description adequately conveys that the return is a sample of the edgar_bundle shape (filings + company facts). It could say slightly more about what the sample contains, but nothing essential for correct invocation 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?

With zero parameters the baseline is 4. The description confirms 'no arguments needed', which matches the empty schema and removes any doubt about supplying inputs.

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 noun (a sample response for edgar_bundle) and its resource (SEC EDGAR filings + company facts), and explicitly frames it as a preview so an agent can distinguish it from the paid edgar_bundle sibling.

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 clearly states the condition for use — 'see the shape before paying 0.03 USDC' — and that no payment is required, which effectively routes the agent to edgar_bundle for real data. It stops short of an explicit 'use edgar_bundle when you need actual data' sentence, so not a 5.

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