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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint=false and destructiveHint=false, so safety is covered. The description adds real content beyond that by naming what the payload holds, including a staleness/change indicator — the one behavioral trait (records can mutate after filing) that annotations would not reveal.

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 front-loaded sentence with the scope first and the field inventory second; no filler, no restatement of the title or annotations.

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?

With no output schema, the description must convey the return shape and does so at a summary level. It leaves open how records are ordered, whether the listing is paginated or bounded, and what "changed since" is measured against — minor but real gaps for a zero-parameter tool that returns everything.

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?

Zero parameters, so there is nothing to disambiguate and the baseline of 4 applies. The description correctly implies an unfiltered full listing rather than suggesting filters that do not exist.

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?

"Every filed return" states the resource and the all-records scope, and the clause after the colon enumerates what each record carries (period, filed/paid amounts, change flag). The word "Every" implicitly contrasts with the single-record sibling tax_get_filing, though that sibling is never named.

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?

Usage is only implied: this is the bulk/list view of filings, so an agent can infer it should call tax_get_filing for one record or tax_liability/tax_return for computed figures. No explicit when-to-use, when-not, or alternative is stated.

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