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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint, so safety is covered. The description adds behavior beyond that: results are ordered by recency, scoped to US-listed issuers, and include accession numbers. It omits pagination behavior and the hard cap of 20 results, leaving those to the schema.

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 action, scope, and downstream purpose; no filler and no repetition of the schema's enum or defaults.

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 three-parameter list tool with no output schema and no parameter descriptions in the schema, the description covers the identifiers, the ordering, and the key returned field (accession numbers). Missing only edge-case behavior such as invalid tickers or fewer-than-requested results.

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 0%, so the description must compensate, and it does partially: it clarifies that formType takes one of the SEC form types shown in examples, that ticker identifies a US-listed company, and that limit means the N most recent. It does not explain the limit's 1-20 bounds or what happens on an unknown ticker.

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 (List) and resource (recent filings) with scope qualifiers: given form type, N most recent, US-listed company. The parenthetical example form types and the mention of accession numbers make the output shape concrete, though it never contrasts itself with the closest sibling get_filing_section beyond noting the hand-off.

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 phrase 'with accession numbers needed for get_filing_section' implies the correct workflow position (call this first, then fetch a section), which is genuine but implicit guidance. There is no explicit statement of when not to use it, or what to do for non-US-listed companies or non-supported form types.

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