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

The description discloses return structure (summary + up to 50 filings with fields), the default filtering behavior, and what types are included/excluded. This goes well beyond the annotations (readOnlyHint true, destructiveHint false) and provides meaningful context about operational behavior and output limits.

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 well-structured: purpose first, then return format, then filter semantics. It is slightly lengthy, but every sentence carries necessary information—no fluff or redundancy. The clear bullet-like layout of returned fields and filter options improves scannability.

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?

Given there is no output schema, the description fully compensates by listing the exact fields returned and the summary content. It covers purpose, usage, output, and filter semantics, making it complete for an agent to select and invoke the tool correctly in most cases.

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 coverage is 100%, but the description adds significant semantics beyond the schema: it explains the default filing_types behavior, how to override with [], and the explicit allowlist option. It also specifies ticker examples in the schema, and the description reinforces the role of the ticker parameter in context.

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 clearly states the tool's function: 'List indexed SEC filings for a given ticker with a summary header.' It uses a specific verb ('List') and identifies the resource (SEC filings for a ticker), and explicitly distinguishes it from the sibling tool sec_report_search ('For the actual content use sec_report_search instead').

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 provides explicit guidance on when to use this tool ('before searching content') and names the alternative for content search. It also explains the filing_types filter behavior with clear options (omit, [], explicit allowlist), which is practical usage guidance beyond simple when-to-use.

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