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

With no annotations, the description carries the full burden, and it does well by disclosing that the tool is free, date-stamped, lists only coverage metadata, and explicitly does not reveal report content. It could add ordering or freshness details, but this is a simple read-only list and the disclosed boundaries are useful.

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?

Two tightly written sentences with no filler. The main scope is front-loaded, and the exclusion of report content is stated in the same breath, making the definition quick to parse.

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 one-parameter list tool with no output schema, the description provides the key return concepts: tickers, report counts, brokerage counts, and archive date range. It also sets expectations about what is not included. Exact field names and data freshness are absent but not critical for invocation.

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?

The only parameter, limit, is already fully documented in the schema with a default and max, so schema coverage is 100%. The description adds no extra parameter-level detail, which earns the baseline score of 3.

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?

Description uses a specific verb ('Lists') and a specific resource ('the most-covered tickers') while enumerating output components (report count, brokerage count, archive date range). The explicit statement that it does not reveal report content clearly separates it from content-focused sibling research tools.

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 'preview' framing and the 'does not reveal report content' disclaimer imply this is for coverage-level reconnaissance rather than report content retrieval. However, it never names sibling tools or states explicit conditions such as 'use research_latest for report content,' so guidance remains implied.

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