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

Annotations only declare readOnlyHint=true, so the description carries the real burden and delivers: whole-USD disclosed amounts, the crucial semantic that total_offering_amount is a ceiling rather than money raised, the ~1-quarter posting lag that makes short windows empty by construction, the limit default/cap, public-domain FREE source, and that caveats travel in tool_notes. This is materially more than the annotations supply.

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?

Front-loaded with purpose, scope, and return shape before the caveats, and nearly every sentence earns its place. Minor redundancy: the limit default/cap and the quarterly-lag caveat are restated from the schema descriptions.

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 compensates by naming the return shape ({summary, count, days, industry, offerings}) and flagging that caveats ride in tool_notes. Nothing an agent needs to invoke the tool correctly or interpret the empty-window case 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?

Schema coverage is 100%, and the description largely echoes what the schema already states for `days` (quarterly lag) and `limit` (default 50, cap 200). The `industry` filter is named but not embellished. Baseline 3 is appropriate when the schema does the parameter documentation.

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 resource (SEC Form D private-placement filings) with its exact source data set, ordering ('newest first'), and optional scoping axes (industry group, trailing filing-date window). An agent can distinguish this from generic filing search siblings like ol_filing_search without opening the schema.

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 establishes usage context (recent filings from the quarterly data set, optional N-day window) and warns that a short window is empty by construction, which guides correct invocation. However, it never names alternatives (e.g., ol_filing_search for older or non-Form-D filings) or states when NOT to use this tool, leaving sibling routing to inference.

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