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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the read-only, external-data nature is covered by structured fields. The description adds the source of truth (SEC filings S-1/EFFECT/424B), which is useful context, but says nothing about data freshness/lag, rate limits, or pagination behavior for a time-sensitive calendar.

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 sentence that front-loads the verb and resource, then qualifies the two windows. Each clause carries information the agent needs; there is no filler.

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 two-parameter read-only list tool with no output schema, the description covers the purpose and window semantics but omits the result shape (fields returned, pagination) and the limit parameter's meaning. It is adequate but leaves real gaps an agent would have to discover by calling.

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 carry the parameter burden. It partially compensates by defining the 'window' enum values in substantive terms, but the 'limit' parameter (default 20, max 50) is never explained, and the description does not state which window is the default.

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 gives a specific verb ('Get'), a precise resource ('SEC IPO calendar'), and even the underlying filing form types (S-1 / EFFECT / 424B), so the agent knows exactly what data comes back. It does not explicitly differentiate itself from the nearest sibling, get_market_calendar, leaving that distinction to inference.

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 two operating modes are defined inline: 'upcoming (filed/effective, not yet priced)' vs 'recent (already priced)', which tells the agent which window to pick for a given question. There is no explicit when-not-to-use guidance and no pointer to an alternative tool for related needs.

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