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

Annotations already declare readOnlyHint=true, so safety is covered. The description adds behavioral context that the calendar includes both upcoming and recent IPOs for the given date range, but does not describe return format, pagination, or other potential behaviors. This meets the baseline for a read-only tool with annotation coverage, with modest additional value.

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 two sentences, front-loaded with the core purpose, and includes only relevant information (the REST endpoint). There is no fluff or redundancy, and every word earns its place.

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 read-only tool with two required parameters, well-defined schema, and read-only annotation, the description is mostly complete. However, since there is no output schema, a brief note about the response shape (e.g., array of IPO events) would enhance completeness. The lack of such detail is a minor gap.

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 100%, with both 'from' and 'to' clearly documented as required start and end dates with a format pattern. The description merely says 'date range' without adding any semantic detail beyond what the schema already provides. Baseline 3 is appropriate when the schema does the heavy lifting.

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 it provides an IPO calendar for a date range, including upcoming and recent initial public offerings. It specifies the resource (IPO calendar) and scope, and is distinct from sibling tools like earnings calendar or market news. The inclusion of the Finnhub REST endpoint further clarifies the exact functionality.

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 description implies when to use this tool: whenever IPO data for a specific date range is needed. It gives clear context about what the tool covers (upcoming and recent IPOs) but does not explicitly mention alternatives or when not to use it. This qualifies as 'clear context, no exclusions'.

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