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

Annotations already declare readOnly, idempotent, non-destructive, and closed-world behavior, so the baseline safety picture is covered. The description adds useful scope context: only *public* feeds are returned and each carries a subscribe URL, which tells the agent what to expect.

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?

One tight sentence with the resource and return content front-loaded and the optional filter placed at the end. No wasted words.

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 a rich annotation set, a full output schema, and complete parameter documentation, the description supplies enough to invoke the tool correctly. Minor omissions such as result ordering or whether non-public feeds can ever appear are inconsequential here.

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 single 'field' parameter is documented with examples and a self-referential hint that list_calendars returns the valid fields. The description only adds that filtering is optional, which the schema already conveys via default null and a non-required parameter, so it is a baseline 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?

Names a specific verb and resource: list public calendars (ICS) with their subscription URLs, scoped optionally by field. That is clearly distinct from siblings like fetch, search, and list_upcoming_calendars, though it doesn't name them explicitly.

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 phrase 'optionally for one research field' implies browsing all calendars versus narrowing to one field, but there is no explicit guidance on when to use this versus search or fetch. The agent must infer the use case from the name.

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