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

Annotations already declare readOnlyHint=true and idempotentHint=true, so the safety profile is covered. The description adds valuable context: data source (IRCC open data), licensing (Open Government Licence - Canada), rounding behavior (nearest 5), and citation requirements. This goes beyond what annotations provide.

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 compact and front-loaded with the core purpose. The citation URL is somewhat long but serves a functional purpose. Every sentence adds value: what data, from where, under what license, and how to cite.

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 zero-parameter read-only tool with an output schema, the description is quite complete. It covers data source, licensing, rounding, and citation. The only minor gap is not describing the exact output structure, but the output schema presumably handles that.

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 tool has zero parameters, so the schema is trivially complete. The description compensates by explaining what data will be returned (monthly counts, yearly totals, top countries of birth), which is the relevant semantic content for a no-parameter tool.

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 the tool provides official IRCC statistics on new Canadian citizens, with specific data types (monthly counts, yearly totals, top countries of birth). It distinguishes itself from sibling tools by focusing on citizenship statistics rather than study guides, practice questions, or journey stats.

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 this is a reference/statistics tool for citizenship data, distinct from the study/test tools in the sibling list. It doesn't explicitly state when not to use it, but the context of official statistics makes its use case clear. It also provides citation instructions, which is a form of usage guidance.

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