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

Annotations already declare readOnlyHint=true and destructiveHint=false, so safety is covered. The description adds valuable behavioral context by noting it 'flags the warning signs on upfront-fee credit repair and advertised-certainty lending' and highlights the common single-bureau reporting gap. This goes beyond the structured annotations, giving the agent expectations about the tool's output content and its cautionary role.

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 three sentences with zero filler. The first sentence states the core purpose and grouping; the second highlights the most critical reporting detail; the third gives the usage tip and the Canada-specific warning. Everything is front-loaded and every clause 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 tool with one optional parameter, an output schema, and read-only annotations, the description is complete. It covers what is listed, how it is grouped, the key reporting nuance, the warning signs included, and explicitly when to use it. No critical information needed to call the tool correctly 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?

The only parameter, 'tier', is filled by the schema with an enum and a clear description ('Filter to one credibility tier. Omit for all.'). The tool description itself does not mention the parameter or add any extra nuance, but schema coverage is 100%, so the baseline is 3. The description adds no semantics beyond what the schema already provides.

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 opens with a specific statement of what the tool provides: 'Secured cards, credit-builder loans, and rebuild products available in Canada, grouped by how established they are, with which bureau each reports to.' It clearly differentiates from siblings via the closing note: 'Use this instead of recalling product names, which for Canada are frequently confused with United States products.' This makes the tool's scope and its differentiation unambiguous.

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 gives explicit advice to 'use this instead of recalling product names,' which is a clear directive. It also adds context about the Canada vs. US confusion, which helps an agent decide when this tool is relevant. However, it does not explicitly state when NOT to use it or mention any sibling tools as alternatives, so it stops short of full guidance.

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