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

Annotations already declare readOnlyHint=true and idempotentHint=true, which cover the safety profile. The description adds minimal behavioral context beyond that ('generated' report), but does not disclose edge-case behaviors like not-found errors or authorization requirements. Since the description is consistent with annotations and provides some value, a mid-range score is appropriate.

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 a single, front-loaded sentence that conveys the essential information with zero wasted words. It is perfectly concise for the tool's simplicity.

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?

Given the tool's low complexity (one parameter), the presence of an output schema, and strong annotations, the description sufficiently covers the necessary information. It does not explain return values, but that is not required since an output schema exists. Only a minor gap: no mention of error scenarios, but the overall context is complete.

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 input schema has 100% coverage with the parameter report_id described as 'UUID of the report to fetch.' The description's 'by ID' simply restates this, adding no extra meaning beyond the schema. Baseline of 3 is appropriate given the high schema coverage.

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 'Fetch one generated report by ID' uses the specific verb 'fetch' with a clear resource ('one generated report') and scope ('by ID'). It distinguishes itself from sibling tools like list_reports (which lists multiple) and generate_report (which creates), leaving no ambiguity about its function.

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 usage context: use this when you have a specific report ID and need that single report. However, it does not explicitly mention alternatives or exclusions (e.g., 'For listing reports, use list_reports'). The context is clear but not explicitly contrasted with other tools, so it stays at implied usage.

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