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

Beyond the readOnlyHint annotation, the description richly discloses behavior: concise TextContent and matching structuredContent, bounded responses controlled by detail tiers and byte budgets, explicit truncated/omitted metadata, the conditional presence of Reject Path content, and the caveat that results are automated observations not legal advice. This goes well 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 five sentences long, but each earns its place: primary purpose first, then bundle sections, then response control and metadata, then the important Reject Path caveat, then a legal disclaimer. It is dense and well-structured, though slightly longer than strictly necessary.

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 that an output schema exists, the description does not need to explain return values. It covers availability (completed/completed-limited), content sections, bounded response mechanics, truncation metadata, Reject Path conditions, and legal disclaimers. A minor gap is the lack of error behavior for invalid or in-progress scanIds, but the sibling get_scan_status likely covers that workflow.

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%, so the baseline is 3. The description adds meaning by explaining that 'Detail tiers and byte budgets control the bounded response' and that metadata is returned to indicate truncation, which clarifies how the detail, maxBytes, maxFindings, and maxPreConsentRows parameters interact. It does not describe each parameter individually, but it adds useful context beyond the schema.

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 states a specific verb and resource: 'Returns the completed or completed-limited CertScore evidence bundle for a stable scanId.' It further enumerates the bundle's sections, making the tool's function unambiguous and clearly distinct from the sibling tools (status checking and site scanning).

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 clear context for use: it requires a 'stable scanId' and is only for 'completed or completed-limited' scans, implying it should be called after a scan reaches completion. However, it does not explicitly name the sibling tools or provide when-not-to-use exclusions, relying on inference rather than direct alternatives.

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