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

Annotations already indicate readOnlyHint=true, destructiveHint=false, and idempotentHint=true, which are consistent with the description's 'List' verb. The description adds no extra behavioral context (e.g., pagination, time range default, rate limits). Since annotations cover the core safety profile, the description is adequate but not enriched.

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?

A single sentence that is front-loaded with the core action ('List recent visitor sessions') and efficiently lists key filters. No unnecessary words or redundancy.

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 8 optional parameters and an output schema, the description covers the basic purpose and filter options. However, it omits important context like the default time range for 'recent', pagination behavior (limit/offset), and how multiple filters interact. The output schema exists, so return structure is documented elsewhere, but the description could be more helpful for an agent.

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% with clear parameter descriptions. The description lists filter names (URL, country, device, etc.), but does not add meaning beyond what the schema already provides (e.g., parameter types, defaults, constraints). Baseline 3 is appropriate as the schema does the heavy lifting.

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 uses the verb 'List' and specifies the resource as 'recent visitor sessions'. It explicitly names several filters (URL, country, device, duration, friction, rage clicks), which helps distinguish this tool from siblings like get_session_detail or get_live_visitors. However, it does not explicitly differentiate from other listing tools like get_campaign_sessions, leaving some ambiguity.

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 when needing to list sessions with filters, but provides no explicit guidance on when to use this tool versus alternatives (e.g., get_session_detail for single session, get_live_visitors for real-time). No when-to-use or when-not-to-use statements are present.

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