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

The description goes well beyond the readOnlyHint annotation by explaining how routes are constructed: consecutive repeats are collapsed, only the first 10 steps define a route, and visitor identity rotates daily so a route describes a group, not a person. These are critical behavioral nuances not expressed in the annotations or schema.

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?

Every sentence earns its place: core definition, usage discrimination, step syntax, route construction rules, filter guidance, and data identity caveat. The description is dense but not bloated, and the core purpose is front-loaded.

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 complexity and the presence of an output schema, the description covers everything an agent needs to correctly select and invoke it: when to use it, how steps are represented, route truncation behavior, the daily identity rotation, and filter behavior. No important gap remains.

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 description coverage is 100%, so the baseline is 3. The description adds meaningful semantics for the contains parameter, explaining it filters routes to those including a given path or event and suggesting how to use it for comparison. It also clarifies the step syntax that applies to contains and route interpretation.

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 and informative definition: routes visitors actually take, grouped into identical sequences and counted, busiest first. It explicitly contrasts itself with the sibling tool 'funnel', making its unique purpose immediately clear.

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?

It explicitly tells the agent when to use this tool: 'Use this when you do NOT already know the steps', and names the alternative funnel with its distinguishing condition. It also gives operational guidance on using the contains filter with and without to compare converting visitors.

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