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

Annotations already declare readOnlyHint, destructiveHint=false, and openWorldHint=false, so the safety profile is covered. The description adds real behavioral value beyond that: it specifies the return contents (per-step user counts, conversion rates, average time between steps) and discloses the anonymous-preview data limitation, which the annotations do not convey.

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?

Three tight sentences: purpose first, then return contents, then access constraints. No filler, and the most important information (what it does) is front-loaded. Slightly dense but nothing wasted.

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 no output schema, the description usefully summarizes the return shape (per-step counts, conversion rates, timing) and flags the anonymous-data limitation. Combined with 100% schema coverage, an agent has enough to invoke it correctly, though the funnel-vs-alternative decision remains implicit.

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 all seven parameters are already documented in the schema, including defaults, ranges, and the enum. The description adds only the illustrative event-chain example, which loosely maps to the 'steps' parameter, so baseline 3 is appropriate.

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?

States a specific analysis verb and resource: 'track where users drop off across a sequence of events', with a concrete example chain (page_view → signup → purchase). This clearly separates it from siblings like analytics_paths or analytics_retention conceptually, though it never names an alternative explicitly.

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?

Provides useful auth/scope guidance ('Anonymous preview is limited to agentanalytics-demo synthetic read-only data; sign in for your own projects'), which tells the agent about data availability. However, it gives no guidance on when to choose a funnel versus paths, retention, or breakdown for a related question.

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