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

Annotations already declare read-only, non-destructive, closed-world behavior. The description adds meaningful behavioral context about how steps are evaluated (page, event, scroll threshold), how modes differ, and that compare_previous runs the same funnel over the previous period. It stops short of describing return structure or authentication/rate-limit behavior.

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 compact and front-loaded: it states the tool's purpose first, then step semantics, then mode options and compare_previous. Every sentence adds actionable information without repetition or filler.

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?

For a 10-parameter analytics tool with no output schema, the description covers the essential behavior: what the funnel computes, valid step types, mode differences, and previous-period comparison. Annotations and schema cover safety and most parameter details. Some minor return-shape details are omitted, but they are not critical for correct invocation.

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?

With 70% schema description coverage, the description fills important gaps: it explains mode enum meanings, step types and wildcard support, scroll threshold semantics, and compare_previous behavior. Other parameters such as filters, period, and timezone are already documented in the schema, so the description appropriately avoids restating them.

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 clearly states a specific analysis: 'Conversion funnel: how many sessions completed each step.' It defines what a step is and outlines modes, so the agent knows the resource and operation. However, it does not explicitly distinguish this tool from similar siblings such as get_journeys or get_retention.

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?

Usage is implied by the funnel description and the explanation of ordered/strict/flexible modes. There is no explicit guidance on when to choose run_funnel over sibling tools, nor any stated prerequisites or exclusions.

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