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

Annotations already declare readOnlyHint=true, openWorldHint=false, and idempotentHint=false, so the description need not cover safety. It adds valuable behavioral context beyond annotations: the output includes per-step conversion, drop-off, timing, an optional breakdown, and comparison deltas expressed in percentage points. The description does not elaborate on rate limits or exactly what the output schema fields mean, but the output schema itself covers return values.

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 dense but front-loaded: it opens with the core purpose, then explains output metrics, comparison deltas, and step definition semantics. Every sentence adds information. It could be slightly more scannable with formatting, but it is efficient for the complexity of the tool.

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 a complex nested definition schema, an output schema, and high schema description coverage, the description is reasonably complete. It explains the funnel concept, references the tracking guide for deeper definition syntax, and mentions saved funnel reuse. It could optionally clarify the required property_id or how filters interact with steps, but the schema covers those fields.

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 83%, so the schema carries most parameter meaning. The description adds useful semantic guidance: it explains that steps are conditions on dimensions (e.g. the name dimension for event names) and that 'compare' runs the same request for an earlier period. It does not add details for preset, date_from, or date_to beyond what the schema already provides.

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 a specific verb+resource ('measure conversion through ordered steps') and names concrete step examples (product view, add to cart, purchase). It clearly distinguishes this funnel tool from sibling query tools like d8a_run_query and d8a_run_paths by describing step-by-step conversion, drop-off, and timing.

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 states when to use the tool ('to measure conversion through ordered steps') and gives prerequisite guidance ('read d8a_get_tracking_guide topic funnel-definition first, or start from a saved funnel's run_input'). It also explains the compare option's purpose. It does not explicitly exclude alternatives or name sibling tools like d8a_run_paths, leaving some routing implicit.

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