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

Annotations already declare readOnly, idempotent, non-destructive and closed-world, so safety is covered. The description adds genuinely useful context with "(v1alpha)", signalling API instability, and the date-range scoping. It says nothing about the alpha endpoint's limitations, quota behavior, or what the report returns.

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 first sentence is tight and front-loaded with the essential facts. The trailing "Tools revision: d80f65c0." is build metadata that gives the calling agent nothing actionable and dilutes an otherwise efficient definition.

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?

An output schema exists, so return values need no explanation, and annotations cover the safety profile. But for a tool whose whole difficulty is constructing ordered funnel steps, the description leaves the step object completely opaque and never clarifies the property identifier format — the two things an agent must get right to call it successfully.

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 0%, so the description carries the full burden and only partly meets it: "ordered steps" conveys that the steps array is sequence-sensitive, and "over a date range" scopes start_date/end_date. Critically, `steps` is a free-form array of objects (additionalProperties: true) and the description never explains what a step contains (event name, filters, naming), nor what `property` accepts.

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 verb and resource ("Run a GA4 funnel report") and adds the distinguishing trait "ordered steps over a date range," which separates it from ga4_run_report, ga4_run_pivot_report and ga4_run_cohort_report. It stops short of naming those siblings 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?

There is no guidance on when to choose a funnel report over the other GA4 report tools in the sibling list. A reader can infer funnel = sequential step conversion tracking, but no exclusions, prerequisites, or alternative routing are given.

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