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

Annotations already declare readOnly, idempotent, non-destructive, closed-world behavior, so the safety profile is covered. The description adds genuine value with 'Needs people:read', an auth requirement not encoded in annotations, and flags PII sensitivity by noting that goal values are whatever the website sends, emails included. It does not disclose default period behavior, pagination, or what an empty result means.

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?

At roughly 45 words it wastes little space, but the structure is poor: four parallel sentence fragments followed by a confusingly worded rationale ('Personal because a goal's values are whatever your website sends, emails included'). The most actionable fact, the permission requirement, is buried at the end rather than 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?

With seven parameters, three result modes, and no output schema, the description should explain how the view parameter selects among the three result shapes it names; it never makes that linkage explicit. Date handling, filters, and goal scoping are left entirely to the schema, which is acceptable but leaves the definition only minimally sufficient for a multi-mode analytics tool.

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 schema already documents period, from/to, filters, goal, and the view enum. The description reinforces that results vary by view but adds no syntax, default, or precedence detail beyond the schema, which is the expected baseline when the schema carries the load.

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 lists what the goal is about (completions over time, top traffic sources and pages, values sent with a goal), which hints at the three result shapes. But it is written as disconnected noun fragments with no verb or resource framing, so an agent cannot tell that this is a retrieval tool that returns one of three views. It also doesn't distinguish itself from list_goals, which is the natural companion for resolving goal names.

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 explicit when-to-use guidance, no statement of when to prefer a sibling such as get_timeseries or get_breakdown, and no indication that list_goals should be called first to obtain a goal name. The only conditional information is the access-scope note, which is a prerequisite rather than usage guidance.

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