GA4 key events

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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false and openWorldHint=true, so the safety profile is fully covered and the description's 'Read only' adds nothing. The only behavioral value added is that key events carry a deletable flag, hinting at mutation routes elsewhere, but there is no word on pagination, scoping, or auth beyond what the schema states.

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?

A single compact sentence, front-loaded with the resource and followed by the field list, then the read-only qualifier. Efficient, though the parenthetical and trailing list make it slightly dense.

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 carries the burden of describing returns, and it does list the returned attributes (event name, counting method, default value, custom/deletable flags). For a simple read-only tool with two optional params this is close to sufficient; only collection-level details like ordering or result shape are missing.

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% and both parameters (client_id, property_id) are documented in-schema with defaults and fallback semantics. The description adds no parameter meaning at all, so the baseline 3 applies.

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?

Names a specific resource (GA4 key events, formerly conversions) and enumerates the fields it surfaces, with 'Read only' distinguishing it from write-oriented siblings such as ga4_plan_key_event_create. It stops short of naming an alternative explicitly, but an agent can tell this is the read counterpart to the create-plan tool.

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?

The description gives no when-to-use guidance, no mention of prerequisites (client_id needed when several clients are registered), and does not route the agent to or away from any sibling. 'Read only' is the only usage signal, and it merely restates the annotation.

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