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

Annotations already declare readOnlyHint, idempotentHint and openWorldHint=false, so the safety profile is covered. The description adds real behavioral context beyond that: the implicit filter to non-removed actions, the 30-day window on metrics, and the note that include_in_conversions is an alias of primary_for_goal (Google replaced the old field). It does not mention result limits or pagination.

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?

Front-loaded with the verb and scope, then the parameter guidance. The long field enumeration in the first sentence is dense but each item earns its place given there is no output schema. Two sentences, no 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?

With no output schema, the description compensates by enumerating the returned fields and the flag semantics, and annotations cover the safety profile. Only minor gaps remain (no mention of result volume/pagination or ordering), which are unlikely to block a correct call.

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 coverage is 100%, so both parameters are already documented, including the exact metrics returned by include_metrics. The description's explanation of include_metrics largely restates the schema; its additional value (the primary/include_in_conversions alias) concerns an output field rather than an input parameter. Baseline 3 is appropriate.

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?

Specific verb ('Lists') plus resource ('conversion actions'), with an explicit scope qualifier ('that are not removed') and an enumeration of the fields returned. No sibling covers conversion actions, so the agent can select this tool unambiguously from the get_* list family.

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 conditional guidance for the optional parameter ('Pass include_metrics=true to add...'), which is useful usage context, but it never states when to reach for this tool versus other reporting tools (e.g. get_campaign_setup or performance tools). Usage is implied by the resource name rather than stated.

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