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

Annotations already flag destructiveHint=true and openWorldHint=true, but the description adds the asymmetry that makes the confirm flow intelligible: additions widen reach and need confirmation, removals execute immediately. It does not disclose the 25-item cap, what happens on partial failure, or what dry_run returns, but it clearly exceeds the annotation baseline.

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?

Two tight sentences with the action and the target front-loaded, followed by the one behavioral distinction an agent must know. Nothing is redundant with the schema and nothing could be cut without losing meaning.

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?

For a destructive six-parameter mutation tool with no output schema, the description covers the core add/remove/confirm model but omits the maxItems limit, dry_run's role, and any statement about return values or validation failures. Adequate, but an agent still has to read the schema to call it safely.

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 67%, with remove, account, confirm, and dry_run documented in the schema. The description adds real meaning by explaining that confirm applies to the add path specifically, but leaves the add and asset_group_id parameters without any narrative definition. 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?

States a specific verb pair (add/remove) and resource (search themes on a Performance Max asset group), and briefly defines what a search theme is. An agent can distinguish it from siblings like google_ads_pmax_audience_signal or google_ads_add_keywords, though no sibling is named 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?

The description implies the two operating modes (adding vs removing) and notes that adding requires confirmation while removing does not, which shapes the call sequence. It does not say when to prefer this over related tools such as pmax_audience_signal or pmax_asset_group, nor when adding themes is inappropriate.

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