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

Annotations already declare readOnlyHint=false, destructiveHint=true, openWorldHint=true, so the write/irreversibility profile is covered. The description adds meaningful behavior beyond the annotations: batch is capped at 25 items and the result is reported per-ID, which tells the agent partial failures are possible. It does not explain the confirm_id two-step write flow, though the schema does.

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 core action, followed by terse SINGLE/BATCH usage lines and the cap. Every clause earns its place; no filler despite covering multiple modes.

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 per-ID verification note partially compensates by signaling result granularity. Missing pieces (the confirm_id two-step flow, profile_id meaning) are documented in the schema rather than the description, so the definition is adequate but not fully self-contained for a destructive 6-param 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 coverage is 50%. The description clarifies how keyword_id, state, and items compose for single vs. batch calls, which adds value. It says nothing about account_id, profile_id, or the confirm_id confirmation token, so the remaining half of parameters are covered only by schema descriptions (or not at all for profile_id).

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+resource (update keyword state) and names the exact valid values (ENABLED/PAUSED), and distinguishes the single-item form from the batch form. An agent can tell this apart from the sibling ads_update_sp_keyword_bid, which changes bids rather than state.

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?

Clearly explains the two invocation modes (single: keyword_id + state; batch: items array) and the batch cap of 25 per call, which is real operational guidance. It doesn't explicitly name alternatives or state when NOT to use it, but the mode framing gives clear selection context.

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