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

Annotations already declare destructiveHint=true and readOnlyHint=false, so the mutation risk is covered. The description usefully adds the per-id outcome-verification and the 25-item batch cap, but omits the two-step confirm_id preview/execute workflow, which is the most consequential behavior for a destructive write here.

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?

Extremely dense and front-loaded: purpose first, then SINGLE, then BATCH with the cap, then the outcome note. No filler sentences; every clause earns its place.

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, zero-required-parameter tool with no output schema and a confirm-token flow, the description covers modes and limits but leaves the preview/confirm requirement and the account/profile scoping unexplained in prose.

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 documents the mode-specific parameters (keyword_id, state, items shape) and the batch limit, but says nothing about account_id, profile_id, or the critical confirm_id confirmation token, which the schema alone must carry.

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: updating the state of one or more Sponsored Brands keywords, listing the three valid states. The 'SB' in the name and description distinguishes it from ads_update_sp_keyword_state, though it never names the sibling 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?

Clearly describes the two invocation modes — SINGLE (keyword_id + state) and BATCH (items array, MAX 25) — so the agent knows how to structure a call. It does not, however, state when to prefer one over the other or any prerequisites.

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