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

Annotations already declare readOnlyHint/openWorldHint/destructiveHint, so safety is covered. The description adds non-obvious behavior: the data is LIVE/current (not cached/aggregated) and deliberately excludes performance metrics, which is real value beyond the annotations. It does not, however, mention pagination or scope limits of the returned set.

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 front-loaded sentences, no filler. The scope/boundary statement is stated first and the redirect to the alternative second, so no token is wasted.

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 read-only list tool with no output schema, the description does convey the essential return content (bid + state) and the absence of performance fields. However, it leaves the meaning of three of four filter parameters unexplained, which matters for correctly narrowing the query.

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 only 25% — only account_id is documented, and profile_id, ad_group_id, and campaign_id are bare strings. The description says nothing about what these filters do or whether they combine, so it fails to compensate for the coverage gap that the low-coverage rule requires.

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 and resource (list live SP keywords) plus the exact scope: current bid and state. An agent can distinguish it from ads_list_sb_keywords, ads_list_sp_targets, and the create/update siblings from the name and first clause alone.

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?

Explicitly states when to use it ('per agire o verificare' — for bidding/acting or verifying) and when not to (no performance data), naming the concrete alternative `execute_sql` on `fact_keyword_daily` for spend/sales/ACoS/wasted-keyword questions. This is a textbook when/when-not/alternative routing.

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