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

Annotations declare non-read-only, non-idempotent, non-destructive, but the description adds real behavioral context the annotations lack: bulk application of a default match_type to items without their own suffix, and confirm=false producing a dry-run. It does not discuss auth requirements or rate limits, but the dry-run and mixed-set-in-one-call behavior are valuable disclosures.

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 purpose, then usage routing, then parameter syntax. Dense and information-rich, though the all-caps emphasis and repeated restatement of the suffix syntax add slight length without new information.

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?

An output schema exists, so return values need no explanation, and annotations cover the safety profile. The description covers purpose, alternatives, dry-run, and match-type semantics; only edge cases like duplicate-keyword handling or error behavior are unaddressed.

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?

With 0% schema description coverage, the description must carry the load and largely does: it defines match_type values (PHRASE | EXACT | BROAD), the per-keyword '|EXACT' suffix override syntax with a concrete example, and confirm=false as dry-run. customer_id and ad_group_id are left implicit, which is a minor gap.

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 (ADD POSITIVE KEYWORDS to a Google Ads ad group), including bulk scope, and explicitly distinguishes itself from the negative-keyword tool. An agent can route correctly without opening either schema.

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?

Gives explicit when-not guidance (add_negative_keyword is only for BLOCKING traffic), names manage_keywords for pause/enable/re-bid of existing keywords, and describes the move workflow (add on target, remove from old). Clear alternatives and triggers throughout.

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