Add negative keywords

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

Annotations already declare readOnlyHint=false and destructiveHint=false, but the description adds the material detail that this mutates the live account and that a confirmation token is needed past a bulk threshold — context that isn't in the annotations or schema. It doesn't say whether additions can be reverted or how failures are reported, which keeps it from a 5.

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?

The effect and the live-account warning are front-loaded in one sentence, followed by tight per-parameter notes with no filler. The line-wrapped parameter block is slightly awkward to scan but nothing is redundant.

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 5-parameter mutation tool with annotations and an output schema, the description covers the critical hazards (live changes, bulk confirmation) and the two ambiguous fields. The remaining gap — undocumented ad_account_id and keywords item format — is minor but real given 0% schema coverage.

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 0%, so the description must carry parameter meaning; it does explain parent_id's three levels (ad group / campaign / ad account) and match_type's values and default. However, ad_account_id is never mentioned and the expected shape of the keywords array is left implicit, so it only partially compensates.

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 negative keywords') plus the observable effect ('so ads don't show on those searches'), which cleanly separates it from pinterest_ads_create_keywords and the archive/list keyword siblings. The scope sentence ('Changes the live account') further pins down what kind of operation it is.

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 clear context for when this applies (excluding searches) and a concrete prerequisite: bulk requests above PINTEREST_ADS_BULK_THRESHOLD require confirm='APPLY'. It does not explicitly name an alternative tool or say when not to use it (e.g. vs pinterest_ads_create_keywords), so it stops short of full routing guidance.

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