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

Annotations declare this is a non-destructive write (readOnlyHint=false, destructiveHint=false), so the safety profile is covered. The description adds nothing beyond 'add' — no duplicate-handling behavior, no per-project limits, and no mention of what happens when the keyword already exists.

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?

One efficient, front-loaded sentence with no filler. It is appropriately sized, though its brevity comes partly from under-specification rather than disciplined editing.

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?

A mutation tool with a nested object, 0% schema description coverage, and no output schema; the description covers only a fraction of what an agent needs. Key creation semantics — required scoping IDs, keyword type taxonomy, and negative keyword support — are absent.

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% and the payload is a nested object with five subfields, so the description carries the burden. It mentions only 'search phrases' (queries) and 'platforms', leaving name, the type enum (buyer_intent/tool/competitor/topic/brand), negativeKeywords, and the required projectId/siteId scoping unexplained.

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 a keyword to monitor') and hints at the payload shape. However, it does not differentiate from closely named siblings like add_article_keywords and add_outreach_keywords, so an agent must infer which keyword store this targets.

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?

The description gives no when-to-use context, no prerequisites, and does not name alternatives such as add_article_keywords or add_outreach_keywords. The 'to monitor' phrase implies lead-monitoring scope but never states it explicitly.

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