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

Annotations already declare readOnlyHint=false, openWorldHint=true, idempotentHint=false, destructiveHint=false, so the mutation and openness profile is covered. The description adds two genuinely useful facts beyond that: the 20-keyword per-call cap and that a rank observation is produced immediately. It stays silent on the non-idempotent consequence (what happens if a keyword is already tracked) and on any credit/quota cost, which for an open-world mutation tool is the missing piece.

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?

A single sentence with no padding, front-loading the operation, the limit, and the immediate effect. Every clause carries 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?

With no output schema, the description must explain what the caller gets back, and 'immediate rank observation' only gestures at it — format, error/partial behaviour, and duplicate handling are unstated. Adequate for a simple two-parameter call, but thin for an open-world mutating tool that consumes quota.

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 100%, so the baseline is 3, but the description contributes a constraint the schema does not: the keywords array is capped at 20 items. That materially changes how an agent batches calls, which is real added value over the schema.

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 (Track) and resource (keywords) scoped to an application, and adds the 20-keyword cap. It does not explicitly contrast with nearby siblings like track_keyword_opportunities or add_competitor, so the discrimination from siblings is left mostly to the name.

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?

Use is implied — you call this to begin tracking keywords for an app — but there is no explicit when/when-not guidance and no mention of the alternative track_keyword_opportunities or of list_keywords for inspecting what is already tracked. An agent must infer the routing.

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