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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the read-only nature is covered. The description adds the account-tier limitation ('Pro and Agency') and the conceptual event of ranking swaps, which is useful. However, it doesn't disclose data recency, pagination, or output characteristics, which would add value beyond the annotations.

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 description is two sentences and front-loads the core function in the first sentence. The phrase 'Pro and Agency.' is terse but informative about availability. It could be slightly more formal, but there is no fluff or redundancy.

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 3-parameter tool with no output schema, the description gives only a high-level idea of what is returned. It doesn't explain how to interpret the clash list or what actions to take from it. The schema covers input mechanics, and the account restriction is noted, but result interpretation and data freshness remain gaps.

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 100%, with detailed parameter descriptions for days (including data lag), site (format and scoping), and limit (bounds and default). The tool description adds no param-specific meaning beyond the general purpose, so it stays at the baseline set by 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?

The description clearly states a diagnostic purpose: detecting cases where multiple of the user's own pages compete for the same search results ('Searches where several of your own pages show up, so Google keeps swapping them and none settles high'). This distinguishes it from broad performance or opportunity tools, though it doesn't explicitly name sibling alternatives or use formal terminology like 'keyword cannibalization'.

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?

There is no guidance on when to use this tool instead of alternatives like find_opportunities, content_decay, or indexing_gaps. The only contextual hint is 'Pro and Agency', which is an account-tier restriction, not a usage condition. No typical scenarios, prerequisites, or exclusions are given.

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