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

Annotations already declare readOnly, idempotent, non-destructive, closed-world, so the safety profile is covered. The description still adds real interpretation context the annotations cannot: null means outside the top 20, null pieceId means the ranking page isn't a Kooga article, and a one-or-two place move is noise rather than signal.

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 front-loaded sentence with the resource stated first and the field glossary after; the closing caution about noise earns its place. It is dense but every clause carries information, not padding.

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 needn't be spelled out, yet the description goes further and pre-decodes the non-obvious field names (`pieceId`, `odds`, `previous`) and their null semantics. For a two-parameter read tool this is close to complete, with only the missing sibling routing keeping it from the top.

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%, so the two parameters are fully documented in structured form and this is the baseline case. The description adds nothing parameter-specific — no explanation of what limit ordering means in practice or when workspaceId is required beyond what the schema already says.

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?

Opens with a specific verb+resource ('Google positions for the keywords the merchant tracks') and enumerates what each returned field means. It implicitly separates itself from AI-visibility tooling, but never names a sibling such as readCompetitors or readOpportunities, so the differentiation is only partial.

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?

Usage is implied rather than stated — the agent can infer 'call this to see where tracked keywords rank'. The one genuine routing cue is the negative one ('These are Google rankings, NOT AI visibility'), which helps exclude a misread but gives no when-to-use/when-not conditions or named alternatives.

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