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

Annotations already declare readOnlyHint, destructiveHint=false and openWorldHint=false, so repeating 'Read-only' earns nothing. The description does add real behavioral context absent from structured fields: the payload composition, the fact that the mapped page's current title/meta is included alongside the proposal, and notably that the active apply's apply_id can be used to undo it — useful cross-tool state disclosure.

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?

Effectively one dense sentence, front-loaded with the resource ('One cluster in full:') before the payload list. The enumeration is long but each item is information the agent needs given no output schema; only the redundant 'Read-only.' trailer is dead weight.

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 carries full responsibility for describing returns and does so thoroughly, including relational context (proposal vs. live page vs. active apply). For a two-parameter read-only tool, an agent has everything needed to call it and interpret results.

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% for both parameters, and the description adds nothing about cluster_id or the keywords_limit truncation behavior. Baseline 3 applies since the schema does all parameter work.

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?

'One cluster in full' names a specific resource and scope, then enumerates exactly what comes back (keywords, page proposal with reasoning, mapped page, ranking domains, active apply). It is clearly distinct from a listing tool, though it never names a sibling explicitly to route the agent.

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 only implied: fetch a single cluster by id, where the id comes from seo_list_clusters or seo_growth_points. There is no explicit when-to-use vs when-not guidance (e.g., use seo_list_clusters for a bulk overview, this for one cluster's detail), and no prerequisites are stated.

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