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 adds valuable context beyond that: the Indie-plan prerequisite and trial-count consumption, plus a detailed inventory of what is returned (live stats, top rows, AI insight), which helps the agent anticipate cost and output.

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?

Front-loaded with the core purpose and scope, followed by a dense but useful enumeration of return contents. It is a single long sentence, but each clause (stats categories, top rows, AI insight, plan requirement) carries distinct information, with little true filler.

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?

There is no output schema, so the description must carry return-value burden, and it does so thoroughly: it lists the stat categories, the top gap/threat/lead rows with metrics, and the optional AI insight contents. Combined with the plan prerequisite and the single fully-documented parameter, an agent has everything needed to call it correctly.

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%, and the schema already documents app_id richly (own app UUID, not a store id, not a competitor id). The description's 'one of your own apps' is consistent but adds no syntax or format detail beyond the schema, so baseline 3 is appropriate.

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 states a specific resource and scope: 'The full competitive keyword picture for one of your own apps vs every tracked competitor, in one call,' then enumerates the concrete contents (gaps, winnable gaps, climbers, leads, top rows, AI insight). It distinguishes itself from narrower siblings like sonar_competitor_keywords/sonar_analyze_competitors by framing itself as the aggregate 'full picture' delivered in a single call.

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?

'Read this before deciding which keywords to target next' gives a clear usage context, and the plan gating ('Requires an Indie plan') sets a precondition. However, it never explicitly names the alternatives (e.g. sonar_competitor_keywords for a narrower slice) or states when NOT to use it, so it stops short of explicit exclusion guidance.

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