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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false, and openWorldHint=false, so the safety profile needs no restating. The description adds real behavioral value by disclosing that it returns the account's own measured projects plus the latest measurement result, but says nothing about result size, pagination, or empty-account behavior.

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?

Two sentences, both earning their place: the first defines scope and return content, the second front-loads the sequencing instruction. No filler, no restatement of the title or annotations.

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 present, the description compensates by naming the returned fields and the fact that the latest measurement's date and result are included. Combined with the annotations covering the safety profile and zero parameters, an agent has everything needed to call and interpret this tool.

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?

The tool takes zero parameters, so per the baseline there is no parameter semantics burden to carry. The description correctly implies a no-argument call and instead spends its words on scope and return fields.

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 and resource ('Lists the businesses (projects)...') and enumerates exactly what is returned: name, zone, category, plan, and latest measurement date/result. It is clearly distinguishable from every sibling tool (get_competitors, get_mentions, get_pages, get_questions, get_status, get_todos), which all operate on sub-resources of a project.

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?

'Call this first to get the project_id used by the other tools' gives explicit sequencing guidance that tells the agent when this tool must run relative to siblings. It stops short of naming an alternative or a when-not condition, but the sibling set has no overlapping purpose, so no routing ambiguity remains.

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