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

Annotations already declare readOnlyHint=false and openWorldHint=true, but the description adds genuinely new behavioral context: the WRITE nature, the 'at most one iOS + one Android app per product' constraint, the Indie plan requirement, and the auth/scope requirements. This is exactly the kind of value structured fields cannot carry.

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?

Three tight sentences, front-loaded with the critical 'WRITE tool' classification, followed by the constraint, the alternative, and the prerequisites. No filler; every sentence earns its place.

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 write tool with 100% schema coverage, no output schema needed, and annotations covering safety, the description is complete: purpose, constraints, alternative, plan, and auth requirements are all present. 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%, so all four parameters (including the store_id formats and product UUID semantics) are already fully documented in the schema. The description adds no syntax or format detail beyond that, so the 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?

States a specific verb (links) and resource (the second-store version of an existing Sonar product), and explicitly contrasts it with the sibling sonar_create_product used for brand-new apps. An agent can distinguish this from the other tracking tools without opening any schema.

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?

Gives explicit when-to-use (adding the second store's version), when-not-to-use (brand-new app → sonar_create_product), and the preconditions (Indie plan, authorized account or write-scoped API key). Nothing is left to inference.

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