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

Annotations already cover the safety profile (readOnly, idempotent, openWorld, non-destructive), so the description rightly spends its space on behavior annotations can't express: age/duration filters only match games with published metadata and never infer a fit, and results may require an email for access. That is real, non-obvious disclosure beyond the structured data.

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 purpose, then the two filtering caveats, then the access caveat; every sentence carries information and none is filler. Slightly dense (em dashes and long clauses) but proportionate to the tool's complexity.

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 an output schema present, return values need no explanation, and the description covers the two genuinely surprising behaviors (metadata-strict filtering, mixed free/email access). The remaining gap is guidance on the skill/audience/limit parameters, which is a minor omission for a no-required-param search 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?

Schema coverage is 0% with six parameters, so the description must carry the load. It explains age and max_duration_minutes matching semantics well and hints at query via examples, but says nothing about skill, audience, or limit — three of the six parameters remain undocumented anywhere.

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+resource ('Finds interactive mindfulness games') plus the source library, and the phrase 'interactive mindfulness games' cleanly distinguishes it from siblings like find_guided_practices and search_mindfulness_resources. An agent can pick this tool 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 concrete usage examples ('a grounding game for a 9-year-old', 'a short breathing game under 5 minutes') that show what the tool is good for, and explains the match semantics for age and duration. It does not explicitly name an alternative tool or state when NOT to use this one, so it stops short of full routing guidance.

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