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

Beyond the readOnlyHint and openWorldHint annotations, the description discloses real behavioral nuances: Twitter/Instagram return engagement-weighted scores while LinkedIn/Threads/TikTok rank by post frequency only, times use the supplied IANA timezone defaulting to UTC, and a paid plan is required. This meaningfully informs call expectations.

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?

The description is compact and front-loaded: the main purpose and output shape appear first, followed by platform nuances and practical constraints. Every sentence carries unique information with no filler or repetition.

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?

Given the output schema covers the return structure and annotations confirm read-only behavior, the description provides the remaining necessary context: ranking metric, platform exceptions, timezone defaulting, and the paid-plan requirement. An agent has everything needed to invoke the tool 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?

With 0% schema description coverage, the description compensates by explaining the timezone parameter's format/default and describing platform-specific behavior for the platform enum. The topN parameter is not explicitly explained, but its meaning is inferable from 'ranked' and the schema's integer bounds.

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 gives a precise verb-resource pair: recommend best (dayOfWeek, hour) slots for the user's next post on a platform touch. It specifies the ranking basis, 90-day window, and platform-specific behavior, making the tool's purpose unambiguous and distinct from analytics or scheduling siblings.

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?

The description clearly frames when to use the tool: before a user's next post, for a given platform, with timezone and plan prerequisites. It does not explicitly name alternatives or provide when-not-to-use guidance, but the context is specific enough for an agent to select it correctly.

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