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

The annotations already declare readOnlyHint=true, so the description need not restate this. The description adds useful context: the data is fetched live from TikTok (implying potential latency or external dependency), and it notes that schedule_post already handles validation internally, which clarifies the tool's role. It does not disclose error behavior or return format, but given the read-only annotation and simple scope, the description adds sufficient behavioral insight without contradiction.

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 exactly two sentences without any filler. The first sentence states the purpose and data source; the second provides actionable usage guidance. It is front-loaded and every word earns its place, making it highly concise and well-structured.

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 simple read-only tool with one parameter and no output schema, the description is complete enough. It explains what data is returned (privacy levels and interaction settings), when to use it, and its relationship to schedule_post. The absence of output schema means the description could specify the exact return shape, but the given information is sufficient for an agent to correctly invoke the tool and understand its purpose.

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 input schema has 100% coverage: the only parameter, profile_id, has a description explaining its source ('from sprkly_list_profiles'). The tool description does not add further semantics beyond that. With the schema already providing clear meaning, a baseline of 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 clearly states the purpose: it fetches the creator's allowed TikTok privacy levels and interaction settings. It uses a specific verb ('fetched') and resource ('privacy levels and interaction settings'), and it distinguishes itself from siblings by focusing on posting options for a specific TikTok profile. The mention of 'live from TikTok' adds clarity about data freshness.

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 explicitly states when NOT to use it ('usually do NOT need this before scheduling') and provides the alternative (sprkly_schedule_post validates the same list itself and returns valid levels on error). It then gives precise conditions for when to call: when the user asks for options or you want to offer a choice. This is exemplary usage guidance.

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