get_today_sleep_data

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It states the tool returns a dictionary but doesn't describe what that contains (e.g., sleep stages, duration, quality), whether it's a read-only operation, potential errors, or data freshness. This is inadequate for a tool with zero annotation coverage, as it lacks essential behavioral context.

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 brief (two sentences) but not optimally structured. The first sentence states the purpose clearly, but the second ('Returns: Dictionary containing sleep data for today') is redundant with the first and could be integrated more efficiently. It's concise but could be improved with better flow.

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 no annotations, no output schema, and a simple tool with 0 parameters, the description is incomplete. It doesn't explain the return value's structure (e.g., keys in the dictionary), error conditions, or how it differs from siblings. For a data-fetching tool, more context on the output is needed to be fully helpful.

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 0 parameters with 100% coverage, so no parameter documentation is needed. The description correctly omits parameter details, avoiding redundancy. A baseline of 4 is appropriate since the schema fully handles parameters, and the description doesn't add unnecessary information.

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 tool's purpose: 'Get sleep data for today.' It specifies the verb ('Get'), resource ('sleep data'), and temporal scope ('today'), making it unambiguous. However, it doesn't explicitly differentiate from its sibling 'get_sleep_data' (which likely lacks the 'today' filter), missing full sibling distinction for a perfect score.

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 provides no guidance on when to use this tool versus alternatives. It doesn't mention sibling tools like 'get_sleep_data' (for broader date ranges) or 'get_today_readiness_data' (for other today-specific metrics), leaving the agent to infer usage context without explicit direction.

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