label_add_at

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 that a label is added, but does not disclose side effects such as whether an existing label at the same range is overwritten, whether a label track is created, or whether the new label becomes selected. This leaves the agent to infer important behavioral details.

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 very concise: one clear purpose sentence followed by a compact argument list. Every line contributes either the core action or parameter semantics, and it is front-loaded with the most important information.

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 tool with only three parameters, the description covers the action and parameter meanings well. However, it lacks usage guidance and behavioral side effects, and is situated among many label-related siblings. This makes it minimally viable but not fully complete for an agent needing to select and invoke it reliably.

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 0%, so the description must compensate. It does so by adding units ('in seconds') for start and end and clarifying the default behavior of text ('Default: empty'). This is valuable beyond the raw schema. It stops short of specifying constraints like end > start or acceptable value ranges, but it meaningfully aids parameter understanding.

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 states a specific action, 'Add a label at a specific time range,' which clearly identifies the verb and resource. It also signals that the label is positioned by explicit time bounds, distinguishing it from label_add, which likely uses the current selection. However, it does not explicitly contrast it with nearby siblings like label_add_batch or label_regular_intervals, so sibling differentiation is incomplete.

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 gives no guidance about when to choose this tool over alternatives such as label_add, label_add_batch, or label_regular_intervals. It only implies usage through the action statement; there are no explicit when-to-use or when-not-to-use conditions.

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