Contract Testing: Add Label to Pacticipant

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

Annotations already declare readOnlyHint=false, idempotentHint=false, destructiveHint=false, and openWorldHint=false, so the safety profile is covered. The description adds nothing beyond that: it does not say what happens if the label already exists (relevant given idempotentHint=false implies possible error), whether the label is created on the fly, or what a failure looks like.

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 opening sentence is front-loaded and efficient, but the parameter section duplicates the input schema word for word and the 'Toolset: Labels' line adds little for an invoking agent. It is short but partially redundant rather than dense with value.

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 not be explained, and the tool is simple with two required string parameters. Still, for a non-idempotent mutation it omits error behavior and preconditions, leaving meaningful gaps for an agent deciding whether to call it.

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 100%, so both parameters are already documented in the schema. The description's parameter list merely restates the schema text verbatim ('Name of the pacticipant', 'Name of the label') without adding format, constraints, or examples, so the baseline of 3 applies.

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 verb and resource ('Apply a label to a pacticipant'), which is unmistakable and clearly distinct from siblings like remove_label_from_pacticipant or get_pacticipant_label by name. It stops short of explicitly naming those siblings as alternatives, so it is clear but not fully differentiated within the description text.

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?

There is no when-to-use guidance, no mention of prerequisites (does the pacticipant or label need to exist first?), and no reference to the inverse sibling remove_label_from_pacticipant. The agent must infer context entirely from the tool name.

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