add_card_label

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

With no annotations, the description discloses key behavior: it adds a single label and preserves existing labels. This covers the main behavioral traits. It does not mention error handling or idempotency, but for a simple mutation it is fairly transparent.

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 extremely concise: two sentences and a bulleted list of arguments. No extraneous information, and the structure is easy to parse. Every sentence serves a purpose.

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 tool's simplicity, the description covers all necessary information: what it does, how to call it, and where to find the label ID. No output schema is present, but the return value is likely implied. The description is complete for effective use.

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 coverage is 0%, so the description must compensate. It provides clear parameter descriptions: card_ref format with a concrete example, and label_id usage referencing list_labels(). This adds meaning beyond the schema's type-only definition.

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 action: 'Add a single label to a card, preserving existing labels.' It specifies the verb (add), the resource (card), and the effect (preserving existing labels), which distinguishes it from the sibling 'remove_card_label'.

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 mentions 'Use list_labels() to find ids,' guiding the agent on how to obtain the label_id parameter. However, it does not explicitly state when to use this tool versus alternatives or provide conditions for avoidance. Given the tool's simplicity, this is acceptable but not exemplary.

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