update_label

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

Annotations are absent, so the description carries the full burden of behavioral disclosure. It only states that an existing label is updated, but fails to explain critical behaviors such as whether omitted optional parameters are left unchanged or reset, whether system labels are updatable, or whether the operation is idempotent. No behavioral traits beyond the tool's literal meaning are disclosed.

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 a single, front-loaded sentence with no filler or wasted words. It is appropriately concise, though it leans toward under-specification; a longer sentence with a few behavioral details would still be concise and would improve the definition.

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 a 100%-covered schema and an output schema present, the tool is minimally callable: id is required and optional fields are documented. However, the description omits important contextual information about partial-update semantics (what null values mean), system-label limitations, and the relationship to sibling label tools. These gaps prevent the definition from being fully complete for an agent choosing and invoking this tool correctly.

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 the baseline is 3. The description adds no parameter-level meaning, but the schema already documents each parameter clearly (e.g., 'New name for the label', 'labelShow, labelShowIfUnread, or labelHide'). The description neither improves nor degrades the parameter understanding provided by the schema.

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 'Update an existing Gmail label' uses a specific verb ('update') and resource ('existing Gmail label'), making the tool's purpose immediately clear and distinguishing it from sibling tools like create_label and delete_label. No ambiguity remains about the operation being performed.

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?

No guidance is given about when to use this tool versus alternatives such as create_label, get_or_create_label, or delete_label. The description does not mention exclusions, prerequisites, or when to prefer another sibling tool, leaving the agent to infer usage from the name and schema alone.

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