hey_label

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

Annotations already indicate non-read-only, non-destructive, idempotent, and open-world. Description adds return shape {success, error?} but does not elaborate on side effects or error conditions. Value added beyond annotations is moderate.

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?

Two sentences, front-loaded with core action and return, then a helpful tip. No wasted words, highly efficient.

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?

Covers main behavior, return type, and prerequisite. Could briefly explain success/error semantics or note that operation is effective immediately, but overall adequate for a simple tool with three parameters and no output schema.

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 100% with descriptions for all parameters. Description adds cross-reference to hey_list_labels for label_id, providing useful context beyond schema. Baseline 3, plus extra value.

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?

Clearly states 'Add or remove a label on an email thread', specifying the verb and resource. Distinguishes from sibling tool hey_list_labels by directing users to it for discovering label IDs.

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?

Provides explicit guidance to use hey_list_labels to discover label IDs, indicating prerequisite usage. However, does not explicitly exclude alternatives for other actions (e.g., if user wants to list labels instead), but overall context is clear.

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