unlabel_thread

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

Beyond the annotations (idempotent, non-destructive, open world), the description discloses a hard operational limit ('at most 100 items per call'), reversibility, absence of a confirmation step, and domain rules (trash_* labels are untouchable, spam/sent/drafts excluded). This is exactly the added context annotations cannot convey.

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?

Front-loaded with the core action, then compact semicolon-separated rules, then an Args block. Dense but every clause carries information; the Args block slightly restates the body but earns its place given the zero-coverage schema.

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 two-parameter batch mutation with an output schema available, the description covers the action, safety profile, batch cap, label vocabulary and explicit exclusions. Nothing an agent needs to call it correctly is missing.

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 carries the burden and largely does: threadId accepts 'a thread ID, or a list of IDs' and labelIds accepts IDs or exact names. The accepted label vocabulary (INBOX/UNREAD/STARRED/IMPORTANT/CATEGORY_*, user label IDs via list_labels) is spelled out, though the empty-list and mixed-ID edge cases are unaddressed.

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?

States a specific verb and resource ('Remove labels from a whole thread') with batch scope made explicit ('or from a list of threads'). The thread-vs-message boundary versus unlabel_message is implied by 'whole thread' rather than named, so it stops short of full sibling differentiation.

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?

Gives concrete when-to-use mappings (Archive = unlabel INBOX; mark read = unlabel UNREAD) and explicit when-not guidance ('spam, sent and drafts: never', trash handled by trash_*). It also states no confirmation is needed and that the operation is reversible, which the agent needs before acting.

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