remove_label

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

With no annotations supplied, the description carries the full burden and does meaningful work: it discloses idempotent behavior ('No error if the label was not present') and documents the exact success payload including the updated labels array. It omits permission/auth requirements and failure modes such as an invalid message_id, which keeps it from a 5.

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 action, then parameter requirements, then return shape, then a workflow note — a sensible order for an agent parsing it. The 'Workflow note' sentence largely restates the opening line, so one sentence is slightly redundant.

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 mutation tool with no output schema and no annotations, the description covers inputs, the success return value, and idempotency — enough to call it correctly. Missing auth/prerequisite context and the absence of any failure-case description are the only gaps.

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 must compensate, and it does: both parameters are listed with types and clarified meaning ('Gmail message ID', 'label name to remove'). It still doesn't say whether the label is a display name or a system label ID, which is the one ambiguity for Gmail-style APIs.

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 opens with a specific verb+resource pair ('Remove a label from an email'), which cleanly separates it from the sibling add_label and from message-level siblings like trash_email or archive_email. It does not explicitly name an alternative tool, so it stops short of a 5.

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?

Usage is implied by the verb and by the workflow note stating the label is removed from the message's label set, but there is no explicit 'use this when...' or reference to add_label / batch alternatives such as add_labels. An agent can infer the use case but gets no routing guidance.

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